essay on life under the sea

WSDF 2020, Mar 5-7 | Durango, Mexico

The Ocean: Life Below Water and Why it Matters

Key questions >>>

• Why does the ocean matter? How is the ocean important for sustainable development?
• What does the sustainable blue economy offer us?
• What are the ocean knowledge gaps?
• How do we need to develop a multidisciplinary ocean science?

The ocean covers around three-quarters of the earth's surface and contains more than 90% of living species on our planet. The ocean is also the single largest ecosystem in the world, and it provides food for billions of people worldwide, as well as maritime transport, renewable energies, and other goods and services like regulating, cultural and supporting services. 

Nevertheless, the ocean is not indestructible, and our footprint is very large. Overfishing, toxic pollution, invasive species, nutrient over-enrichment, habitat degradation and destruction, biodiversity loss, dependence of a growing global population on its goods and services, and coastal development, all threaten the sustainability of coastal ocean ecosystems ( Vanderweerd in Sherman and McGovern, 2011). Ocean acidification is also a growing threat that may be more important than warming, pollution and overfishing (Roberts, 2011).

Why Does the Ocean Matter?

Oceans mean different things for different people: life, passion or wonderment; vastly important; a very important source of life and energy; an incredible source of food and amazing source of biodiversity; it's wild, exciting, terrifying and exhilarating; means a lot to me, if something happens I will not have the fun I’m used to; it's a livelihood, it's been there for generations and hopefully will be there for generations to come.’ (Adapted from video excerpt, Plymouth Marine Laboratory, 2011, in Muñoz-Sevilla and Le Bail 2017).

According to the World Wildlife Fund, the ocean is currently valued at $24 trillion dollars. The goods and services from marine environments add up to an additional $2.5 trillion yearly. This means the ocean would have the seventh-largest GDP in the world.  However, the value of the ocean relies on its current output, which in turn depends on its conditions. Climate change, ocean acidification, habitat destruction, pollution and overfishing are endangering the ocean and threatening its value and the security and livelihood of the three billion people who depend on it. Most of these people live in Small Island Developing States, they are among the ones who contribute least to these issues, but they are the ones at most risk, as they’re already vulnerable. ( Hoegh-Guldberg 2015)

Agenda 2030: SDG 13 and SDG 14

A historical change has been taking place for the past 23 years, from Agenda 21 to Agenda 2030. At the Rio de Janeiro Earth Summit in 1992, more than 178 countries adopted Agenda 21. The Millennium declaration was adopted after the 2000 Millennium Summit in New York. 10 years after the Rio Earth Summit, in the Millennium Development Goals (MDGs) that were adopted during the Earth Summit in Johannesburg, ocean issues were included in the conversation for the first time. 

In 2012, at the United Nations Conference on Sustainable Development (also popularly known as Rio+20), member states adopted the document titled “The Future We Want”, which set the process of developing the sustainable development goals (SDGs) building on the MDGs. Finally, during the UN Sustainable Development Summit in 2015, seventeen SDGs were adopted which are an integral part of the 2030 Agenda.  

Progress of SDG 14 in 2019

The expansion of protected areas for marine biodiversity and existing policies and treaties that encourage responsible use of ocean resources are still insufficient to combat the adverse effects of overfishing, growing ocean acidification and worsening coastal eutrophication. As billions of people depend on oceans for their livelihood and food source, increased efforts and interventions are needed to conserve and sustainably use ocean resources at all levels. 

• Ocean acidification is caused by the uptake of atmospheric CO 2 by the ocean, which changes the chemical composition of the seawater. Long-term observations over the past 30 years have shown an average increase of acidity of 26 percent since pre-industrial times. At this rate, an increase of 100 to 150 percent is predicted by the end of the century, with serious consequences for marine life. 
• To achieve sustainable development of fisheries, fish stocks must be maintained at a biologically sustainable level. Analysis reveals that the fraction of world marine fish stocks that are within biologically sustainable levels declined from 90 percent in 1974 to 66.9 percent in 2015. 
• As of December 2018, over 24 million km 2 (17.2 per cent) of waters under national jurisdiction (0–200 nautical miles from a national border) were covered by protected areas, a significant increase from 12 percent in 2015 and more than double the extent covered in 2010. The protected areas increased from 31.2 per cent in 2000 to 44.7 per cent in 2015 and to 45.7 per cent in 2018. 
• Illegal, unreported and unregulated fishing remains one of the greatest threats to sustainable fisheries, the livelihoods of those who depend upon them and marine ecosystems. Most countries have taken measures to combat such fishing and have adopted an increasing number of fisheries management instruments in the past decade. 
• Small-scale fisheries are present in almost all countries, accounting for more than half of total production on average, in terms of both quantity and value. To promote small-scale fishers’ access to productive resources, services and markets, most countries have developed targeted regulatory and institutional frameworks. However, more than 20 per cent of countries have a low to medium level of implementation of such frameworks, particularly in Oceania and Central and South Asia.

The Ocean Decade

To recognize that more needs to be done to mitigate the global decline in ocean health, in December 2017, the UN declared 2021 to 2030 as the decade of ‘Ocean Science and Sustainable Development’. 

The Ocean Decade will strengthen international cooperation in all levels by strengthening dialogues, developing partnerships, developing capacity-building and leveraging investment, while supporting the entire 2030 Agenda for sustainable development. Other critical goals include improving ocean literacy and education to modify social norms and behaviors, and creating new models for ocean action.

The Ocean Decade aims to include science-informed mitigation and adaptation policies around the world and share knowledge with coastal communities who are most vulnerable to the changes of the ocean. (Claudet et al. 2019)

The COVID-19 Pandemic and the Ocean 

From Little Blue Letter, Glen Wright

• Marine creatures are enjoying some quiet time as underwater noise levels drop. Scientists are studying these effects on marine mammals.
• ​From Florida to Thailand, the number of sea turtles nests has increased on the now-empty beaches. The rapid recovery of marine wildlife in coastal areas shows how extensive our impacts are and highlights the importance of protected areas. 
• Fishers around the world are struggling with decreased demand, lack of sanitary conditions and logistical challenges. In some countries, like India, food security of the communities may be affected by this disruption of supply chains.
• PADI and Rash’R are producing (non-profit)  reusable face masks made from Ocean plastic , with designs based on sea animals!

Final Remarks

We can all take small steps towards protecting our ocean. Reduction of single-use plastic, responsible fish consumption, avoiding ocean harming products, and making your voice heard can all directly contribute towards a healthier ocean. However, more indirect approaches can be taken by reducing the amount of greenhouse gases produced by our daily activities and, therefore, reducing our carbon footprint. Reducing red meat consumption, consuming locally sourced products and using personal vehicles less are all examples of small steps we can take towards reducing our impact. The sum of individual actions can truly make a difference in the fate of our ocean.

Collectively, we need to form a global ocean community, acknowledging that all of our actions have an impact on the ocean (Claudet et al. 2019). And, although it is incumbent on each of us to take steps to protect the ocean, collective action is also required. New models for ocean action, which are collaborative, intergenerational, cross-cultural, and multi-sectoral, are needed in the coming decade, in order to protect our beloved ocean. 

The ocean is our life support system, it connects every one of us, you can think of the ocean as the blue heart  of this planet, but then we look after that heart and we know how we are damaging it and it needs intensive care. We know that scientists, politicians and stakeholders are talking to each other, but it isn’t just up to them, each and every one of us can make the difference, even if the difference might be small, after all individual small drops of sea water can make up the vast ocean . (Adapted from video excerpt, Plymouth Marine Laboratory 2011, in Muñoz-Sevilla and Le Bail 2017).

Bibliography

Cheung, W. et al (2013), “Signature of Ocean Warming in Global Fisheries Catch”, Nature, 497(2013): 365–368.

Claudet, J. et al (2019), “A Roadmap for Using the UN Decade of Ocean Science for Sustainable Development in Support of Science, Policy, and Action”, One Earth , 2(1): 34-42.

Halpern, B. et al (2012), “An Index to Assess the Health and Benefits of the Global Ocean, Nature , 488(2012): 615–620.

UNESCO and UNEP (United Nations Educational, Scientific and Cultural Organization and United Nations Environment Programme) (2016), Large Marine Ecosystems: Status and Trends, Summary for Policy Makers , Nairobi: UNEP.

Muñoz-Sevilla N. and M. Le Bail M (2017), “Latin American and Caribbean Regional Perspectives on Ecosystem Based Management (EBM) of Large Marine Ecosystems Goods and Services”, Environmental Development , 22(2017), 9-17.

Munoz-Sevilla N. et al (2019), UNU Ocean Institute Scoping Study Report , Tokyo: United Nations University.

Plymouth Marine Laboratory (2011), Ocean Acidification: Connecting Science, Industry, Policy and Public (A Short Film for the Natural Environment Research Council and the UK Ocean Acidification Research Programme), Plymouth Marine Laboratory

Roberts D. (2011), In: Ocean Acidification: Connecting Science, Industry, Policy and Public . A short film for the Natural Environment Research Council and the UK Ocean Acidification Research Programme. Plymouth Marine Laboratory.

Sherman, K. and G. McGovern (2011), Toward Recovery and Sustainability of the World’s Large Marine Ecosystems during Climate Change , Gland, Switzerland: International Union for Conservation of Nature.

Sherman K. et al (2017), “Sustainable Development of Latin American and the Caribbean Large Marine Ecosystems”, Environmental Development , 22(2017), 1-8.

United Nations (2015), Transforming Our World: the 2030 Agenda for Sustainable Development , New York: UN.

Wright G. (2020), “The Pandemic and the Ocean”, Email Correspondence on May 1, 2020.

Hoegh-Guldberg, O. (2015), Reviving the Ocean Economy: The Case for Action , Geneva: World Wide Fund for Nature.

Consulted on April 24th, 2020. (2019) What is the United Nations Decade of Ocean Science for Sustainable Development?. https://www.oceandecade.org/about?tab=our-story . Consulted on May 4th, 2020.

.

, .

, , .

, , , , , , .

The Amazing Ocean: The Facts of Life Under the Sea

A well-known chinese proverb maintains that a picture is worth a thousand words. that’s especially true in a world where we’re bombarded with information,..., by dive training.

A well-known Chinese proverb maintains that a picture is worth a thousand words. That’s especially true in a world where we’re bombarded with information, where data is amassed at a rate boggling the minds of those of us who learned math on slide rulers. It seems that anything that can help us “cut to the chase” is not only appreciated, but often the only way we can get a message across. The famous KISS principle — “keep it simple, stupid” — should perhaps be revised to “keep it simple and succinct, stupid” but I suspect there might be a few concerns over the new acronym.

In our quest for brevity, even facts are sometimes too much to process. In order to make a point, we often render knowledge down to its essence, much like boiling a chicken for soup stock. These snippets of knowledge can be very powerful tools for describing the sum and substance of a concept or relating its true state. I was reminded of the power of simplicity as I was preparing to write this article on the plight of the world’s oceans.

As many of you realize (I hope), to bring the troubled state of the aquatic realm to the fore, this year has been designated by the United Nations and others as the International Year of the Ocean. As I researched this story it occurred to me that the best way to make a point might not be to try to bring any focus, elaboration or opinion to bear, but merely let the facts speak for themselves, like a great photograph — the Marines raising the flag on Iwo Jima or the fireman carrying the child out of the rubble of the Oklahoma City bombing. Interpretation can be a needless distraction at times.

What follows is merely a presentation of facts. Taken individually, none probably has much substance. But when viewed in context and in relation to one another, the story they relate is both fascinating and alarming.

Ocean Facts

The oceans contain 99 percent of the living space on Earth, covering over 71 percent of its surface. In all, the oceans contain 328 million cubic miles/1.34 billion cu. km of water.

Ninety-seven percent of the water on Earth is sea water. Less than 1 percent is fresh, while another 2 to 3 percent is contained in glaciers and icecaps.

The surface area of the Pacific Ocean alone exceeds the surface area of all land masses combined.

The record for the longest coastline goes to Canada, with 56,453 miles/ 90,906 km. That’s around 15 percent of the world’s total 372,384 miles/599,652 km of coastline.

Sea water contains almost every element on Earth. In fact, if all the salt were extracted it could cover the continents to a depth of 5 feet/1.5 m. And if all the gold could be extracted, every man, woman and child on Earth would have about 9 pounds/4 kg.

While the average land elevation is 2,755 feet/840 m, the average depth of the ocean is 12,238 feet/3,730 m. The deepest part is the Marianas Trench in an area called Challenger Deep, where it’s 35,802 feet/10,912 m to the bottom, a depth that could completely submerge Mount Everest by more than 8,000 feet/2,438 m. The pressure at the bottom is an astounding 8 tons per square inch. That’s like one person trying to support 50 jumbo jets.

Speaking of Mount Everest, if you thought it was the tallest mountain on Earth, think again. Although Mount Everest is 29,028 feet/8,847 m, when measured from the sea floor, Hawaii’s Mauna Kea is 33,465 feet/10,200 m. (Only 13,796 feet/4,205 m stands above sea level, however.)

On the subject of mountains, the Earth’s longest range is — where else? — underwater. It’s called the Mid-Ocean Ridge and winds its way from the Arctic Ocean through the Atlantic, skirting Africa, Asia and Australia, and crosses the Pacific to the west coast of North America. That’s four times longer than the Andes, Rockies and Himalayas combined.

While land-based volcanic eruptions garner most of the publicity, more than 90 percent of all volcanic activity occurs in the oceans. Scientists have, in fact, located the largest known concentration of volcanoes along the sea floor of the South Pacific in an area roughly the size of New York state. The area contains over 1,100 volcanic cones and seamounts, two or three of which could erupt at any time.

The Atlantic Ocean is still growing at a rate of 1.5 inches/4 cm per year. That means it was about 66 feet/20 m narrower when Columbus landed.

If you think it’s cold where you dive, consider that the average sea-water temperature is a bone-chilling 38˚F/3.5˚C. However, sea surface temperatures in the Persian Gulf can reach over 96˚F/36˚C.

Most of us think of ocean currents as relatively permanent features flowing in only one direction, but there is a notable exception. In the Indian Ocean, currents are seasonal, driven by the monsoon winds. From November to March the current is driven toward Africa, only to reverse direction in May with the changing wind pattern.

The term “Arctic” is derived from the Greek arktos, meaning bear. It was named for the polar bear, Ursus maritimas (sea bear). These creatures are so adapted to life on the ice packs that some never set foot on land.

The largest tidal wave (tsunami) ever recorded was 210 feet/64 m high. It struck Siberia’s Kamchatka Peninsula in 1737.

Life began in the seas sometime between 3.1 and 3.4 billion years ago. But it didn’t move to land until about 400 million years ago, proving that our connection to the sea is far older than to land. Two thirds of the phyla, the major groupings of life on Earth, are exclusively or predominantly found in the ocean.

The base of the marine food chain is the tiny, free-floating organism called phytoplankton, on which almost all other life in the sea is dependent. In fact, as they produce about 50 percent of our oxygen supply, all life on Earth depends on these diminutive wanderers. They are so prolific that each year 200 million tons of phytoplankton grow in the world’s oceans. For comparison, that’s 10 times the weight of the entire human population of our planet.

The blue whale, Balaenoptera musculus, is the largest known animal ever to have lived on sea or land. Bigger than even the biggest dinosaur, it can reach more than 110 feet/33 m in length and weigh more than 50 adult elephants. With a heart the size of a Volkswagen Beetle, the whale’s blood vessels are so large that a full-grown trout could swim through them. To sustain its bulk, the blue whale must consume up to 4 tons of krill per day.

Speaking of big, while most divers know that the largest fish in the sea is the whale shark, less well-known is the largest bony fish. (Shark are cartilaginous, remember.) The winner is the rarely seen ocean sunfish, Mola mola, which can grow to over 10 feet/3 m and tip the scales at over 2 tons.

On the opposite end of the size chart is the dwarf goby, Eviota sp., of the Indian Ocean. As a full-grown adult it reaches a mere .35 inches/9 mm. The record for the smallest shark is the spined pygmy, Squaliolus laticaudus, which measures a whopping 6 inches/15 cm.

If you think finding a date is tough, consider the plight of some deep-sea fishes like the angler fish, Photocorymus hippurus. The male, tiny in comparison to the female, attaches itself by biting his companion. Then the two merge into one, with the male becoming nothing more than a small, permanent appendage that fertilizes eggs.

Many divers are all too familiar with the highly potent sting of the jellyfish — actually a siphonophore — called the Portuguese man-of-war, Physalia physalis. The bluish saclike creature can extend its powerful tentacles to depths of almost 100 feet/30 m. What you may not know is that this critter isn’t a single organism at all. It’s actually a colony of as many as 100,000 tiny individuals, each doing its own specialized job.

Few folks realize that a huge mat of sargassum — a type of marine algae — the size of India floats permanently in the middle of the North Atlantic. It’s held there solely by the circulation pattern of oceanic currents, most notably the Gulf Stream. Aptly, it’s known as the Sargasso Sea.

It wasn’t until 1977 that scientists discovered an entirely new basis for life on Earth — chemosynthesis. Hydrothermal vents which occur at fractures along deep-sea oceanic plates spew sulfur compounds, which support the only complex ecosystem known to run on chemicals rather than energy from the sun. It is now hypothesized by some that this is where life on Earth began.

Stories of sea serpents may be true after all — except that they’re not monsters, but rare fish. Such stories probably originated from sightings of the oarfish, Regalecus glesne, which at 50 feet/15 m long is the longest bony fish in the world.

The structure and chemistry of coral is so close to human bone that coral is now sometimes used to repair or replace bone in humans.

There’s a good reason Atlantic horseshoe crabs, Limulus polyphemus, look like they’re products of the special-effects department of Jurassic Park. They have remained essentially unchanged for the past 135 million years. More importantly to humans, their blood is used to test for the toxins that cause septic shock, a condition which at one time accounted for half of all hospital-acquired infections and one-fifth of all hospital deaths.

Global fish production yields more than cattle, sheep, poultry or eggs and is the biggest source of protein in the world. Yet in an amazing example of Alice-in-Wonderland economics, the worldwide fishing industry spends $124 billion per year to catch only $70 billion worth of fish. This difference is made up by government subsidies.

Fully one-third of the total worldwide catch (27 million metric tons) of commercial marine fisheries is discarded as “by-catch,” most of which dies. This includes not only nontargeted fish, but seabirds, sea turtles and marine mammals as well. The shrimp industry is even worse. Shrimp trawlers discard 80 to 90 percent of their hauls, so for every pound of shrimp you eat, more than 4 pounds/1.8 kg of fish are wastefully tossed overboard to die.

Weighing 1,500 pounds/679 kg and capable of swimming up to 55 miles/89 km per hour, Bluefin tuna, Thunnus thynnus, are among the largest and fastest fishes. Unfortunately, they’re also in high demand at Japan’s sushi bars. One fish can sell for over $25,000, placing an incredible and unsustainable demand on the stock.

Ask most people what’s the No. 1 pollution problem facing the ocean, and you’re likely to hear about oil spills. The fact is that of the 5 million tons of oil that enters the oceans each year, spills from tankers and oil platforms account for only about 5 percent of the total. Twice that amount comes from sewage treatment plants like the one down the street from you. Think of that the next time you change your car’s oil and are tempted to pour the waste down the drain.

As testament to the interrelatedness of the atmosphere and ocean, fully one-third of toxic contaminants and excess nutrients entering the ocean come from atmospheric deposition from rain and snow.

Serving as the drainage basin for almost 40 percent of the continental United States, the Mississippi River carries so many excess nutrients into the Gulf of Mexico that oxygen loss from algal blooms has decimated all life within 4,000 square miles/10,363 sq. km of bottom area off the coast of Louisiana and Texas. Scientists refer to this as the Gulf of Mexico’s “Dead Zone.”

One of the most serious threats to marine ecosystems today comes from hitchhikers. Various organisms, such as the zebra mussel, Dreissena polymorpha, have been transported worldwide in the ballast water of ships. These organisms often disrupt entire marine ecosystems. Not limited to bivalves, exotic stowaways include fishes, plants, poisonous algae and even diseases such as cholera.

If it seems crowded when you go to the beach, consider that one-half of the world’s people live within 60 miles/97 km of the sea coast. And it’s going to get worse. Within 30 years, a billion more people than are alive today (6.5 billion) will be living along the coasts.

In case you think global warming isn’t a serious problem, consider this: An increase of 7˚F/4˚C in the average global atmospheric temperature would melt enough of the polar icecap to increase the sea level some 230 feet/70 m. Virtually every coastal city in existence would be history.

Recently, I read a quote by Arthur C. Clarke, a longtime ocean advocate and author of the classic novel 2001: A Space Odyssey, which succinctly puts the issue of the world’s oceans into perspective. “It seems odd,” he writes, “that we call our home planet Earth when it is clearly Ocean.” How true.

Most of the facts in this article came from two outstanding Web sources. For more information about the oceans and the problems facing them, check out the Web site for the Smithsonian Institution’s Ocean Planet exhibition, Seaweb www.seaweb.org .

Story by Alex Brylske

Jump to a new category...

Related posts.

• The Alien Invasion: Non-native Species Invade the U.S.
• The Glow Below: Bioluminescence in the Sea
• The Underwater Science of Sound
• The Marvel of Moon Jellies: Shapeshifting and Other Survival Strategies for Deep Exploration
• Why Are Reef Fish so Colorful? The Science Behind the Beauty

Goal 14: Life Below Water

SDG14: Life Below Water

Can you imagine a world without oceans to swim in and explore? Oceans are home to seahorses, dolphins, whales, corals, and many other living creatures. Oceans are our planet’s life support as they provide water, food and help regulate the weather. Oceans also provide jobs for more than 3 billion people who depend on marine biodiversity for their livelihood. If we do not stop polluting our oceans, there will be severe problems that affect every person and living creature on the planet.

Pollution poses the greatest threat to our planet and the lives of future generations! Do you ever ask yourself where all the plastic bottles and bags go after you use them? Every year an estimated 5 to 12 million metric tons of plastic enter the ocean. Carbon emissions produced by human activities, like driving cars, are causing the oceans to warm and increase the acid level in the water. This is extremely bad for animals and organisms that live in the sea, as the acid can break the organisms’ shells and damage coral reefs.

All of us need to help to protect our seas. You can suggest to your parents not to use plastic bottles at home, but use a filter instead, if your tap water allows. Next time you go to the beach, bring a reusable bag to collect garbage, so it does not enter the water.

Our new reading list for SDG14: Life Below Water explains the importance of the ocean and the resources it provides to all of us, teaching you what you can do to keep our seas clean. The books will take you on underwater journeys and introduce you to many unique sea creatures while helping to understand what problems affect ocean’s health.

Table of Contents

Sign up for updates

SDG Book Club Chapters

More recommendations

On the importance of reading

Reading list

The Big Book of the Blue

The Big Book of the Blue explores the underwater world through several themes such as looking at animals in danger, learning how to spot creatures at the beach, and discovering how to do our part to save sea life. Filled with fascinating facts, this book’svivid illustrations bring to life some of the most interesting underwater animals.

Author and Illustrator: Yuval Zommer | ISBN: 9780500651193 | Publisher: Thames & Hudson

Heads and Tails: Underwater

This book encourages children’s imagination and curiosity, as the illustrations let them guess what creatures live in the world’s waters. It’s a great conversation starter about how pollution endangers these animals and what each child can do to help protect life under water and keep our oceans, lakes, and rivers clean.

Author and Illustrator: John Canty | ISBN: 9781536214604 | Publisher: Candlewick

Water: A Deep Dive of Discovery

This comprehensive yet accessible exploration of water will help young readers understand many aspects of one of our planet’s most precious resources – and how they can protect it. A friendly water droplet character guides children through topics ranging from melting and freezing to the ways in which water literally shapes the Earth.

Author: Christy Mihaly |  Illustrator: Mariona Cabassa | ISBN: 9781646862801 | Publisher:  Barefoot Books

Shark Lady: The True Story of How Eugenie Clark Became the Ocean’s Most Fearless Scientist

A story about Eugenie Clark who fell in love with sharks from the first moment she saw them at the aquarium and couldn’t imagine anything more exciting than studying these graceful creatures. Through her accomplishments, she taught the world that sharks were to be admired rather than feared and that women can do anything they set their minds to.

Author: Jess Keating |  Illustrator: Marta Álvarez Miguéns  | ISBN: 9781492642046 | Publisher:  Sourcebooks Explore

If You Want to Visit a Sea Garden

Sea gardens have been created by First Peoples on the Northwest Coast of North America for more than three thousand years. These gardens consist of stone reefs that are constructed at the lowest tide line, encouraging the growth of clams and other marine life on the gently sloped beach. This story follows a young child and an older family member who set out to visit a sea garden early one morning, as the lowest tides often occur at dawn.

Author: Kay Weisman |  Illustrator: Roy Henry Vickers  | ISBN: 9781554989706 | Publisher:  Groundwood Books

Reading is a great way to better understand what people from across the globe struggle with in their everyday lives, and it helps us reflect on our own situation. But reading is just the first step: now it’s time to share your book club experiences and how you plan to take action. Each month, we will feature a couple of book clubs on our blog , so get ready to share your story through social media, by using #SDGBookClub and tagging @UNPublications.

We know it can be difficult to stay at home to protect ourselves and our loved ones from COVID-19. This is why we created a new guide on how to organize your own SDG Book Club online to connect with your friends and family while sharing the joy of reading. We look forward to hearing about your experience on social media using #SDGBookClub.

Help us spread the word by downloading our promotional materials. You will find a horizontal banner, bookmark, placard and easy-to-print sign-up sheet for your friends, family and community to join the SDG Book Club!

Frequently Asked Questions

What is the sdg book club.

The SDG Book Club aims to use books as a tool to encourage children ages 6-12 to interact with the principles of the Sustainable Development Goals (SDGs) through a curated reading list ofbooks from around the world related to each of the 17 SDGs in all six official UN languages—Arabic, Chinese, English, French, Russian, and Spanish.

How do you choose books for the reading list?

A selection committee works together to make the final selection for each of the 17 SDGs, in all six official UN languages —Arabic, Chinese, English, French, Russian, and Spanish. The selection committee consists of members from the United Nations, International Publishers Association (IPA), the International Federation of Librarian Associations (IFLA), European and International Booksellers Federation (EIBA), International Authors Forum (IAF), and International Board on Books for Young People (IBBY).

What sorts of books will be considered for this reading list?

Fiction, non-fiction, and other genres that our panel thinks will help educate children about SDGs will be considered.

What is the target age for the reading list?

The reading list is meant for children ages 6-12. However, we encourage parents, educators, and everyone who is interested to read the selected books and help children understand the importance of the SDGs.

How often is the reading list updated?

The reading list will be published during the first week of every month for 17 months, starting with Goal 1: No Poverty in April 2019 and culminating with Goal 17: Partnerships for the Goals in September 2020 for the 5th anniversary of the SDGs.

Can I sign-up for email updates?

Yes. Sign up on our homepage to get a monthly email on news and updates. Your privacy is important to us so we would never share your information with third parties or spam your inbox.

Do you sell books here?

No. We do not intend to sell or promote the sale of the books featured in the reading list. If you chose to, you can buy the books online, wherever books are sold, or get a copy at your local bookstore or library.

How do I participate in the conversation via social media?

You can post your thoughts and images on social media using the hashtag #SDGBookClub . Please tag/follow us on Twitter  and Facebook.

Is there a book club meeting near me which I can join?

Yes, there are book club meetings taking place all over the world. Check back for a link to the list! (Coming soon)

How can host my own book club meeting and add it to the list of events?

People can host book club meetings around the world and share their photos via #SDGBookClub. If you would like to organize a public book club meeting, we recommend contacting your local book store, library or school and set it up with them. Please share the planned event on social media using #SDGBookClub and we will add it to the list of events.

I have some thoughts. How do I send feedback?

You can post feedback on our Facebook page or write an email to: [email protected] .

Can I make recommendations for the reading list?

We sincerely appreciate your interest. However, we are not currently accepting recommendations.

What other actions can I take to promote the SDGs?

There are actions that you can take beyond just reading the books.

A/ Help your kids to create a poster with a photo or drawing and interesting facts about their favourite character(s) of the book.

B/ Design a reading scavenger hunt for kids using drawings and pictures instead of questions and help them search for things mentioned in the book.

C/ Help your kids write a letter to the local government representative and tell them what you learned in the book and ask them what action(s) they are taking toward a specific Goal.

D/ Organize a parent-child facilitated book discussion for younger kids. Invite your child’s friends and their parents to discuss a book from the reading list at your local library or children’s book store.

E/ Spread the word on social media, using the hashtag #SDGBookClub. We’d love to feature your pictures/videos on our social media.

What else can I do to teach children about the SDGs?

You can find plenty of Student Resources here . You will find other books aimed at children, as well as the SDG board game. The game aims to help teach children around the world about the Sustainable Development Goals in a child-friendly and straightforward way.

Read to a Child campaign : A global campaign on reading to children to encourage literacy and global citizenship, incorporating the priorities youth and quality education. It is planned to take place in September 2020. More information to come. Please sign up to stay informed.

The International Publishers Association (IPA)  is a federation of publishing associations from around the world. The main mandate of the IPA is to promote and defend copyright, support the freedom to publish, promote literacy and reading. IPA is an accredited NGO in consultative status with the Economic and Social Council of the UN. IPA supports the SDGs and works particularly closely with WIPO and UNESCO.

The International Federation of Library Associations and Institutions (IFLA) is the leading international body representing the interests of library and information services and their users. It is the global voice of the library and information profession. Founded in 1927 in Edinburgh, Scotland at an international conference, we celebrated our 90th birthday in 2017. We now have more than 1,300 Members in nearly 150 countries around the world. IFLA was registered in the Netherlands in 1971.

The International Board on Books for Young People (IBBY)  is a non-profit organization that represents an international network of people from all over the  world who are committed to bringing books and children together. Today IBBY comprises 79 National Sections worldwide.

The European & International Booksellers Federation (EIBF)  represents national booksellers associations in the European Union and beyond. EIBF Members in turn have in membership booksellers of all kinds: brick and mortar bookshops, online bookshops, independents, chains.

The Bologna Children’s Book Fair (BCBF)  is the most important international trade fair of the children’s publishing industry. With over 50 years of experience, BCBF has succeeded in bringing together a unique and diverse global audience: the result is the world’s premium copyright business hub when it comes to publishing with an extra core that extends to all multi-media content for children.

SDG Book Club Chapters Around the World

Our SDG Book Club is expanding and we are excited to see SDG reading lists for children from around the world. In addition to the SDG Book Club in the UN’s six official languages (Arabic, Chinese, English, French, Russian and Spanish) there are now chapters in other languages. Visit the SDG Book Club Chapters listed below.

Introductory essay

Written by the educators who created The Deep Ocean, a brief look at the key facts, tough questions and big ideas in their field. Begin this TED Study with a fascinating read that gives context and clarity to the material.

How inappropriate to call this planet Earth when it is quite clearly Ocean. Arthur C. Clarke

Planet Ocean

In the late 1960s, the Apollo Mission captured images of Earth from space for the very first time. These iconic photos gave people around the world a fresh perspective on our home planet — more specifically, its vast and dazzling expanses of blue. It's perhaps unsurprising that science has subsequently established the key roles that the ocean and its marine organisms play in maintaining a planetary environment suitable for life.

While the Apollo astronauts were sending back pictures of our blue planet, a scientist at the Jet Propulsion Laboratory in California was searching for ways to detect life on other planets such as Mars. James Lovelock's investigations led him to conclude that the only way to explain the atmospheric composition of Earth was that life was manipulating it on a daily basis. In various publications, including his seminal 1979 book Gaia: A New Look at Life on Earth , Lovelock launched the Gaia hypothesis, which describes how the physical and living components of the natural environment, including humankind, interact to maintain conditions on Earth. During the same period, marine scientists including Lawrence Pomeroy, Farooq Azam and Hugh Ducklow were establishing a firm link between the major biogeochemical cycles in the oceans and marine food webs, particularly their microbial components. In the late 1980s and 1990s, large-scale research programs like the Joint Global Ocean Flux Study (JGOFS) explored ocean biogeochemistry and established the oceans' pivotal role in the Earth's carbon cycle.

Research efforts like these underscored the oceans' critical importance in regulating all the major nutrient cycles on Earth. It's now widely recognized that the ocean regulates the temperature of Earth, controls its weather, provides us with oxygen, food and building materials, and even recycles our waste.

The advent of deep-sea science

It seems remarkable that until fairly recently many scientists believed that life was absent in the deep sea. Dredging in the Aegean Sea in the 1840s, marine biologist Edward Forbes found that the abundance of animals declined precipitously with depth. By extrapolation he concluded that the ocean would be azoic (devoid of animal life) below 300 fathoms (~550m depth). Despite evidence to the contrary, scientists supported the azoic hypothesis, reasoning that conditions were so hostile in the deep ocean that life simply could not survive. Extreme pressure, the absence of light and the lack of food were viewed as forming an impenetrable barrier to the survival of deep-sea marine species.

But others were already proving this hypothesis wrong. As Edward Forbes published his results from the Aegean, Captain James Clark Ross and the famous naturalist John Dalton Hooker were exploring the Antarctic in the Royal Navy vessels HMS Terror and HMS Erebus . During this expedition, Ross and Hooker retrieved organisms from sounding leads at depths of up to 1.8km, including urchin spines and other fragments of various marine invertebrates, a number of bryozoans and corals. Ross remarked, "I have no doubt that from however great a depth we may be enabled to bring up the mud and stones of the bed of the ocean we shall find them teeming with animal life." This contention was supported by work of Norwegian marine biologists Michael Sars and George Ossian Sars who dredged hundreds of species from depths of 200 to 300 fathoms off the Norwegian coast.

Further evidence came from natural scientists William Carpenter and Charles Wyville-Thomson, who mounted expeditions in 1868 and 1869 on the vessels HMS Lightening and HMS Porcupine to sample the deep ocean off the British Isles, Spain and the Mediterranean. The findings of these expeditions, which Wyville-Thomson published in his 1873 book The Depths of the Sea , confirmed the existence of animal life to depths of 650 fathoms — including all the marine invertebrate groups — and suggested that oceanic circulation exists in the deep sea.

This convinced the Royal Society of London and the Royal Navy to organize the circumnavigating voyage of HMS Challenger in the 1870s. In part, the expedition's purpose was to survey potential routes for submarine telegraph cables, and so the links between scientific exploration and human use of the deep sea were established in the very early days of oceanography. The Challenger expedition was a watershed for deep-ocean science, establishing the basic patterns of distribution of deep-sea animals, and that their main food source was the rain of organic material from surface waters.

In the 1950s, the Danish Expedition Foundation's Galathea voyage established that life occurred at depths of more than 10km in the Philippines Trench. In 1960 marine explorers Auguste Picard and Don Walsh reached the bottom of the Challenger Deep in the Marianas Trench, at a depth estimated to be 10,916 meters--the deepest part of the ocean — where they observed flatfish from the porthole of their pressure sphere. This feat was not repeated until 2012 when James Cameron visited the bottom of the Challenger Deep in the submersible Deepsea Challenger .

Hype or hyper-diversity in the deep sea?

While working at Woods Hole Oceanographic Institution in the late 1960s, scientists Howard Sanders and Robert Hessler developed new types of deep-sea trawls called epibenthic sleds that featured extra- fine mesh in the nets. When the new trawls were tested, they recovered an astonishing diversity of species from the deep sea. It became apparent that the species richness of deep-sea communities actually increased with greater depth to a peak somewhere on the continental slope between 2,000 and 4,000 meters depth. Beyond these depths, diversity appeared to decrease (but not everywhere), or the pattern was unclear.

How to explain this amazing diversity in the deep sea? Initially, scientists credited the species richness to the stability of environmental conditions in the deep ocean, which would support extreme specialization of the animals and thus allow many species to coexist. This is known as the stability-time hypothesis. Some scientists considered that small-scale variations of the sediments of the deep ocean, including reworking of seabed by animals, was important in maintaining microhabitats for many species. In the late 1970s other scientists suggested that conditions in shallow waters allow competitive exclusion, where relatively few species dominate the ecosystem, whereas in deeper waters environmental factors associated with depth and a reduced food supply promote biological communities with more diversity.

Fred Grassle and Nancy Maciolek added substantially to our knowledge of deep-sea biodiversity when they published a study of the continental slope of the eastern coast of the USA in the early 1990s. Grassle and Maciolek based their study on quantitative samples of deep-sea sediments taken with box cores. These contraptions retrieve a neat cube-shaped chunk of the seabed and bring it to the surface enclosed in a steel box. Scientists then sieve the mud and count and identify the tiny animals living in the sediment.

In a heroic effort, Grassle and Maciolek analyzed 233 box cores, an equivalent of 21 square meters of the seabed, identifying 90,677 specimens and 798 species. They estimated that they found approximately 100 species per 100 km along the seabed they sampled. Extrapolations of this figure suggested that there may be 1 - 10 million macrofaunal species in the deep sea.

What's more, some scientists argued that Grassle and Maciolek's estimates represented only a small part of the species diversity in the ocean depths. Dr John Lambshead of London's Natural History Museum pointed out that Grassle and Maciolek had not examined the smallest animals in sediments — the meiofauna — made up of tiny nematode worms, copepods and other animals. These are at least an order of magnitude more diverse than the macrofauna, suggesting that as many as 100 million species may inhabit the deep ocean.

However, given that the latest approximation of the Earth's biodiversity is 10 million species in total, Lambshead's number appears to be an overestimate. Scientists have since realized that there are major problems with estimating the species richness of large areas of the deep sea based on local samples. Today we understand that species diversity in the deep ocean is high, but we still don't know how many species live in the sediments of the continental slope and abyssal plains. We also don't understand the patterns of their horizontal distribution or the reasons for the parabolic pattern of species diversity as it relates to depth. Evidence suggests, however, that the functioning of deep-sea ecosystems depends on a high diversity of animals — although exactly why remains open to conjecture.

The creation of deep-sea environments: "Drifters" and "Fixists"

In 1912, German scientist Alfred Wegener put forward his theory of continental drift to address many questions that engaged the geologists and biologists of his time. For example, why do the continents appear to fit together as though they had once been joined? Why are many of the large mountain ranges coastal? And, perhaps most intriguing, why do the rocks and fossil biotas (combined plant and animal life) on disconnected land masses appear to be so similar?

Wegener's theory provoked a major scientific controversy that raged for more than 50 years between "drifters" and "fixists." Critics of Wegener's — the "fixists" — pointed out that Wegener's proposed mechanism for drift was flawed.

In the search for an alternate mechanism to explain continental drift, British geologist Arthur Holmes suggested that radioactive elements in the Earth were generating heat and causing convection currents that made the Earth's mantle fluid. Holmes argued that the mantle would then rise up under the continents and split them apart, generating ocean basins and carrying the landmasses along on the horizontally-moving currents.

Following World War II, scientific expeditions employing deep-sea cameras, continuously recording echo-sounders, deep-seismic profilers and magnetometers lent support to the arguments of Holmes and his fellow "drifters." Scientists realized that the deep sea hosted a vast network of mid-ocean ridges located roughly in the center of the ocean basins. These ridges were characterized by fresh pillow lavas, sparse sediment cover, intense seismic activity and anomalously high heat flow. Scientists found geologically-synchronous magnetic reversals in the rocks of the ocean crust moving away from either side of the mid-ocean ridges. Added to this was the fact that nowhere could scientists find sediments older than the Cretaceous in age. Together, these findings suggested that new oceanic crust was being formed along the mid-ocean ridges, while old oceanic plates are forced underneath continental plates and destroyed along the ocean trenches. By the late 1960s, the bitter scientific debate between the "fixists" and the "drifters" was finally settled.

Life without the sun

During the next decade, scientists investigating volcanic activity at mid-ocean ridges became interested in the associated phenomenon of hot springs in the deep sea. Anomalously high temperature readings over mid-ocean ridge axes led scientists to mount an expedition in 1977 to the 2.5 km-deep Galápagos Rift. From the submersible Alvin, the scientists observed plumes of warm water rising from within the pillow lavas on the seabed. Living amongst the pillows were dense communities of large vesicoyid clams, mussels, limpets and giant vestimentiferan tube worms (Siboglinidae). An abundance of bacteria around the Galápagos Rift site immediately suggested that these communities might be based on bacterial chemosynthesis, or chemolithotrophy, using chemical energy obtained by oxidizing hydrogen sulphide to drive carbon fixation. Subsequent investigation confirmed that the giant tube worms, clams and mussels actually hosted symbiotic sulphur-oxidizing bacteria in their tissues.

The discovery caused huge excitement in the scientific community. Here was life thriving in the deep sea, where primary production — the basis of the food web — was independent from the sun's energy. Furthermore, as scientists discovered additional vent communities and surveyed elsewhere in the mid-ocean ridge system, they found that environmental conditions were extreme, with high temperatures, acidic waters, hypoxia (lack of oxygen) and the presence of toxic chemicals the norm.

The implications of this were enormous and went well beyond the study of the ocean itself. First, it meant that life could exist elsewhere in our solar system in environments previously thought too extreme. Second, it widened the potential area for habitable planets around suns elsewhere in the universe. For example, the discovery in 2000 of the Lost City alkaline hydrothermal vents presented an environment that some scientists suggest is analogous to the conditions in which life evolved on Earth.

Subsequently, chemosynthesis has been discovered in many places in the ocean, including deep-sea hydrocarbon seeps, in large falls of organic matter such as whale carcasses, and from shallow-water sediments associated with, for example, seagrass beds.

Drawing down the oceans' natural capital

Over the past two decades, we've developed a much deeper understanding of the relationship between humankind and the natural world, including the Earth's oceans. In 1997 Robert Costanza and his colleagues published a paper in Nature that estimated the economic value of the goods and services provided by global ecosystems. Costanza and his colleagues argued that the living resources of Earth could be viewed as a form of natural capital with a value averaging $33 trillion per annum, upon which the entire human economy depended. These goods and services were later grouped into supporting (e.g. primary production), provisioning (e.g. food), regulating (climate regulation) and cultural (e.g. education) services.

While this knowledge may have been intuitive for many people, Costanza's recasting of the environment in economic terms forced policymakers, industry leaders and others to recognize the importance of long-term environmental sustainability. With the support of international agencies such as the World Bank, many countries are now implementing natural capital accounting procedures through legislation. The purpose of this is to help monitor and regulate the use and degradation of the environment and to ensure that the critical ecosystem goods and services underpinning economic activity and human well-being are not undermined.

Although it seems like a modern preoccupation, sustainability is actually a centuries-old challenge, particularly as it relates to marine environments. For example, there is evidence that aboriginal fisheries in ancient times may have overexploited marine species. Certainly by medieval times in Europe, a thriving market for fish, coupled with other developments like changing agricultural practices, forced species such as salmon and sturgeon into decline.

The Industrial Revolution led to an increase in hunting fish, seals and whales, thanks to the development of steam- and then oil-powered fishing vessels that employed increasingly sophisticated means of catching animals. Pelagic whaling began in the early 20th century; the development of explosive harpoons, the ability to process whales at sea, and the strong demand for margarine made from whale oil all contributed to dramatic rises in catches. Despite the initiation of the International Whaling Commission in 1946, a serial depletion of whale populations took place from the largest, most valuable species (e.g. blue whale) through to the smallest species (minke whale). The failure to regulate catches of whales led to the establishment of a near-moratorium on whaling in 1986.

Over the same post-war period, fishing fleets underwent a major expansion and deployed increasingly powerful fishing vessels. Improved technologies for navigating, finding fish and catching them led to increasing pressure on fish stocks and the marine ecosystems in which they lived. In 1998, after analyzing catch statistics from the United Nations Food and Agricultural Organisation (FAO), Daniel Pauly and his colleagues from the University of British Columbia identified a global shift in fish catches from long-lived, high trophic level predators to short-lived, low trophic level invertebrates and plankton-eating fish. This was the first evidence that fishing was having a global impact on marine ecosystems, causing major changes in the structure of ocean food webs. Aside from the economic impacts of "fishing down the food web," evidence was accumulating that it also affected the vulnerability and/or resilience of marine ecosystems to shocks such as invasions by alien species and climate-change effects such as mass coral bleaching.

Further evidence came in 2003 from a study by Ransom Myers and Boris Worm. Myers and Worm documented a significant decline over time in the stocks of certain large, predatory fish after analyzing information from research trawl surveys and the catches of the Japanese long-line fleet. Other studies over the same time period suggested that sharks, seabirds and turtles were suffering large-scale declines as they became by-catch in many industrial fisheries. Scientists also asserted that some fishing technologies, such as bottom trawling, were extremely damaging to seabed communities — deep-sea ecosystems in particular — by documenting the devastation of cold-water coral communities.

These studies sparked a bitter war of words between marine ecologists, fishing industry executives and fisheries biologists. While it has now been demonstrated that fish stocks can recover if levels of exploitation by fisheries are reduced through management measures, it's clear that in many parts of the world's oceans this is not happening. Overall, global yields from marine capture fisheries are in a downward trajectory. By-catch of some marine predators, such as albatrosses, still poses a threat of extinction. Habitat destruction resulting from fishing is continuing.

In addition to overfishing, other human activities are damaging marine ecosystems. During the 1960s and 1970s, several major accidents with oil tankers and oil installations resulted in serious oil spills. While oil pollution is still a significant problem, as illustrated by the Deepwater Horizon disaster in the Gulf of Mexico in 2010, other less-visible sources of pollution are causing large-scale degradation of the ocean.

Persistent organic pollutants and heavy metals such as mercury are being recognized as major health issues for marine animals (especially high trophic level predators, such as killer whales and tuna) and also for humans. The oceans are becoming the dumping ground for a wide range of chemicals from our personal care products and pharmaceuticals, as well as those that leach out of all manner of plastics that are floating in our seas. Agrochemicals are pouring into the oceans through rivers; in some cases these artificially fertilize coastal waters, generating blooms of algae which are broken down by bacteria, thus stripping the water of oxygen and creating dead zones.

Our release of greenhouse gases into the atmosphere, particularly carbon dioxide (CO2), is leading to a profound disturbance in ocean temperatures and ocean chemistry. Since the late 1970s, mass coral bleaching from ocean warming has killed large areas of tropical coral reefs. Marine animals are changing their distribution and the timing of their lifecycles, sometimes with catastrophic effects across the wider ecosystem. Such effects are often propagated from lower levels of food webs up through to predators such as fish and seabirds: witness recent declines in spectacled sea duck populations in the Arctic and the decline of cod populations in the North Sea. The oceans are becoming more acidic, which affects the growth rates of animals with calcium carbonate shells or skeletons and has other negative impacts on animal physiology. Many of these different stresses on marine species interact in a form of "negative synergy", inducing more severe effects than if they had presented in isolation. At the ecosystem level these stresses reduce the resilience of marine ecosystems to "shocks" arising from large-scale effects, such as anomalous warming events associated with climate change.

Ocean future

The TEDTalks in The Deep Ocean illuminate many current topics in marine science and oceanic exploration. These include the call for better conservation management in the face of unprecedented threats to marine ecosystems, the discovery and application of as-yet-untapped natural resources from the ocean depths, and the quest for improved technologies to support both of these endeavors. As Sylvia Earle eloquently reminds us in her 2009 TEDTalk, the oceans are critically important to maintaining the planet in a condition that is habitable, and better cooperative, international management of marine ecosystems is essential. However, as other TED speakers like Robert Ballard and Craig Venter argue, the oceans should also interest us because they contain vast untapped resources: unexploited mineral resources as well as genes, proteins and other biomolecules of marine life, which may furnish the medicines and industrial materials of the future.

Smart management of these natural resources requires knowledge, as do our efforts to ensure the oceans' ongoing species richness and their critical function in maintaining the Earth system. In their TEDTalks, explorers and scientists Edith Widder, Mike deGruy and Craig Venter share some of the amazing physical and biological features of ocean habitats and describe how new technologies allow more careful study and exploitation of deep-sea environments.

Despite these advances, there are still enormous gaps in our knowledge. In a TEDTalk he gave in 2008, Robert Ballard noted that many parts of the ocean remain entirely unexplored and he advocated for increased resources for organizations like NOAA. As many of the TED speakers in The Deep Ocean argue, marine science is more important than ever because the oceans are under serious threat from a range of human impacts including global-scale climate change.

However, these speakers also offer a message of hope, underscoring that there is still time to alter the current trajectory of degradation. Scientists including TED speaker John Delaney present a vision for the future where ecosystem-based management, coupled with the advent of new technologies that allow us to monitor ocean health in real time, provide us with tools to heal marine ecosystems. This may allow us to restore their capacity to provide goods and services for humankind over the long term. Measures such as marine-protected areas can maintain the oceans' important biogeochemical functions, but will also conserve the remarkable and beautiful marine ecosystems that have culturally enriched the human experience for millennia.

We'll begin our journey into The Deep Ocean with legendary explorer and oceanographer Sylvia Earle, who shares disturbing data about the decline of marine ecosystems and proposes one method to protect what she calls "the blue heart of the planet."

Sylvia Earle

My wish: protect our oceans, relevant talks.

Craig Venter

On the verge of creating synthetic life.

David Gallo

Underwater astonishments.

Edith Widder

Glowing life in an underwater world.

John Delaney

Wiring an interactive ocean.

Mike deGruy

Hooked by an octopus.

Robert Ballard

The astonishing hidden world of the deep ocean.

Life Below Water

The world’s oceans – their temperature, chemistry, currents and life – drive global systems that make the Earth habitable for humankind. Our rainwater, drinking water, weather, climate, coastlines, much of our food, and even the oxygen in the air we breathe, are all ultimately provided and regulated by the sea. Throughout history, oceans and seas have been vital conduits for trade and transportation.

Careful management of this essential global resource is a key feature of a sustainable future. However, at the current time, there is a continuous deterioration of coastal waters owing to pollution and ocean acidification is having an adversarial effect on the functioning of ecosystems and biodiversity. This is also negatively impacting small scale fisheries.

Marine protected areas need to be effectively managed and well-resourced and regulations need to be put in place to reduce overfishing, marine pollution and ocean acidification.

Take the course

One Planet, One Ocean

Governance for Transboundary Freshwater Security

Nature-based Solutions for Disaster and Climate Resilience

Ecosystem-based Adaptation: Working with nature to adapt to a changing climate

One Health in Practice: Solutions for Healthy People in Biosphere Reserves

How to Achieve the SDGs

The Age of Sustainable Development

Transforming Our World: Achieving the SDGs

Measuring Sustainable Development

Changing Behaviour for Sustainable Development

Learn about the other goals.

See individual course listings and start learning today!

or sign in with email

If you received an invite email, sign in with the same email and password you set.

Didn’t receive confirmation email?

• News, Stories & Speeches
• Get Involved
• Structure and leadership
• Committee of Permanent Representatives
• UN Environment Assembly
• Funding and partnerships
• Policies and strategies
• Evaluation Office
• Secretariats and Conventions
• Asia and the Pacific
• Latin America and the Caribbean
• New York Office
• North America
• Climate action
• Nature action
• Chemicals and pollution action
• Digital Transformations
• Disasters and conflicts
• Environment under review
• Environmental law and governance
• Extractives
• Fresh Water
• Green economy
• Ocean, seas and coasts
• Resource efficiency
• Sustainable Development Goals
• Youth, education and environment
• Publications & data

GOAL 14: Life below water

Learn more about SDG 14

Conserve and sustainably use the oceans, seas and marine resources for sustainable development:

The oceans cover more than 70 per cent of the surface of our planet and play a key role in supporting life on earth. They are the most diverse and important ecosystem, contributing to global and regional elemental cycling, and regulating the climate. The ocean provides natural resources including food, materials, substances, and energy. Marine Protected Areas contribute to poverty reduction by increasing fish catches and income, creating new jobs, improving health, and empowering women. Increasing levels of debris in the world’s seas and oceans is having a major and growing economic impact.

Oceans, seas and other marine resources are essential to human well-being and social and economic development worldwide. Their conservation and sustainable use are central to achieving the 2030 Agenda, especially for small island developing States. Marine resources are particularly important for people living in coastal communities, who represented 37 per cent of the world's population in 2010. Oceans provide livelihoods, subsistence and benefits from fisheries, tourism and other sectors. They also help regulate the global ecosystem by absorbing heat and carbon dioxide (CO2) from the atmosphere. However, oceans and coastal areas are extremely vulnerable to environmental degradation, overfishing, climate change and pollution.

UNEP is working to develop a coherent approach to measuring the ocean condition and the drivers, pressures, impacts and responses. This is through promoting the measurement of the ocean SDGs where UNEP is the custodian and through working to develop an approach for better ocean accounts.

UNEP published a Global Manual on SDG 14.1.1, 14.2.1 and 14.5.1 . This manual also provides details related to how the SDGs align with the Regional Seas.

Indicators:

• 14.1.1(a) Index of coastal eutrophication; and (b) plastic debris density (Tier II)
• 14.2.1 Number of countries using ecosystem-based approaches to managing marine areas (Tier II)
• 14.5.1 Coverage of protected areas in relation to marine areas (Tier I)
• International Nitrogen Management System (INMS)
• GEO Blue Planet
• National Oceanic and Atmospheric Administration  (NOAA)
• Commonwealth Scientific and Industrial Research Organisation (CSIRO)
• Institute of Electrical and Electronics Engineers (IEEE)
• Regional Seas
• World Conservation Monitoring Centre(UNEP-WCMC)
• International Union for Conservation of Nature(IUCN)

To learn more about UN Environment Programme's contributions to SDG 14:

• SDG Policy Brief on  Oceans: Marine Pollution
• SDG Policy Brief on  Global Biodiversity Loss

Related Sustainable Development Goals

© 2024 UNEP Terms of Use Privacy   Report Project Concern Report Scam Contact Us

An official website of the United States government

Here’s how you know

Official websites use .gov A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS A lock ( Lock A locked padlock ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

• Education home
• About NOAA Education
• NOAA in your backyard: Alaska
• NOAA in your backyard: Caribbean
• NOAA in your backyard: Central
• NOAA in your backyard: Great Lakes
• NOAA in your backyard: Gulf of Mexico
• NOAA in your backyard: Mid-Atlantic
• NOAA in your backyard: Northeast
• NOAA in your backyard: Northwest
• NOAA in your backyard: Pacific Islands
• NOAA in your backyard: Southeast
• NOAA in your backyard: Southwest
• Educational mailing lists
• Jan-Mar 2024
• Oct-Dec 2023
• Jul-Sep 2023
• Apr-Jun 2023
• NOAA Sea to Sky: Education resource database
• Ocean acidification
• Ocean currents
• Ocean floor features
• Ocean pollution and marine debris
• El Niño and La Niña
• Space weather
• Weather observations
• Weather systems & patterns
• Carbon cycle
• Changing seasons
• Climate change impacts
• Climate data monitoring
• Aquatic food webs
• Coral reef ecosystems
• Fisheries and seafood
• Life in an estuary
• Marine mammals
• Sea turtles
• Great Lakes ecoregion
• Water cycle
• Watersheds, flooding, and pollution
• Data resources for educators
• Education at home
• Elementary resources
• Hands-on science activities
• Special topics
• Conference resources
• About the education resource collections
• Conservation Service Corp Act Direct Hiring Authority
• Finding a career at NOAA
• Educator opportunities
• Grants & networks
• News and stories

Marine life

Our ocean, coasts, and estuaries are home to diverse living things. These organisms take many forms, from the tiniest single-celled plankton to the largest animal on Earth, the blue whale. Understanding the life cycles, habits, habitats, and inter-relationships of marine life contributes to our understanding of the planet as a whole. Human influences and reliance on these species, as well as changing environmental conditions, will determine the future health of these marine inhabitants. Toxic spills , oxygen-depleted dead zones, marine debris , increasing ocean temperatures, overfishing, and shoreline development are daily threats to marine life. Part of NOAA's mission is to help protect these organisms and their habitats.

Food webs describe who eats whom in an ecological community. Made of interconnected food chains, food webs help us understand how changes to ecosystems — say, removing a top predator or adding nutrients — affect many different species, both directly and indirectly.

Phytoplankton and algae form the bases of aquatic food webs. They are eaten by primary consumers like zooplankton, small fish, and crustaceans. Primary consumers are in turn eaten by fish, small sharks, corals, and baleen whales. Top ocean predators include large sharks, billfish, dolphins, toothed whales, and large seals. Humans consume aquatic life from every section of this food web.

Coral reefs are some of the most diverse ecosystems in the world. Coral polyps , the animals primarily responsible for building reefs, can take many forms: large reef building colonies, graceful flowing fans, and even small, solitary organisms. Thousands of species of corals have been discovered; some live in warm, shallow, tropical seas and others in the cold, dark depths of the ocean.

Seafood plays an essential role in feeding the world’s growing population. Healthy fish populations lead to healthy oceans and it's our responsibility to be a part of the solution. The resilience of our marine ecosystems and coastal communities depend on sustainable fisheries.

Estuaries are areas of water and shoreline where rivers meet the ocean or another large body of water, such as one of the Great Lakes. Organisms that live in estuaries must be adapted to these dynamic environments, where there are variations in water chemistry including salinity, as well as physical changes like the rise and fall of tides. Despite these challenges, estuaries are also very productive ecosystems. They receive nutrients from both bodies of water and can support a variety of life. Because of their access to food, water, and shipping routes, people often live near estuaries and can impact the health of the ecosystem.

Marine mammals are found in marine ecosystems around the globe. They are a diverse group of mammals with unique physical adaptations that allow them to thrive in the marine environment with extreme temperatures, depths, pressure, and darkness. Marine mammals are classified into four different taxonomic groups: cetaceans (whales, dolphins, and porpoises), pinnipeds (seals, sea lions, and walruses), sirenians (manatees and dugongs), and marine fissipeds (polar bears and sea otters).

Sea turtles breathe air, like all reptiles, and have streamlined bodies with large flippers. They are well adapted to life in the ocean and inhabit tropical and subtropical ocean waters around the world. Of the seven species of sea turtles, six are found in U.S. waters; these include the green, hawksbill, Kemp's ridley, leatherback, loggerhead, and olive ridley.

104 Marine Life Essay Topic Ideas & Examples

🏆 best marine life topic ideas & essay examples, 👍 good essay topics on marine life, ⭐ simple & easy marine life essay titles.

• Ocean Pollution and the Fishing Industry In essence, the activities of over six billion people in the world are threatening the survival and quality of water found in the oceans, lakes and other inland water catchment areas.
• The Aral Sea Problems, Their Causes and Consequences To identify and analyze the problems of the lake, its basin, and the entire region To discuss the causes and consequences of the lake’s destruction To evaluate the solutions proposed for ameliorating the consequences The […]
• Climate Change Impacts on Ocean Life The destruction of the ozone layer has led to the exposure of the earth to harmful radiation from the sun. The rising temperatures in the oceans hinder the upward flow of nutrients from the seabed […]
• Marine Parks Concept Overview In terms of marine tourism, aquatic parks offer the best solution for tourists because they are cheaper than watching animals in the sea.
• The Impacts of Oil Spills on Marine Life The intensity of aquatic effects is influenced by the nature and extent of the spilt oil. Besides, the severity might be influenced by the sensitivity and ambient state of the pretentious marine and their surroundings […]
• Life in the Bottom of the Ocean and Its Protection While we all strive hard to detect and analyze the essence of life and the impact it has on our lives, we need to understand that life in itself is a big mystery, the truth […]
• Plastic Waste and Its Effects on Marine Life However, many people do not appreciate the importance of oceans to human and marine life. Another effect of microplastics on the marine community is that they lead to uneven distribution of organisms.
• Living Resources of the Ocean The most commendable among the benefits of marine life to human life are the fact that marine life can act as food and the fact that some oceanic organisms have medicinal value.
• The Indian Ocean Tsunami of 2004 and Its Consequences The worst effects of the great wave were observed in Indonesia, where the death toll exceeded 160,000 people, and the overall damages almost reached $4.
• Marine Life in United Arab Emirates This report analyses the marine life in the UAE, covering detailed information about the various species of animals found in the region and their adaptation to the unique environment.
• Plastic Ocean Pollution on Ocean Life in U.S. Ocean plastic pollution has had a great impact on a minimum of two hundred and sixty seven species across the world and these include forty three percent of all of the sea mammal species, eighty […]
• The Ocean Pollution Problem Overview Ocean pollution is the unfavorable upshot due to the entrance of chemicals and particulate substances into the ocean. The land is the key source of ocean pollution in the form of non-point water pollution.
• Marine Biology: Polar Oceans as an Eco System The water in and around the Antarctic continent is referred to as the Antarctic or Southern Ocean. The Atlantic Water is situated between the Arctic Surface Water and the Arctic Deep Water.
• Habitat and Ocean Life Considerations of Bottlenose Dolphins The temperate and tropical oceans of the world are home to bottlenose dolphins. On the American continent, bottlenose dolphins can be seen along California’s southern beaches and the eastern seaboard from Massachusetts to Florida, and […]
• The Aral Sea’s Environmental Issues Prior to its destruction, the Sea was one of the biggest water bodies, rich in different species of flora and fauna; a case that is opposite today, as the sea is almost becoming extinct.
• Ocean Fisheries Sustainability Analysis It is necessary for fishing industries to use better fishing methods in the ocean to ensure that their activities do not endanger the ecological balance. Fish species do not get the chance to replenish and […]
• Sea Foods in the Environment Protection Context Further, the purpose of the website is to give information that seeks to reward the efforts of people who protect and safeguard the ocean and seafood supplies such as lobsters.
• “History of Ocean Basins” by Hess From the article it is vivid that the coming into being of oceans is subject to discussion since the previous knowledge is doubtful, and the existing framework is confusing.
• Marine Biodiversity Conservation and Impure Public Goods The fact that the issue concerning the global marine biodiversity and the effects that impure public goods may possibly have on these rates can lead to the development of a range of externalities that should […]
• Marine Ecosystems in Oceanography Studies While oceanography students need to understand these aspects of ocean management, this paper focused on marine ecosystems, as a broad and useful topic in oceanography studies.
• The Problem of Ocean Pollution in Modern World Wastes such as toxic matter, plastics, and human wastes are some of the major sources of pollution in the ocean. Many people consume fish as food; when marine life is affected by toxic substance in […]
• How Deep Sea Discoveries Inspires Professional Creativity Limited technological access to the deep seas should inspire one to focus on the necessary technology to build the most efficient deep-sea robots.
• Marine Environment Protection and Management in the Shipping Industry Therefore, criminal penalties system in collaboration with the Environmental Protection Agency should reinforce legislations to protect sea creatures and humans from oil pollution or wastes from ships.
• Marine Creatures and Terrestrial Animals in “The Wild West: Gold Rush” In fact, Californian nature is rich in various animal species that live to survive and pass their genes to the offspring.
• Effect of Sea Water and Corrosion on Concrete On the other hand, substantial tautness, for instance due to meandering will shatter the tiny firm pattern, ending up in fracturing and disjointing of the concrete.
• How the Ocean Current Affect Animals’ Life in the Sea Depending on the strength of the ocean current, sea animals along the path are flown along with the water, and the animals are moved to new regions that are sometimes thousands of kilometers away causing […]
• The Dead Sea Geochemical History Globally, the most saline location is found on the water surfaces and shores of the Dead Sea. On the other hand, the pattern of fluctuation in temperature and salinity in the Arctic Ocean is complex.
• The Ocean’s Rarest Mammal Vaquita – An Endangered Species The vaquita looks like a curved stocky porpoise, and it is the smallest of all the porpoises in the world. This is a matter of concern and ought to be investigated if the survival of […]
• Sea Otters’ Life Cycle From Birth to Death However, after the species had almost become extinct and their protection began, the species began to recover and towards the close of the 20th century, conservation had given rise to tens of thousands of sea […]
• The Negatives of Fossil Fuel: Ocean Acidification and Human Health The adverse effects of burning oil are hard to overestimate. Unless specific and practical actions are taken to address the issues of global climate change and pollution issues and reduce reliance on oil, the future […]
• Impacts of Climate Change on Ocean The development of phytoplankton is sensitive to the temperature of the ocean. Some marine life is leaving the ocean due to the rising water temperature.
• Exploring Environmental Issues: Marine Ecotourism For marine ecotourism to succeed, it must thrive in a manner that accommodates the needs of both the current and future generations and safeguards the natural environment.
• Autonomous Platforms in Marine Research One of the significant ideas that can increase the overall efficiency of the data collection process is the creation of networks of autonomous platforms.
• The Sea Water Impact on the Human Cell Hence, consuming it causes a high amount of salt without the human cell, which leads to a steep concentration gradient within the cell, thereby causing water to be drawn out, which is detrimental to the […]
• Ocean Sustainability and Human Economic Activity The world economy and the livelihoods of hundreds of millions of people depend on the ocean. It is important to remember that the misuse of water resources and the effects of global climate change will […]
• Integrated Coastal Zone Management in the Red Sea and the Gulf of Aden The role of the ICZM in the control of environmental, transport, industrial, and other types of safety is high, and the example of the RSGA region proves this.
• Mining and Ocean Use in Canada Cobalt, nickel, manganese, and copper are among the metals deep seabed mining seeks to extract from the polymetallic nodules on the seafloor and seamounts.
• Addressing Marine Debris: Causes, Effects, and Potential Solutions A major limitation that makes the eradication of the problem difficult is the fact that most of the debris contains microplastic.
• Visiting San Francisco Bay as Marine Protected Area San Francisco Bay Bridge will become the central place for this trip because it is just in the center of this view.
• Non-trophic Interaction in Marine Species An example of non-trophic relationships between marine species is decorator crabs and sponges. Decorator crabs and sponges’ relations are an example of mutually helpful non-trophic interaction mutualism.
• The Rising of Sea Level and Melting Glaciers: Analysis of the Issues In modern realities, the rate of warming of the World’s Oceans has increased. Global warming provokes the melting of ice in Greenland and Antarctica.
• Ocean Dumping Issue and Rhetorical Rationale Therefore, the goal of this paper is to prove that the poster in question manages to accomplish an impressive goal of subverting the audience’s expectation and encouraging them to shift from an ironic perception of […]
• The Ocean Dumping Problem: A Visual Argument There is, however, less awareness of deep-sea drilling and the impacts on the habitat and human life in the oceans and along the coasts.
• Australia’s Endangered Diverse Marine Ecosystem Climate Change and population increase are becoming increasingly difficult to perceive distinctly, especially when the question is about the loss of a diverse marine environment.
• Integrated Ocean Drilling Program Expedition 342 Such flows reduce the temperature of the planet’s core, change the composition of the foundation bedrock, and impact microorganism dispersion in the subterranean ecosystem.
• Ocean Circulation and Biogeography, Species Distribution, Invasive Species The concept of ocean circulation refers to the movements of water in the oceans and seas. Surface ocean currents carry water from the poles to the tropics, where it is heated, and, afterwards, this water […]
• Plastic Ocean and Its Effect on the Ecosystem The purpose of this essay is to present science-based facts in support of the author’s words to convince the reader of the criticality of the ecological problem.
• Marine Protected Areas: Impact on Kelp Forest Recovery and Urchin Reduction The research aims to study the effectiveness of MPA for kelp forest recovery and urchin reduction. The research aims to study the effectiveness of MPA for kelp forest recovery and urchin reduction.
• Environmental Marine Ecosystems: Biological Invasions One of the biggest hypoxic zones in the US is in the Gulf of Mexico. The condition of water in the area caused the decline of the shrimp industry.
• Effects of Global Warming on Marine Life Global warming has adverse effects on the marine life. It has led to the extinction of some of the animals and living things and has been necessitated by human activities.
• Deep-Sea Biology: The Search for a Sea Monster This case study is about the attempts of Clyde Roper to find the giant squid. This canyon is known to be very deep and runs towards the Kermadec Trench which is also documented to be […]
• Bacterial Diseases of Marine Organisms The striped dolphin is a highly susceptible host of the bacteria and poses and the most potent reservoir and source of transmission of the infectious agent.
• Ecotoxicology in the Marmara Sea: A Critical Review The importance and actuality of the paper can not be exaggerated, as the problem of toxic wastes is one of the most burning in Europe.
• Marine Surveying, Inspection and Safety Practices The importance of these conventions and rules was to address the need to access different ports in different countries based on uniform rules and standards acceptable to destination ports or countries in addition to maintaining […]
• How Climate Change Impacts Ocean Temperature and Marine Life The ocean’s surface consumes the excess heat from the air, which leads to significant issues in all of the planet’s ecosystems.
• Dell’s Initiative to Recycle Ocean-Bound Plastics The innovation to use plastics from the ocean and areas where these materials had a high risk of moving to the water was presented to the company in 2015.
• High Seas Marine Protected Areas: Effective Legislation or Paper Parks This essay dwells on the definition and importance of MPAs, including the ones in the high sea. The goal of the alliance is to bolster international collaboration and exchange of knowledge.
• Intergovernmental Relations and Ocean Policy Change The administration of Ronald Reagan contributed to the Federal ocean policy in the 1980s. During this change, analysts believed the United States was making a shift from ocean protection of the 1970s to ocean management […]
• Improving the Response to Marine Emergencies However, we still need to facilitate this process, for instance, by informing the National Fire Service about the implementation of this project and its results. These are the most objectives that have to be attained […]
• A Benchmarking Biodiversity Survey of the Inter-Tidal Zone at Goat Island Bay, Leigh Marine Laboratory Within each quadrant, the common species were counted or, in the case of seaweed and moss, proliferation estimated as a percentage of the quadrant occupied.
• Ocean Circulation in a Warming Climate These effects will enhance the development of reduced release of radio-carbon depleted carbon dioxide gas and thus the idea of the self-restoration mechanism of the earth to this global warming.
• Protected Marine Areas: Great Barrier Reef To protect the Great Barrier Reef the administration has put in place several policies to protect this region. In this plan, A panel of scientists was to advise on the quality of waste.
• Ocean Thermal Energy Conversion The warm seawater is carried into a chamber and is used to produce vapor that, in turn, is used to rotate a turbine.
• Review of the Quaternary History of Reefs in the Red Sea With Reference to Past Sea-Level Changes Some of the changes have occurred on the very grandest of scales, such as the Merging and ensuing breaking up of huge supercontinents, or the decimation of the dinosaurs by extra-terrestrial impacts.reefs are not invulnerable […]
• Radiocarbon C14 Dating in Marine Geology The radiocarbon technique can say to be one of the most important inventions of the 20th century, especially in the field of human science.
• Marine Pollution: Sources, Types, Pathways, and Status By examining sources, types, pathways, and status of water contamination in the context of the World Ocean, it is clear that most marine pollution caused by human actions, especially the mismanagement of plastic debris.
• Concerns of Ocean Ecosystem Pollution The range of adverse outcomes for ocean ecosystems can be discussed in volumes; however, the current discussion will focus on trash in the ocean waters, acidification, and the disruption of the marine life cycles.
• Marine Degradation and Solutions in the Pacific Region The second issue related to the degradation of marine resources in the Pacific region is the unsustainable use of marine resources, including destructive fishing, which leads to changes in the number and health of species.
• Port Philip Bay and Sea Levels in Australia’s Geological History As the scientist explains, the phenomenon of the port’s emergence in the dry environment can be attributed to the fact that considerable water shrinkage could be observed in the area roughly 1,000 years ago.
• Geology: Port Phillip Bay and Sea Level Changes Specifically, the fossils of specific creatures, such as the shells of tertiary foraminifera, as well as the meanders of the river channels, which were located in the area, are bound to bolster the hypothesis suggested […]
• Marine Algae Associated Bacteria as Antioxidants The antinociceptive activity analysis involved comparing the reaction time of mice treated with the extracts and the controls. The authors conclude that the isolation and characterization of the bioactive principles from the potent strains could […]
• Ocean-Plate Tectonics and Geology Bathymetry of the ocean seafloor refers to the measurement of how deep the sea is in relation to the sea level.
• Impact of Sea Transport on the Aquatic Environment The shipping companies also have a serious impact on the maritime environment in terms of the wastes often released into the water.
• Deep-Sea Currents and Upwelling Along Florida The thermohaline circulation influences the movement and population of the marine ecosystem and heat redistribution both in the sea and on the earth’s surface.
• Climate Change Effects on Ocean Acidification The scientists realized that the crisis lasted for several millennia before the oceans could fully recover from the impacts of the drop in the pH level.
• Marine Geology, Hydrology and Human Impact on Earth However, the implementation of the new technologies and practices in the process of investigation of the sea depths resulted in the appearance of the new meaning.
• Marine Ecosystems, Human Dependence and Impact The growth of communities dependent on fishing is proportional to the destruction of marine ecosystems. The survival of the human race, and the survival of millions of species of wildlife is dependent on a healthy […]
• The Northern Sea Route’ Safety Management The company discusses the opportunity to trade some of the vessels with the help of the NSR. The NSR is discussed as an attractive option to decrease the time spent in the voyage while comparing […]
• Water Crisis, Oceans and Sea Turtles Issues In the case of Mexico, it appears that the past regimes have never put a lot of focus on the utilization of water resources.
• SOFAR Effects on the Marine Life The speed and energy of the sounds that are transmitted in the SOFAR channel are maintained without being altered because of the pressure, which increases with increase in depth.
• Ocean Acidification Impact on the Sea Urchin Larval Growth Due to the carbon dioxide increase in the atmosphere, acidity in the oceans is increasing++ and a fast increase of change rate is experienced.
• Deep Sea Mining: Salt Extraction This therefore shows how important the process of evaporation is in regard to extraction of salt from the sea. This therefore explains that sea water is a cheap source of salt in terms of time […]
• Pacific Ocean: Essentials of Oceanography The ocean has about 25,000 islands which are in excess of the entire number islands in all the oceans across the world. The volume of water in the ocean is about 622 million km3.
• El Niño’s Effects on Marine Life El Nino makes the winds of the east blow to the west and moves the layers of warm water in the Pacific Ocean.
• Ecology Issues: Creatures of the Deep Sea Discuss the negative changes that are occurring and the cause of these changes In the recent past, the temperature on the earth has been rising steadily due to the effect of global warming.
• Ocean Literacy and Exploration From the onset of “human-ocean interaction and exploration in the fifteenth century” and despite ocean being the largest feature of the earth, only 5% of the ocean is known.
• Ocean and Atmosphere Circulation Oceanic and atmospheric circulation is the means by which heat is distributed on the surface of the Earth by large scale circulation of air.
• The Role of Sea Power in International Trade The historical influence that the marines or the navy has had on international trade and the complications in comparing measures of sea power has been issues of discussion in the past.
• The Global Ocean Conveyor Belt This ocean water phenomenon is a result of the temperature difference in the ocean waters between the warm, salty surface water, and the less salty cold water in the ocean depths.
• Florida Keys National Marine Sanctuary Reefs This essay addresses some of the disturbances which have been experienced in the coral reefs of the Florida Keys National Marine Sanctuary together with measures which have been implemented to salvage the ecosystem.
• Marine Conservation and Coastal Development The committee should comprise of a balanced membership for holistic review of the coastal development projects. The lack of legislation related to marine conservation is also a major setback.
• Impact of the Toxic Substances on Marine Ecosystem The condition of hypoxia is created when algal biomass decompose leading to dissolution of oxygen in the water column. While, on the other hand, farming of Bluefin tuna leads to destruction of marine life as […]
• Climate Shift Could Leave Some Marine Species Homeless This is very important as it helps put pressure on countries to reduce on carbon release, in order to conserve the environment and hence species at risk.
• Global Warming Outcomes and Sea-Level Changes The outcome of global warming has been exhibited by the melting of ice and snows in areas such as the Antarctic which has changed the average sea level of the whole world because the ice […]
• Deep Sea Volcanoes and their Effects Deep sea volcanoes are present under deep sea ridges of the ocean floor and the above research has been based on the amount of carbon dioxide that is present in depths of four kilometers on […]
• Policy Change to Control Ocean Dumping Policies addressing the issue of ocean dumping and the need to curb it have been in place. Several factors fueled the change; for instance, change in the information concerning the effect of ocean dumping to […]
• Coral Reef Essay Topics
• Hunting Questions
• Moby Dick Questions
• Landfill Essay Titles
• Pollution Essay Ideas
• Tsunami Essay Ideas
• Biodiversity Research Topics
• Fishing Research Topics
• Chicago (A-D)
• Chicago (N-B)

IvyPanda. (2024, February 29). 104 Marine Life Essay Topic Ideas & Examples. https://ivypanda.com/essays/topic/marine-life-essay-topics/

"104 Marine Life Essay Topic Ideas & Examples." IvyPanda , 29 Feb. 2024, ivypanda.com/essays/topic/marine-life-essay-topics/.

IvyPanda . (2024) '104 Marine Life Essay Topic Ideas & Examples'. 29 February.

IvyPanda . 2024. "104 Marine Life Essay Topic Ideas & Examples." February 29, 2024. https://ivypanda.com/essays/topic/marine-life-essay-topics/.

1. IvyPanda . "104 Marine Life Essay Topic Ideas & Examples." February 29, 2024. https://ivypanda.com/essays/topic/marine-life-essay-topics/.

Bibliography

IvyPanda . "104 Marine Life Essay Topic Ideas & Examples." February 29, 2024. https://ivypanda.com/essays/topic/marine-life-essay-topics/.

By visiting our site, you agree to our privacy policy regarding cookies, tracking statistics, etc.

• For Animals
• For Your Health
• For The Planet
• For Humanity
• For Spirituality
• To Prevent Pandemics
• Busting Vegan Myths
• Veganism For All
• On A Budget
• For Athletes
• For Pregnancy And Parenting
• In Older Age
• While Honoring Our Culture
• Earthshot Prize
• Film Production
• Outreach & Events
• Make An Impact

What Is Marine Life And Its Importance? Facts & Statistics

Reading time: 8 minutes

The Earth’s oceans are home to millions of animal and plant species, as well as potentially millions more that are so far undiscovered. They are delicately balanced ecosystems and their healthy function is key to the balance of all life on Earth. Many people see marine life as something altogether separate to life on land but the two are far more connected than we might think. Crucially, the behavior and choices made by people seriously impact the wellbeing of our aquatic friends.

What Is Marine Life?

Marine life refers to all the animals, plants and organisms that live in Earth’s saltwater seas and oceans. From the smallest plankton to the largest whale, all organisms play a role in the healthy function of these amazing, complex ecosystems.

Coral Reef Ecosystems

Coral reefs are diverse, colorful and home to millions of marine species across the planet. They provide a natural barrier to the power of the ocean, protecting coastal communities from extreme weather events such as tsunamis. As food chains, they are extremely important, providing an area in which marine species can live, feed, raise their young and thrive.

Unfortunately, they are also highly vulnerable to ocean temperature change, a direct result of climate breakdown. In 2016, Australia’s Great Barrier Reef experienced a 30 percent loss of coral reef due to a nine-month marine heatwave, the largest reef loss ever recorded. The fishing of reefs has also led to species loss, as food chains are interrupted and predators cannot survive.

Some examples of the largest reef ecosystems on earth include:

• The Great Barrier Reef, Australia
• The Red Sea Reef, Egypt, Sudan and Eritrea
• New Caledonia Barrier Reef, southwest Pacific Ocean
• Florida Reef, USA
• Andros Coral Reef, the Bahamas

Ocean Fishes

There are thousands of different species of ocean fish, yet populations are continually declining as we allow commercial fleets to fish our oceans. Atlantic cod, for example, can live up to 25 years, yet their populations are now at critically low levels. Some other ocean fish include:

• Barramundis

Marine Mammals

Marine mammals are generally larger sea creatures, who live underwater but need to breathe air also. Around the world these marine mammals still lose their lives unnecessarily due to habitat loss, being caught and killed by fishing fleets (“ fishing bycatch ”), hunting and noise pollution.

• Marine mammals include:

Sea Turtles And Reptiles

Reptile life in the sea is largely made up of turtle species such as:

• Loggerhead turtles
• Hawksbill sea turtles
• Green sea turtles
• Leatherback sea turtles

All seven species of sea turtles are endangered or critically endangered with The World Wildlife Fund stating that “the single biggest threat to most sea turtles is fishing gear.”

Marine iguanas and saltwater crocodiles are also ocean-dwelling species of reptile. Reptilian life in the sea is particularly vulnerable to pollutants such as plastic, as these animals live in shallow seas and come into contact with human populations often.

Cephalopods, Crustaceans And Shellfish

Cephalopods, crustaceans and shellfish play an important role in ocean ecosystems and the marine food chains, and includes:

• Cuttlefishes

They are particularly vulnerable to increased ocean acidification, a direct result of increased human-generated greenhouse gas emissions.

Seabirds are found on coastlines, in coastal waters and far out at sea, and include species such as:

• Albatrosses
• Fish eagles

Seabirds play a vital role in marine ecosystems but populations have dropped by 70 percent since the middle of the 20th century, with campaigners saying that they are being pushed to the brink of extinction by the fishing industry. Habitat destruction and pollution also play a part.

Why Marine Life Is Important?

The oceans provide 50 percent of the world’s oxygen and they provide essential ecosystem services that allow our planet to function in a healthy way. For example, ocean currents govern our weather systems, and if they were to be interrupted, the extreme weather consequences would be drastic. The oceans can only provide these services by maintaining delicately balanced ecosystems, made up of food chains and biological systems. Human activity risks the shutdown of essential ecosystem services that we rely on to survive.

One example is coral reefs. When we fish around coral reefs, those reefs’ delicate ecosystems are damaged and often die. We then lose the essential service a coral reef provides such as protection from erosion and weather, biochemical regulation, and recreation. This is just one of the reasons why taking care of the oceans is essential for our own wellbeing.

Marine Life Facts And Statistics

• An estimated 50-70 percent of all life on Earth is found under the oceans
• Humans have explored roughly 10-20 percent of the ocean
• There are around 230,000 classified marine species, but as many as two million or more yet to be discovered
• Marine biodiversity is declining at an alarming rate. It is estimated the oceans suffered around a 50 percent species loss between 1970 and 2012

Marine Life Pollution

Humans continue to pollute the oceans, despite the huge risks to marine life and to ourselves. Marine pollution comes in many forms such as plastic pollution, acidification and oil spills.

How Does Ocean Acidification Affect Marine Life?

Ocean acidification occurs due to increases in carbon dioxide in the atmosphere (due to climate warming) and it can have terrible consequences for marine life, particularly crustaceans. Higher acidity in water results in shells dissolving more quickly, which of course has a devastating impact on shellfish and other crustaceans. This can have drastic knock-on consequences for other animals who rely on them for food, and throw marine food chains and whole ecosystems out of balance..

How Do Fisheries And Seafood Affect Marine Life?

Probably the largest risk posed to marine life is the fishing industry. Vast commercial fleets trawling the oceans has been common practice for many years and sadly shows no signs of slowing. The negative impacts for marine life are huge and includes:

• Fish population crashes which impacts every species that live in the oceans. Bycatch from fishing nets results in huge biodiversity loss, including driving species to the brink of extinction.
• There is evidence to show that catching fish causes pain and is hugely distressing for those caught and those left behind.

How Does Fish Farming Affect Marine Life?

Fish farming poses various environmental and welfare risks including:

• Disease is easily spread in fish farms and too often spreads beyond the farm into the natural environment.
• Fish farms pollute waters with the chemicals needed to treat diseases caused by the appalling conditions, excess feed and concentrated fish waste. This pollution causes algal blooms, resulting in the deaths of wild fish, too.
• Wild marine animals, such as seals, are inevitably attracted to fish farms as a potential source of food, but these animals are often killed deliberately by farmers to stop them eating the valuable fish.

How Does Human-generated Noise Pollution Affect Marine Life?

Natural soundscapes in the ocean are key for healthy marine life, as animals use sound to communicate, catch food, navigate, defend themselves and attract mates. Machinery like boats, jet skis or oil drills create an unnatural barrier to marine life’s natural soundscape, and the impacts can devastating:

• Marine mammals like whales use complex songs to communicate, navigate and attract one another. If these are interrupted, they cannot enact basic natural functions and die as a consequence
• Animals can be directly stressed by unnatural noise, leading them to make poor decisions that can lead to their deaths

Other Forms Of Pollution?

Plastic pollution is the other major form of marine pollution that affects marine life:

• Plastic waste can entrap marine animals resulting in them drowning, starving or being eaten
• Soft plastics and microplastics can be ingested by marine life and cause their deaths
• Plastic pollution kills 100 million marine mammals and up to a million seabirds every year
• Most plastic pollution comes from the fishing industry

How Can We Save Marine Life?

Put simply, we can save marine life by leaving the oceans alone and letting their ecosystems operate naturally. These systems have developed over millions of years of evolution and they can only operate without our intrusion.

We can reduce our impact on marine life in a few ways:

• Go vegan. Stopping consumption of marine animals is the single biggest way to help the oceans. It would stop overfishing and bycatch, returning fish populations to healthy levels. It would also reduce noise pollution from fishing vessels, reduce oil spills and plastic pollution from fishing fleets, and lower carbon dioxide levels, thereby reducing ocean acidification
• Reduce our consumption of all unnecessary products and buy local as much as we can – global shipping networks create noise and chemical pollution in the oceans, which directly affects marine life
• Reduce our reliance on plastics, stop buying single-use plastic items, and recycle plastic waste effectively, so that it never ends up in the ocean
• Raise awareness of the issues – watch and share documentaries such as Seaspiracy to alert others of the need to save marine life

Healthy marine life is critical to the healthy function of the whole planet and to the lives of all those who inhabit it. Without healthy balanced oceans, many of our essential ecosystem services would collapse, resulting in terrible knock-on effects for humans and animals alike. But that is not the only reason to protect marine life. We should protect them for their own sake. The lives of marine animals are as important to them as ours are to us. They are here on Earth with us, not for us.

More from the blog

Vegan Meat: 13 Vegan Meat Substitutes & Where To Find It

New Year’s Day 2022: Five Reasons Why Going Vegan is the Best New Year’s Resolution and Six Ways to Do It

How to Survive Being Vegan at Christmas & What do Vegans Eat?

Ready to go vegan, already vegan, take our challenge.

• We have 7-day and 30-day vegan challenges.
• Suitable for children, adults and athletes.
• Daily inspiration, recipes, facts and videos.

What It Would Take to See the World Completely Differently

The marine biologist Rachel Carson saw immense value in helping the public cultivate a sense of wonder.

W hen the marine biologist Rachel Carson was a young girl, she discovered a fossilized shell while hiking around her family’s hillside property in Springdale, Pennsylvania. Those who knew her then would later contend that this relic sparked such intense reverie in her that she instantly felt a tug toward the sea. What was this ancient creature, and what was the world it had known?

Though Carson had never seen the sea herself, she threw herself into its study. She studied biology, then zoology, eventually taking a job as a writer for the U.S. Bureau of Fisheries. All of this was incredibly rare for a young woman in the 1920s and ’30s, but Carson’s trajectory was a demonstration of the expansive potential of curiosity. It also reflected the tireless tutelage of her mother, Maria, who had instilled a love of the wild in her children by regularly taking them on walks to learn about botany and birds. Carson absorbed these lessons and, throughout her life, maintained a deep conviction that wonder had to be at the foundation of any relationship with nature.

In her final months, Carson, age 56, sickened from cancer treatments and in constant pain, still had a couple of remaining projects in mind. One of these was what she called the “wonder book.” By that point, Carson had already written four best-selling books, most famously Silent Spring , which documented the dangers of pesticides, including DDT, and is now widely credited with catalyzing the modern environmental movement. Yet Carson felt she had one more thing to say. The “wonder book”—published posthumously as The Sense of Wonder —was based on a lyrical essay about the importance of cultivating wonder in children. Perhaps because of her early experience, Carson placed great faith in this emotional response that, once found, could serve as “an unfailing antidote against the boredom and disenchantments of later years, the sterile preoccupation with things that are artificial.” Wonder led to a sense of the beautiful, which led to the pursuit of knowledge about the object that triggered the feeling in the first place. Children possessed this “clear-eyed vision” innately, but it had to be kept alive. Adults could awaken this quality in themselves too. With enough attention, she argued, anyone could “feel the rain on [their] face and think of its long journey, its many transmutations, from sea to air to earth.”

Read: Swimming in the wild will change you

Why did Carson feel so strongly the need to proselytize the wonders of wonder? Perhaps she sensed that, without it, an emotional connection with nature would be impossible; without it, the environmental movement had no hope. “The more clearly we can focus our attention on the wonders and realities of the universe,” she once said, “the less taste we shall have for the destruction of our race.” Today, we remember Carson for her crusading spirit and moral clarity; we cite Silent Spring as an example of a political book that spurred public outrage and prodded the government toward action. However, we far less frequently remember Carson for this other thing she spent her whole life doing: helping the public cultivate a sense of awe about nature. To see this facet of her sensibility most clearly, we need to return to her first three books— The Sea Trilogy .

I t was April 1936. Dust storms thundered across the plains of Texas and Oklahoma, Nazi Germany had reoccupied the Rhineland a month earlier, and the Spanish Civil War would soon erupt. Meanwhile, in Washington, D.C., Carson had just turned in a draft of her latest essay, titled “The World of Waters.” Her assignment at the U.S. Bureau of Fisheries had been to write an introduction for a government brochure on fish. The year before, she had helped write a radio series informally dubbed “seven-minute fish tales,” a deceptively difficult job that had confounded other employees who either knew hard science or knew how to write but couldn’t merge the two. Rachel Carson, it turned out, could. As her supervisor, Elmer Higgins, read the draft, Carson sat quietly in his cramped office and nervously awaited his verdict. “I don’t think it will do,” she later recalled him saying when he looked up again, with a “twinkle in his eye.” These pages were not suitable for a government brochure on fish, he continued. No. This was literature. He passed the pages back to her and said, “Better try again. But send this one to The Atlantic .”

A version of that essay was published in this magazine a year later, titled “Undersea.” The editor who accepted Carson’s essay praised it for illuminating science “in such a way as to fire the imagination of the layman.” Lively, lyrical, and exactingly researched, the essay showcased what would soon be recognized as her signature style to a national audience. Here was her abiding emphasis on ecology and life cycles—and her commitment to making the reader feel something. She strove to educate, and to astonish. She deftly manipulated sound, rhythm, and atmosphere. Life on the ocean floor was described as in a moody noir, bathed in perpetual “bluish twilight” where “swarms of diminutive fish twinkle through the dusk like a silver rain of meteors, and eels lie in wait among the rocks.” The mid-ocean lulled with its “lilt of the long, slow swells,” while at the shore, the aptly accented “foam and surge of the tide” beat relentlessly upon its sturdy little inhabitants. Determined to avoid what she later called the “human bias” of popular science writing, Carson sought to portray the world of waters solely from a creaturely perspective, urging readers to “shed [their] human perceptions.”

By Carson’s own estimation, from the publication of “Undersea,” “everything else followed.” Her career as a poet of the sea unfurled. Carson went on to write three best-selling books about the sea: Under the Sea-Wind (1941), adapted from “Undersea”; The Sea Around Us (1951); and The Edge of the Sea (1955). These three books make up her Sea Trilogy , recently reissued by Library of America. Under the Sea-Wind was, Carson thought, her “first real act of literary creation.” It stands out in her body of work for its genre-breaking creative daring—reading more like an adventure novel than a book of science. Written from a close-third-person omniscient point of view, interweaving the perspectives of different (named) animal characters, it animates the life stories of Rynchops the skimmer, the sanderling couple Blackfoot and Silverbar, and Anguilla the eel. We see them struggling to survive, making a life, battling harsh weather, feeding, fleeing, and embarking upon their final journeys to mate and then die. Today we are familiar with the high-definition, IMAX version of what Carson conjured through language—the swoops of riveting pursuit and slow-motion escapes of the nature documentary. That she honed her storytelling chops while writing the public-service equivalent of bingeable TV is unsurprising. About 80 years later, Sea-Wind still reads like a scintillating adventure tale. Reviews from scientists and nonscientists alike praised it for its “lyrical beauty” and “faultless science,” “so skillfully written as to read like fiction.”

Carson wanted not just to entertain but also to impart an abiding sense of interconnectedness. In a section of Sea-Wind about the reawakening of life on spring seas (yes, seas have seasons too, I learned), Carson pulls us in to witness the great seasonal mackerel spawn, a “sprawling river of life, the sea’s counterpart of the river of stars that flows through the sky at the Milky Way.” There, we are introduced to one mackerel, whom Carson cheekily names “Scomber.” ( Scomber is a genus of fish, known as one of the “true mackerels.”) We see Scomber’s conception, his development from an egg floating passively on the sea, his formation of a backbone. Alone, he must evade the hungry mouths of anchovies who are themselves hunted by larger bluefish. Crossing the murky depths, he’s soon caught in the grasp of a “shimmering oval globe”—the comb jelly Pleurobrachia . But before he’s sucked into its pulsing mouth—nail-biting tension here!—the comb jelly and Scomber are both unexpectedly trapped in the mouth of a sea trout, who fortunately spits them both out after a few experimental bites.

The sequence is thrilling, while showing in immersive detail the workings of one food chain among innumerable others in the ocean. Though there is little sentimentality here about the death of any particular creature—everything, whether plankton or fish or mollusk, is always eating or being eaten—there is a sense of horror at human plunder. The sheer scale of what humans took for themselves is what made them monstrous. Carson opts to portray the ravage of resources indirectly, through mood and insinuation. We zoom in—something is amiss. Coming over the plateau, Scomber and his companions see some large haddock caught, “turning and twisting slowly on the hooks that they had swallowed.” Narrowly evading this gruesome scene, the mackerel then confront another threat looming from below: a trawl net, a “cavernous bag” scooping up thousands of pounds of life from the ocean floor.

Read: Netflix’s Our Planet says what other nature series have omitted

After spending all of Scomber’s life with him, how could the reader not feel for him, root for him? Narrating from the point of view of animal protagonists is a classic technique that builds empathy bridges, but in this case it’s done without the purely commercial manipulations of, say, Disney movies. Instead, a different political agenda is at work. The violence inherent in extractive capitalism and the particular logic that allows for some lives to be rendered utterly dispensable is intimated rather than stated. Can Scomber persist? At the end of the mackerel chapter, Carson floats away from the besieged mackerel’s mind and into the mind of a young fisherman on the deck of a boat, who’s been at sea for only two years:

He sometimes thought about fish as he looked at them on deck or being iced down in the hold. What had the eyes of the mackerel seen? Things he’d never see; places he’d never go. He seldom put it into words, but it seemed to him incongruous that a creature that had made a go of life in the sea, that had run the gauntlet of all the relentless enemies that he knew roved through that dimness his eyes could not penetrate, should at last come to death on the deck of a mackerel seiner, slimy with fish gurry and slippery with scales.

What had the eyes of the mackerel seen? How was it that this mackerel, who had “run the gauntlet” of the sea, should end life in this ignoble way? The young fisherman is confronting these ecological questions firsthand, asking the questions that Carson would like us to ask. And now that we’ve experienced what the mackerel saw and the fisherman wondered—what follows?

I f Carson’s sea books can serve a “utilitarian” purpose today, guesses Sandra Steingraber, an environmental activist and the editor of the new Sea Trilogy edition, they mark a “disappearing natural baseline” that describes “how the all-creating ocean functioned, how its creatures lived and interacted.” As I read, I noted, sadly, all the past-tense verbs in that sentence. Is it already too late to know the sea as Carson once did? In her introduction, Steingraber goes on to list the currently unfolding catastrophes that Carson never lived to see: “industrial overfishing, or news of the potential collapse of the Gulf Stream, or massive floating garbage patches, or icebergs the size of states breaking off Antarctica, or micro-plastics replacing plankton in the water column, or plans for deep-sea mining.” To that list one might add ocean acidification, hypoxic dead zones, sonar testing, and coral die-off. Steingraber strains for some silver lining: “But her words fortify us for battles” and—she sums things up waveringly—“inspire curiosity and care about what we are in the process of losing.”

Is wonder still possible, given our climate crisis? Wonder implies some degree of leisure and time; it requires slow, sustained, and contemplative attention—a luxury that, perhaps, we can no longer afford. Even Carson, when she wrote the new preface for the revised 1961 edition of The Sea Around Us , couldn’t help but inject an urgent warning about the practice of dumping nuclear waste into the ocean. She called the previous assurance that the sea was so large as to be inviolate a “naive” belief. Today, as dire emergencies unfold, rationalizing time spent merely appreciating the natural world seems even more difficult. During the COP26 climate conference, protesters held up signs spelling doom and chanted: “If not now, when? When?” Greta Thunberg summarily declared the conference a failure, dismissing it as a meaningless PR event for “beautiful speeches.”

Read: The dark side of the houseplant boom

The climate crisis requires urgency on a global scale: Countries need to act, policies need to be set in motion. But slowness is needed as well. As the writer Naomi Klein points out in On Fire: The (Burning) Case for a Green New Deal , our “culture of the perpetual present” is not equipped to deal with the generations-long nature of the crisis. Market forces compel us to speed up precisely when we need to take a beat; to insulate ourselves from the physical environment precisely when we need to develop a more intimate connection. Modern life guarantees the atrophy of important “observational tools,” Klein writes; rather than stopping someplace to get to know its rhythms and cycles, we sever and uproot ourselves by living through screens and portals. All of this helps maintain the harmful illusion that if one environment gets destroyed, there will always be some other “away” to escape into.

In our day-to-day lives, pure enjoyment of nature can seem somehow suspect or unproductive, and the justification of such time spent is often couched in utilitarian or economic terms. Walks are for clearing heads; hikes are good exercise. Carson anticipated this line of thinking. In The Sense of Wonder , she asks rhetorically, “What is the value of preserving and strengthening this sense of awe and wonder … ? Is [it] just a pleasant way to pass the golden hours of childhood, or is there something deeper?” Though we tend to think of the American mid-century as a time of prosperity and advancement— perhaps they had time to wonder, but we don’t —it was, in fact, equally plagued with existential emergencies: the Cold War, McCarthyism, segregation and intractable racism. Stopping to wonder seemed frivolous back then too. Carson’s rebuttal, rousing and powerful, argues that wonder provides no less than joy, hope, and inner strength in the face of despair and annihilation:

Those who dwell … among the beauties and mysteries of the earth are never alone or weary of life. Whatever the vexations or concerns of their personal lives, their thoughts can find paths that lead to inner contentment and to renewed excitement in living. Those who contemplate the beauty of the earth find reserves of strength that will endure as long as life lasts. There is symbolic as well as actual beauty in the migration of the birds, the ebb and flow of the tides, the folded bud ready for the spring. There is something infinitely healing in the repeated refrains of nature—the assurance that dawn comes after night, and spring after the winter.

Trusting in wonder’s resonant effects is something akin to faith. Fear can be motivating, but so can love. Taking a cue from Carson, I’ve been trying to take more walks with open eyes and an open heart, unpracticed as I may be. I treat myself like a child and go around with a pair of binoculars. After reading that the spring migration of birds is again in full swing, one night during a full-ish moon, I took my binoculars and sat out on the stoop. One of the fun activities that Carson recommends is to point the lens to the moon to see if you can catch the silhouettes of migrating birds as they pass across its shining face. I also listened hard to detect the “wisps of sound,” the “sharp chirps, sibilant lisps, and call notes” of eager flocks. Instead, I heard trucks clattering down I-95 and my neighbor wheeling his garbage out. After about half an hour, I brushed off my pants and headed back inside. It hadn’t been a spectacular experience by any means, but, maybe because I had strained so long to hear them and see them, I dreamed of the birds that night. In my mind’s eye, an endless, exuberant procession of birds passed high above the sleeping city, dipping in and out of the moonlit clouds, calling to one another from darkness to darkness. They were sure of their destination, unwavering.

​When you buy a book using a link on this page, we receive a commission. Thank you for supporting The Atlantic.

About the Author

More Stories

Swimming in the Wild Will Change You

All About the Ocean

The ocean covers 70 percent of Earth's surface.

Biology, Earth Science, Oceanography, Geography, Physical Geography

Loading ...

This article is also available in Spanish .

The ocean covers 70 percent of Earth 's surface. It contains about 1.35 billion cubic kilometers (324 million cubic miles) of water, which is about 97 percent of all the water on Earth. The ocean makes all life on Earth possible, and makes the planet appear blue when viewed from space. Earth is the only planet in our solar system that is definitely known to contain liquid water. Although the ocean is one continuous body of water, oceanographers have divided it into five principal areas: the Pacific, Atlantic, Indian, Arctic, and Southern Oceans. The Atlantic, Indian, and Pacific Oceans merge into icy waters around Antarctica. Climate The ocean plays a vital role in climate and weather . The sun’s heat causes water to evaporate , adding moisture to the air. The oceans provide most of this evaporated water. The water vapor condenses to form clouds, which release their moisture as rain or other kinds of precipitation . All life on Earth depends on this process, called the water cycle . The atmosphere receives much of its heat from the ocean. As the sun warms the water, the ocean transfers heat to the atmosphere. In turn, the atmosphere distributes the heat around the globe. Because water absorbs and loses heat more slowly than land masses, the ocean helps balance global temperatures by absorbing heat in the summer and releasing it in the winter. Without the ocean to help regulate global temperatures, Earth’s climate would be bitterly cold. Ocean Formation After Earth began to form about 4.6 billion years ago, it gradually separated into layers of lighter and heavier rock. The lighter rock rose and formed Earth’s crust . The heavier rock sank and formed Earth’s core and mantle . The ocean’s water came from rocks inside the newly forming Earth. As the molten rocks cooled, they released water vapor and other gases. Eventually, the water vapor condensed and covered the crust with a primitive ocean. Today, hot gases from the Earth’s interior continue to produce new water at the bottom of the ocean. Ocean Floor Scientists began mapping the ocean floor in the 1920s. They used instruments called echo sounders , which measure water depths using sound waves . Echo sounders use sonar technology. Sonar is an acronym for SOund Navigation And Ranging. The sonar showed that the ocean floor has dramatic physical features, including huge mountains, deep canyons , steep cliffs , and wide plains . The ocean’s crust is a thin layer of volcanic rock called basalt . The ocean floor is divided into several different areas. The first is the continental shelf , the nearly flat, underwater extension of a continent. Continental shelves vary in width. They are usually wide along low-lying land, and narrow along mountainous coasts. A shelf is covered in sediment from the nearby continent. Some of the sediment is deposited by rivers and trapped by features such as natural dams. Most sediment comes from the last glacial period , or Ice Age, when the oceans receded and exposed the continental shelf. This sediment is called relict sediment . At the outer edge of the continental shelf, the land drops off sharply in what is called the continental slope . The slope descends almost to the bottom of the ocean. Then it tapers off into a gentler slope known as the continental rise. The continental rise descends to the deep ocean floor, which is called the abyssal plain . Abyssal plains are broad, flat areas that lie at depths of about 4,000 to 6,000 meters (13,123 to 19,680 feet). Abyssal plains cover 30 percent of the ocean floor and are the flattest feature on Earth. They are covered by fine-grained sediment like clay and silt. Pelagic sediments, the remains of small ocean organisms, also drift down from upper layers of the ocean. Scattered across abyssal plains are abyssal hills and underwater volcanic peaks called seamounts. Rising from the abyssal plains in each major ocean is a huge chain of mostly undersea mountains. Called the mid-ocean ridge , the chain circles Earth, stretching more than 64,000 kilometers (40,000 miles). Much of the mid-ocean ridge is split by a deep central rift, or crack. Mid-ocean ridges mark the boundaries between tectonic plates . Molten rock from Earth’s interior wells up from the rift, building new seafloor in a process called seafloor spreading . A major portion of the ridge runs down the middle of the Atlantic Ocean and is known as the Mid-Atlantic Ridge. It was not directly seen or explored until 1973. Some areas of the ocean floor have deep, narrow depressions called ocean trenches . They are the deepest parts of the ocean. The deepest spot of all is the Challenger Deep , which lies in the Mariana Trench in the Pacific Ocean near the island of Guam. Its true depth is not known, but the most accurate measurements put the Challenger Deep at 11,000 meters (36,198 feet) below the ocean’s surface—that’s more than 2,000 meters (6,000 feet) taller than Mount Everest, Earth’s highest point. The pressure in the Challenger Deep is about eight tons per square inch.

Ocean Life Zones From the shoreline to the deepest seafloor, the ocean teems with life. The hundreds of thousands of marine species range from microscopic algae to the largest creature to have ever lived on Earth, the blue whale. The ocean has five major life zones, each with organisms uniquely adapted to their specific marine ecosystem . The epipelagic zone (1) is the sunlit upper layer of the ocean. It reaches from the surface to about 200 meters (660 feet) deep. The epipelagic zone is also known as the photic or euphotic zone, and can exist in lakes as well as the ocean. The sunlight in the epipelagic zone allows photosynthesis to occur. Photosynthesis is the process by which some organisms convert sunlight and carbon dioxide into energy and oxygen . In the ocean, photosynthesis takes place in plants and algae. Plants such as seagrass are similar to land plants—they have roots, stems, and leaves. Algae is a type of aquatic organism that can photosynthesize sunlight. Large algae such as kelp are called seaweed . Phytoplankton also live in the epipelagic zone. Phytoplankton are microscopic organisms that include plants, algae, and bacteria. They are only visible when billions of them form algal blooms , and appear as green or blue splotches in the ocean. Phytoplankton are a basis of the ocean food web . Through photosynthesis, phytoplankton are responsible for almost half the oxygen released into Earth’s atmosphere. Animals such as krill (a type of shrimp), fish, and microscopic organisms called zooplankton all eat phytoplankton. In turn, these animals are eaten by whales, bigger fish, ocean birds, and human beings. The next zone down, stretching to about 1,000 meters (3,300 feet) deep, is the mesopelagic zone (2). This zone is also known as the twilight zone because the light there is very dim. The lack of sunlight means there are no plants in the mesopelagic zone, but large fish and whales dive there to hunt prey . Fish in this zone are small and luminous . One of the most common is the lanternfish, which has organs along its side that produce light. Sometimes, animals from the mesopelagic zone (such as sperm whales ( Physeter macrocephalus ) and squid) dive into the bathypelagic zone (3), which reaches to about 4,000 meters (13,100 feet) deep. The bathypelagic zone is also known as the midnight zone because no light reaches it. Animals that live in the bathypelagic zone are small, but they often have huge mouths, sharp teeth, and expandable stomachs that let them eat any food that comes along. Most of this food comes from the remains of plants and animals drifting down from upper pelagic zones. Many bathypelagic animals do not have eyes because they are unneeded in the dark. Because the pressure is so great and it is so difficult to find nutrients , fish in the bathypelagic zone move slowly and have strong gills to extract oxygen from the water. The water at the bottom of the ocean, the abyssopelagic zone (4), is very salty and cold (2 degrees Celsius, or 35 degrees Fahrenheit). At depths up to 6,000 meters (19,700 feet), the pressure is very strong—11,000 pounds per square inch. This makes it impossible for most animals to live. Animals in this zone have bizarre adaptations to cope with their ecosystem. Many fish have jaws that look unhinged. The jaws allow them to drag their open mouth along the seafloor to find food, such as mussels, shrimp, and microscopic organisms. Many of the animals in this zone, including squid and fish, are bioluminescent. Bioluminescent organisms produce light through chemical reactions in their bodies. A type of angler fish, for example, has a glowing growth extending in front of its huge, toothy mouth. When smaller fish are attracted to the light, the angler fish simply snaps its jaws to eat its prey. The deepest ocean zone, found in trenches and canyons, is called the hadalpelagic zone (5). Few organisms live here. They include tiny isopods , a type of crustacean related to crabs and shrimp. Invertebrates such as sponges and sea cucumbers thrive in the abyssopelagic and hadalpelagic zones. Like many sea stars and jellyfish, these animals are almost entirely dependent on falling parts of dead or decaying plants and animals, called marine detritus . Not all bottom dwellers, however, depend on marine detritus. In 1977, oceanographers discovered a community of creatures on the ocean floor that feed on bacteria around openings called hydrothermal vents. These vents discharge superheated water enriched with minerals from Earth’s interior. The minerals nourish unique bacteria, which in turn nourish creatures such as crabs, clams, and tube worms. Ocean Currents Currents are streams of water running through a larger body of water. Oceans, rivers, and streams have currents. The ocean’s salinity and temperature and the coast’s geographic features determine an ocean current’s behavior. Earth’s rotation and wind also influence ocean currents. Currents flowing near the surface transport heat from the tropics to the poles and move cooler water back toward the Equator . This keeps the ocean from becoming extremely hot or cold. Deep, cold currents transport oxygen to organisms throughout the ocean. They also carry rich supplies of nutrients that all living things need. The nutrients come from plankton and the remains of other organisms that drift down and decay on the ocean floor. Along some coasts, winds and currents produce a phenomenon called upwelling . As winds push surface water away from shore, deep currents of cold water rise to take its place. This upwelling of deep water brings up nutrients that nourish new growth of plankton, providing food for fish. Ocean food chains constantly recycle food and energy this way.

Some ocean currents are enormous and extremely powerful. One of the most powerful is the Gulf Stream , a warm surface current that originates in the tropical Caribbean Sea and flows northeast along the eastern coast of the United States. The Gulf Stream measures up to 80 kilometers (50 miles) wide and is more than a kilometer (3,281 feet) deep. Like other ocean currents, the Gulf Stream plays a major role in climate. As the current travels north, it transfers moisture from its warm tropical waters to the air above. Westerly, or prevailing, winds carry the warm, moist air to the British Isles and to Scandinavia , causing them to have milder winters than they otherwise would experience at their northern latitudes . Northern parts of Norway are near the Arctic Circle but remain ice-free for most of the year because of the Gulf Stream. The weather pattern known as El Niño includes a change to the Humboldt Current (also called the Peru Current) off the western coast of South America. In El Niño conditions, a current of warm surface water travels east along the Equator and prevents the normal upwelling of the cold, nutrient-rich Humboldt Current. El Niño, which can devastate the fisheries of Peru and Ecuador, occurs every two to seven years, usually in December. The paths of ocean currents are partially determined by Earth’s rotation. This is known as the Coriolis effect . It causes large systems, such as winds and ocean currents that would normally move in a straight line, to veer to the right in the northern hemisphere and to the left in the southern hemisphere . People and the Ocean For thousands of years, people have depended on the ocean as a source of food and as a route for trade and exploration . Today, people continue to travel on the ocean and rely on the resources it contains. Nations continue to negotiate how to determine the extent of their territory beyond the coast. The United Nations’ Law of the Sea treaty established exclusive economic zones (EEZs), extending 200 nautical miles (230 miles) beyond a nation’s coastline. Even though some countries have not signed or ratified the treaty (including the U.S.), it is regarded as standard. Russia has proposed extending its EEZ beyond 200 nautical miles because two mid-ocean ridges, the Lomonosov and Medeleev Ridges, are extensions of the continental shelf belonging to Russia. This territory includes the North Pole. Russian explorers in a submersible vehicle planted a metal Russian flag on the disputed territory in 2007. Through the centuries, people have sailed the ocean on trade routes . Today, ships still carry most of the world’s freight , particularly bulky goods such as machinery, grain, and oil . Ocean ports are areas of commerce and culture. Water and land transportation meet there, and so do people of different professions: businesspeople who import and export goods and services; dockworkers who load and unload cargo ; and ships’ crews. Ports also have a high concentration of migrants and immigrants with a wide variety of ethnicities, nationalities, languages, and religions. Important ports in the U.S. are New York/ New Jersey and New Orleans. The busiest ports around the world include the Port of Shanghai in China and the Port of Rotterdam in the Netherlands. Ocean ports are also important for a nation’s armed forces. Some ports are used exclusively for military purposes, although most share space with commercial businesses. “The sun never sets on the British Empire” is a phrase used to explain the scope of the empire of Great Britain , mostly in the 19th century. Although based on the small European island nation of Great Britain, British military sea power extended its empire from Africa to the Americas, Asia, and Australia. Scientists and other experts hope the ocean will be used more widely as a source of renewable energy . Some countries have already harnessed the energy of ocean waves, temperature, currents, or tides to power turbines and generate electricity. One source of renewable energy are generators that are powered by tidal streams or ocean currents. They convert the movement of currents into energy. Ocean current generators have not been developed on a large scale, but are working in some places in Ireland and Norway. Some conservationists criticize the impact the large constructions have on the marine environment. Another source of renewable energy is ocean thermal energy conversion (OTEC). It uses the difference in temperature between the warm, surface water and cold, deep water to run an engine. OTEC facilities exist in places with significant differences in ocean depth: Japan, India and the U.S. state of Hawai'i, for instance. An emerging source of renewable energy is salinity gradient power , also known as osmotic power. It is an energy source that uses the power of freshwater entering into saltwater. This technology is still being developed, but it has potential in delta areas where fresh river water is constantly interacting with the ocean. Fishing Fishers catch more than 90 million tons of seafood each year, including more than 100 species of fish and shellfish . Millions of people, from professional fishers to business owners like restaurant owners and boat builders, depend on fisheries for their livelihood . Fishing can be classified in two ways. In subsistence fishing, fishers use their catch to help meet the nutritional needs of their families or communities. In commercial fishing , fishers sell their catch for money, goods or services. Popular subsistence and commercial fish are tuna, cod, and shrimp. Ocean fishing is also a popular recreational sport. Sport fishing can be competitive or noncompetitive. In sport fishing tournaments, individuals or teams compete for prizes based on the size of a particular species caught in a specific time period. Both competitive and noncompetitive sport fishers need licenses to fish, and may or may not keep the caught fish. Increasingly, sport fishers practice catch-and-release fishing, where a fish is caught, measured, weighed, and often recorded on film before being released back to the ocean. Popular game fish (fish caught for sport) are tuna and marlin. Whaling is a type of fishing that involves the harvesting of whales and dolphins. It has declined in popularity since the 19th century but is still a way of life for many cultures, such as those in Scandinavia, Japan, Canada, and the Caribbean. The ocean offers a wealth of fishing and whaling resources, but these resources are threatened. People have harvested so much fish and marine life for food and other products that some species have disappeared. During the 1800s and early 1900s, whalers killed thousands of whales for whale oil (wax made from boiled blubber ) and ivory (whales’ teeth). Some species, including the blue whale ( Balaenoptera musculus ) and the right whale, were hunted nearly to extinction . Many species are still endangered today. In the 1960s and 1970s, catches of important food fish, such as herring in the North Sea and anchovies in the Pacific, began to drop off dramatically. Governments took notice of overfishing —harvesting more fish than the ecosystem can replenish . Fishers were forced to go farther out to sea to find fish, putting them at risk. (Deep-sea fishing is one of the most dangerous jobs in the world.) Now, they use advanced equipment, such as electronic fish finders and large gill nets or trawling nets, to catch more fish. This means there are far fewer fish to reproduce and replenish the supply. In 1992, the collapse, or disappearance, of cod in Canada’s Newfoundland Grand Banks put 40,000 fishers out of work. A ban was placed on cod fishing, and to this day, neither the cod nor the fisheries have recovered. To catch the dwindling numbers of fish, most fishers use trawl nets. They drag the nets along the seabed and across acres of ocean. These nets accidentally catch many small, young fish and mammals. Animals caught in fishing nets meant for other species are called bycatch . The fishing industry and fisheries management agencies argue about how to address the problem of bycatch and overfishing. Those involved in the fishing industry do not want to lose their jobs, while conservationists want to maintain healthy levels of fish in the ocean. A number of consumers are choosing to purchase sustainable seafood . Sustainable seafood is harvested from sources (either wild or farmed) that do not deplete the natural ecosystem. Mining and Drilling Many minerals come from the ocean. Sea salt is a mineral that has been used as a flavoring and preservative since ancient times. Sea salt has many additional minerals, such as calcium, that ordinary table salt lacks. Hydrothermal vents often form seafloor massive sulfide (SMS) deposits , which contain precious metals. These SMS deposits sit on the ocean floor, sometimes in the deep ocean and sometimes closer to the surface. New techniques are being developed to mine the seafloor for valuable minerals such as copper, lead, nickel, gold, and silver. Mining companies employ thousands of people and provide goods and services for millions more. Critics of undersea mining maintain that it disrupts the local ecology . Organisms—corals, shrimp, mussels—that live on the seabed have their habitat disturbed, upsetting the food chain. In addition, destruction of habitat threatens the viability of species that have a narrow niche . Maui’s dolphin ( Cephalorhynchus hectori maui ), for instance, is a critically endangered species native to the waters of New Zealand’s North Island. The numbers of Maui’s dolphin are already reduced because of bycatch. Seabed mining threatens its habitat, putting it at further risk of extinction. Oil is one of the most valuable resources taken from the ocean today. Offshore oil rigs pump petroleum from wells drilled into the continental shelf. About one-quarter of all oil and natural gas supplies now comes from offshore oil deposits around the world. Offshore drilling requires complex engineering . An oil platform can be constructed directly onto the ocean floor, or it can “float” above an anchor. Depending on how far out on the continental shelf an oil platform is located, workers may have to be flown in. Underwater, or subsea, facilities are complicated groups of drilling equipment connected to each other and a single oil rig. Subsea production often requires remotely operated underwater vehicles (ROVs). Some countries invest in offshore drilling for profit and to prevent reliance on oil from other regions. The Gulf of Mexico near the U.S. states of Texas and Louisiana is heavily drilled. Several European countries, including the United Kingdom, Denmark, and the Netherlands, drill in the North Sea. Offshore drilling is a complicated and expensive program, however. There are a limited number of companies that have the knowledge and resources to work with local governments to set up offshore oil rigs. Most of these companies are based in Europe and North America, although they do business all over the world. Some governments have banned offshore oil drilling. They cite safety and environmental concerns. There have been several accidents where the platform itself has exploded, at the cost of many lives. Offshore drilling also poses threats to the ocean ecosystem. Spills and leaks from oil rigs and oil tankers that transport the material seriously harm marine mammals and birds. Oil coats feathers, impairing birds’ ability to maintain their body temperature and remain buoyant in the water. The fur of otters and seals are also coated, and oil entering the digestive tract of animals may damage their organs. Offshore oil rigs also release metal cuttings, minute amounts of oil, and drilling fluid into the ocean every day. Drilling fluid is the liquid used with machinery to drill holes deep in the planet. This liquid can contain pollutants such as toxic chemicals and heavy metals . Pollution Most oil pollution does not come from oil spills, however. It comes from the runoff of pollutants into streams and rivers that flow into the ocean. Most runoff comes from individual consumers. Cars, buses, motorcycles, and even lawn mowers spill oil and grease on roads, streets, and highways. (Runoff is what makes busy roads shiny and sometimes slippery.) Storm drains or creeks wash the runoff into local waterways, which eventually flow into the ocean. The largest U.S. oil spill in the ocean took place in Alaska in 1989, by the tanker Exxon Valdez . The Exxon Valdez spilled at least 10 million gallons of oil into Prince William Sound. In comparison, American and Canadian consumers spill about 16 million gallons of oil runoff into the Atlantic and Pacific Oceans every year. For centuries, people have used the ocean as a dumping ground for sewage and other wastes. In the 21st century, the wastes include not only oil, but also chemical runoff from factories and agriculture . These chemicals include nitrates and phosphates , which are often used as fertilizers . These chemicals encourage algae blooms. An algae bloom is an increase in algae and bacteria that threatens plants and other marine life. Algae blooms limit the amount of oxygen in a marine environment, leading to what are known as dead zones , where little life exists beneath the ocean’s surface. Algae blooms can spread across hundreds or even thousands of miles. Another source of pollution is plastics . Most ocean debris, or garbage, is plastic thrown out by consumers. Plastics such as water bottles, bags, six-pack rings, and packing material put marine life at risk. Sea animals are harmed by the plastic either by getting tangled in it or by eating it. An example of marine pollution consisting mainly of plastics is the Great Pacific Garbage Patch . The Great Pacific Garbage Patch is a floating dump in the North Pacific. It’s about twice the size of Texas and probably contains about 100 million tons of debris. Most of this debris comes from the western coast of North America (the U.S. and Canada) and the eastern coast of Asia (Japan, China, Russia, North Korea, and South Korea). Because of ocean currents and weather patterns, the patch is a relatively stable formation and contains new and disintegrating debris. The smaller pieces of plastic debris are eaten by jellyfish or other organisms, and are then consumed by larger predators in the food web. These plastic chemicals may then enter a human’s diet through fish or shellfish. Another source of pollution is carbon dioxide. The ocean absorbs most carbon dioxide from the atmosphere. Carbon dioxide, which is necessary for life, is known as a greenhouse gas and traps radiation in Earth’s atmosphere. Carbon dioxide forms many acids, called carbonic acids , in the ocean. Ocean ecosystems have adapted to the presence of certain levels of carbonic acids, but the increase in carbon dioxide has led to an increase in ocean acids. This ocean acidification erodes the shells of animals such as clams, crabs, and corals. Global Warming Global warming contributes to rising ocean temperatures and sea levels . Warmer oceans radically alter the ecosystem. Global warming causes cold-water habitats to shrink, meaning there is less room for animals such as penguins, seals, or whales. Plankton, the base of the ocean food chain, thrives in cold water. Warming water means there will be less plankton available for marine life to eat. Melting glaciers and ice sheets contribute to sea level rise . Rising sea levels threaten coastal ecosystems and property. River deltas and estuaries are put at risk for flooding. Coasts are more likely to suffer erosion . Seawater more often contaminates sources of fresh water. All these consequences—flooding, erosion, water contamination—put low-lying island nations, such as the Maldives in the Indian Ocean, at high risk for disaster. To find ways to protect the ocean from pollution and the effects of climate change, scientists from all over the world are cooperating in studies of ocean waters and marine life. They are also working together to control pollution and limit global warming. Many countries are working to reach agreements on how to manage and harvest ocean resources. Although the ocean is vast, it is more easily polluted and damaged than people once thought. It requires care and protection as well as expert management. Only then can it continue to provide the many resources that living things—including people—need.

The Most Coast . . . Canada has 202,080 kilometers (125,567 miles) of coastline. Short But Sweet . . . Monaco has four kilometers (2.5 miles) of coastline.

No, the Toilet Doesn't Flush Backward in Australia The Coriolis effect, which can be seen in large-scale phenomena like trade winds and ocean currents, cannot be duplicated in small basins like sinks.

Extraterrestrial Oceans Mars probably had oceans billions of years ago, but ice and dry seabeds are all that remain today. Europa, one of Jupiter's moons, is probably covered by an ocean of water more than 96 kilometers (60 miles) deep, but it is trapped beneath a layer of ice, which the warmer water below frequently cracks. One of Saturn's moons, Enceladus, has cryovolcanism, or ice volcanoes. Instead of erupting with lava, ice volcanoes erupt with water, ammonia, or methane. Ice volcanoes may indicate oceanic activity.

International Oil Spill The largest oil spill in history, the Gulf War oil spill, released at least 40 million gallons of oil into the Persian Gulf. Valves at the Sea Island oil terminal in Kuwait were opened on purpose after Iraq invaded Kuwait in 1991. The oil was intended to stop a landing by U.S. Marines, but the oil drifted south to the shores of Saudi Arabia. A study of the Gulf War oil spill (conducted by the United Nations, several countries in the Middle East and the United States) found that most of the spilled oil evaporated and caused little damage to the environment.

Ocean Seas The floors of the Caspian Sea and the Black Sea are more like the ocean than other seas they do not rest on a continent, but directly on the ocean's basalt crust.

Early Ocean Explorers Polynesian people navigated a region of the Pacific Ocean now known as the Polynesian Triangle by 700 C.E. The corners of the Polynesian Triangle are islands: the American state of Hawai'i, the country of New Zealand, and the Chilean territory of Easter Island (also known as Rapa Nui). The distance between Easter Island and New Zealand, the longest length of the Polynesian Triangle, is one-quarter of Earth's circumference, more than 10,000 kilometers (6,200 miles). Polynesians successfully traveled these distances in canoes. It would be hundreds of years before another culture explored the ocean to this extent.

Media Credits

The audio, illustrations, photos, and videos are credited beneath the media asset, except for promotional images, which generally link to another page that contains the media credit. The Rights Holder for media is the person or group credited.

Illustrators

Educator reviewer, expert reviewer, last updated.

March 5, 2024

User Permissions

For information on user permissions, please read our Terms of Service. If you have questions about how to cite anything on our website in your project or classroom presentation, please contact your teacher. They will best know the preferred format. When you reach out to them, you will need the page title, URL, and the date you accessed the resource.

If a media asset is downloadable, a download button appears in the corner of the media viewer. If no button appears, you cannot download or save the media.

Text on this page is printable and can be used according to our Terms of Service .

Interactives

Any interactives on this page can only be played while you are visiting our website. You cannot download interactives.

Related Resources

Undersea: Rachel Carson’s Lyrical and Revolutionary 1937 Masterpiece Inviting Humans to Explore Earth from the Perspective of Other Creatures

By maria popova.

Pioneering biologist and writer Rachel Carson (May 27, 1907–April 14, 1964) catalyzed the modern environmental movement with the groundbreaking publication of Silent Spring in 1962, but the spark for this slow-burning revolution was kindled a quarter century earlier, while 28-year-old Carson was working for what would later become the U.S. Fish and Wildlife Service. When she was tasked with writing a brochure for the Fisheries Bureau, summarizing their annual research findings, Carson transmuted the science into poetry and turned in something so exquisitely lyrical that her supervisor told her they simply couldn’t publish it as their standard government report. But he encouraged her to submit it to The Atlantic Monthly as an essay. She did. It was enthusiastically accepted and published in the September 1937 issue as the trailblazing masterpiece “Undersea” under the byline R.L. Carson — a choice reflective of Carson’s era-calibrated fear that her writing wouldn’t be taken as seriously if her gender was known. Ironically, of the twenty-one contributors in that issue of the magazine, Carson’s name is the only one widely recognized today.

The essay became the backbone of Carson’s first book, Under the Sea-Wind , which remained her favorite piece of writing, and was later included in the excellent Lost Woods: The Discovered Writing of Rachel Carson ( public library ).

Creatively, “Undersea” was unlike anything ever published before — Carson brought a strong literary aesthetic to science, which over the next two decades would establish her as the most celebrated science writer of her time. Conceptually, it accomplished something even Darwin hadn’t — it invited the reader to step beyond our reflexive human hubris and empathically explore this Pale Blue Dot from the vantage point of the innumerable other creatures with which we share it. Decades before philosopher Thomas Nagel wrote his iconic essay “What Is it Like to Be a Bat?” and nearly a century before Sy Montgomery’s beautiful inquiry into the soul of an octopus , Carson considered the experience of other consciousnesses. What the nature writer Henry Beston , one of Carson’s great heroes, brought to the land, she brought first to the sea, then to all of Earth — intensely lyrical prose undergirded by a lively reverence for nature and a sympathetic curiosity about the reality of other living beings.

Long before scientists like pioneering oceanographer Sylvia “Her Deepness” Earle plunged into the depths of the ocean, Carson shepherds the human imagination to the mysterious wonderland thriving below the surface of the seas that envelop Earth:

Who has known the ocean? Neither you nor I, with our earth-bound senses, know the foam and surge of the tide that beats over the crab hiding under the seaweed of his tide-pool home; or the lilt of the long, slow swells of mid-ocean, where shoals of wandering fish prey and are preyed upon, and the dolphin breaks the waves to breathe the upper atmosphere. Nor can we know the vicissitudes of life on the ocean floor, where sunlight, filtering through a hundred feet of water, makes but a fleeting, bluish twilight, in which dwell sponge and mollusk and starfish and coral, where swarms of diminutive fish twinkle through the dusk like a silver rain of meteors, and eels lie in wait among the rocks. Even less is it given to man to descend those six incomprehensible miles into the recesses of the abyss, where reign utter silence and unvarying cold and eternal night. To sense this world of waters known to the creatures of the sea we must shed our human perceptions of length and breadth and time and place, and enter vicariously into a universe of all-pervading water.

After a tour of some of the ocean’s most unusual and dazzling creatures, Carson considers the glorious and inevitable interconnectedness of the natural world, no different from the “inescapable network of mutuality” which Martin Luther King so passionately championed in the human world. She writes:

The ocean is a place of paradoxes. It is the home of the great white shark, two thousand pound killer of the seas. And of the hundred foot blue whale, the largest animal that ever lived. It is also the home of living things so small that your two hands may scoop up as many of them as there are stars in the Milky Way. And it is becoming of the flowering of astronomical numbers of these diminutive plants known as diatoms, that the surface waters of the ocean are in reality boundless pastures. Every marine animal, from the smallest to the sharks and whales is ultimately dependent for its food upon these microscopic entities of the vegetable life of the ocean. Within their fragile walls, the sea performs a vital alchemy that utilizes the sterile chemical elements dissolved in the water and welds them with the torch of sunlight into the stuff of life. Only through the little-understood synthesis of proteins, fats and carbohydrates by myriad plant “producers” is the mineral wealth of the sea made available to the animal “consumers” that browse as they float with the currents. Drifting endlessly, midway between the sea of air above and the depths of the abyss below, these strange creatures and the marine inflorescence that sustains them are called “plankton” — the wanderers.

Carson continues her marine expedition farther and deeper into the ocean, to return in the final paragraphs to this central interconnectedness of life — perhaps, she poetically suggests, our only real taste of immortality:

While bottoms near the shore are covered with detritus from the land, the remains of the floating and swimming creatures of the sea prevail in the deep waters of the open ocean. Beneath the tropical seas, in depths of 1000 to 1500 fathoms, calcareous oozes cover nearly a third of the ocean floor; while the colder waters of the temperate and polar regions release to the underlying bottom the silicious remains of diatoms and Radiolaria. In the red clay that carpets the great deeps at 5000 fathoms or more, such delicate skeletons are extremely rare. Among the few organic remains not dissolved before they reach these cold and silent depths are the ear bones of whales and the teeth of sharks. Thus we see parts of the plan fall into place: the water receiving from earth and air the simple materials, storing them up into the gathering energy of the spring wakens the sleeping plants to a burst of dynamic energy, hungry swarms of planktonic animals growing and multiplying upon the abundant plants, and themselves falling prey to the shoals of fish; all, in the end; to be redissolved into their component substances when the inexorable laws of the sea demand it. Individual elements are lost to view, only to repair again and again in different incarnations in a kind material immortality. Kindred forces to those which, in some period inconceivably remote, gave birth to that primeval bit of protoplasm tossing on the ancient seas continue their mighty and incomprehensible work. Against this cosmic background the lifespan of a particular plant or animal appears, not as drama complete in itself, but only as a brief interlude in a panorama of endless change.

Complement the altogether fantastic Lost Woods with Carson courageous and prescient 1953 protest against the government’s assault on science and nature , the story of how she awakened the modern environmental conscience , and her touching farewell to her beloved , then revisit these gorgeous illustrations of sea creatures from Indian folklore and Susan Middleton’s mesmerizing photographs of marine invertebrates .

UPDATE: For more on Carson, her epoch-making cultural contribution, and her unusual private life, she is the crowning figure in my book Figuring .

— Published February 28, 2017 — https://www.themarginalian.org/2017/02/28/undersea-rachel-carson/ —

www.themarginalian.org

PRINT ARTICLE

Email article, filed under, books culture rachel carson science, view full site.

The Marginalian participates in the Bookshop.org and Amazon.com affiliate programs, designed to provide a means for sites to earn commissions by linking to books. In more human terms, this means that whenever you buy a book from a link here, I receive a small percentage of its price, which goes straight back into my own colossal biblioexpenses. Privacy policy . (TLDR: You're safe — there are no nefarious "third parties" lurking on my watch or shedding crumbs of the "cookies" the rest of the internet uses.)

Under the Sea: Books about Ocean Life for All Ages

These books about ocean life are deep, thought-provoking texts about our oceans, sea creatures, and humans' impact on marine ecosystems.

Ashley Holstrom

Ashley Holstrom helps make books at Sourcebooks. She lives near Chicago with her cat named after Hemingway and her bookshelves organized by color. Newsletter: Crooked Reads . Twitter: @alholstrom .

View All posts by Ashley Holstrom

As far back as I can remember, I’ve been fascinated by ocean life, but always from a distance. I have a distinct memory, though I don’t even know if it’s real, of my dad and I channel surfing and landing on a show about whales or coral reefs or something. As a kid, I imagined the ceiling fan in my bedroom was an octopus. In high school, my best friend and I regularly wandered around exotic pet stores admiring all the colorful fish in their tanks. My first pet was a goldfish named Flash. I screamed every time I had to take him out of the bowl to clean it. 

The problem: I’m petrified of deep water. So my only fix for a curiosity about majestic sea creatures is through nature documentaries and books about ocean life. That’s fine by me, because in the last few years, a slew of incredible, unique books on the subject have been published. 

These books about ocean life aren’t textbooks showcasing each species under the sea. They’re deep, thought-provoking texts about how some of the world’s greatest creatures are still mysteries to us, how humans are interrupting their communication, and how climate change and pollution are ruining their homes. These books are written by people who have devoted their lives to studying — and saving — the ocean. 

Books About Ocean Life for Adults

How Far the Light Reaches: A Life in Ten Sea Creatures by Sabrina Imbler (Little, Brown and Company, December 6)

Sabrina Imbler has always been enraptured by the allure of sea creatures, from the time they protested the sale of goldfish at a pet store to the years spent studying a variety of life. Each essay profiles a different creature — the deep ocean octopus who starved herself watching over her eggs, the Chinese sturgeon who smash into the dams that block their migration route — as Imbler tells an intimate story about their life as a queer, mixed race science writer. How Far the Light Reaches is a truly unique collection of essays about ocean life as it pertains to the author’s own story.

How to Speak Whale: A Voyage into the Future of Animal Communication by Tom Mustill

When a 30-ton humpback whale breached and landed on top of Tom Mustill’s kayak, he was inspired to study interactions between humans and whales. They can’t all be as dramatic as his, but the connections are still fascinating. He meets two tech entrepreneurs who use artificial intelligence to analyze and decode animal language, eavesdropping on the world’s largest mammals. How to Speak Whale goes beyond the use of technology in understanding whale communication, though. Mustill dives into the history of the whaling industry and looks beyond, questioning if human–whale communication could actually be harmful.

Thank you for signing up! Keep an eye on your inbox. By signing up you agree to our terms of use

Fathoms: The World in the Whale by Rebecca Giggs

Fathoms explores changes in ecology through the lives of whales. After spotting a humpback whale stranded on her local beachfront, Rebecca Giggs was curious to find out what it meant about the condition of the ocean. The book melds together history, philosophy, and science to figure out how whales experience ecological change, especially in a time of technological advances and devastating pollution. She also shares the magic and mystique of these beasts, from beautiful whale songs to rare whales that haven’t even been named yet.

Spineless: The Science of Jellyfish and the Art of Growing a Backbone by Juli Berwald

Juli Berwald left her career in ocean science to raise a family, but a decade later was drawn back in by jellyfish. They’d been clogging power plants and decimating fisheries, and she wanted to figure out what was causing the jellyfish population explosion. Spineless is the fruit of that journey across the globe, meeting biologists who are devoted to jellyfish and even raising jellyfish in her own dining room.

The Book of Eels: Our Enduring Fascination with the Most Mysterious Creature in the Natural World by Patrik Svensson, translated by Agnes Broomé

What do we know about eels? Very little! No one knows where they come from or what they are, really — fish? snakes? How do they reproduce? Patrik Svensson looks at these questions and more through research, literature, history, marine biology, and his own experience fishing for eels with his father. The Book of Eels is a gorgeous blend of memoir and nature writing, with the eel mystery becoming a vessel for understanding the human condition.

Emperors of the Deep: Sharks — The Ocean’s Most Mysterious, Most Misunderstood, and Most Important Guardians by William McKeever

William McKeever, documentarian and conservationist, wants to reset the record on how our society views sharks, because it’s not all the drama and horror of Jaws and Shark Week . Emperors of the Deep focuses on four species — mako, tiger, hammerhead, and, of course, the great white — and shares fascinating facts, like how sharks are 50 million years older than trees and have survived five extinction-level events. The most devastating truth of all: sharks account for a mere six human fatalities per year, but humans kill 100 million sharks per year.

Books About Ocean Life for Kids

Sharks (A Day in the Life): What Do Great Whites, Hammerheads, and Whale Sharks Get Up To All Day? by Carlee Jackson, illustrated by Chaaya Prabhat

If you’ve ever wondered what a shark does all day, Carlee Jackson has the answer. The marine biologist and shark conservationist brings us on a journey through the ocean, where a great white shark escapes a pod of orcas and a nurse shark sleeps in a coral reef, all the while dropping little animal facts. Chaaya Prabhat’s gorgeous and colorful illustrations make this picture book about ocean life an unforgettable one.

Mother of Sharks by Melissa Cristina Márquez, illustrated by Devin Elle Kurtz (Penguin Workshop, May 2023)

Mother of Sharks is a beautiful picture book melding science and fantasy to tell the author’s origin story. Melissa Cristina Márquez, a shark scientist, loved the ocean more than anything when she was a kid. She never wanted to leave the beach near her home in Puerto Rico, and in this story, she meets a crab who takes her on a dreamy adventure through the ocean to teach her the truth about sharks. Devin Elle Kurtz’s illustrations add beauty to this fantastical tale about marine conservation.

If you’re looking for more like this, check out these ocean books for kids and books about whales . Alternatively, scare yourself with some horror books about the ocean .

You Might Also Like

Essay on Sea

Students are often asked to write an essay on Sea in their schools and colleges. And if you’re also looking for the same, we have created 100-word, 250-word, and 500-word essays on the topic.

Let’s take a look…

100 Words Essay on Sea

The magnificent sea.

The sea, a vast body of saltwater, covers 71% of our planet’s surface. Its depth varies, creating a diverse habitat for countless marine species.

Life in the Sea

The sea teems with life, from the smallest plankton to the largest whales. It’s a vibrant ecosystem, providing food and shelter to all marine life.

Importance of the Sea

The sea plays a crucial role in maintaining Earth’s climate. It absorbs heat, helping to regulate temperatures. Additionally, it generates oxygen, contributing to the air we breathe.

Threats to the Sea

Sadly, human activities like pollution and overfishing pose threats to the sea, endangering its delicate balance. We must strive to protect it.

250 Words Essay on Sea

The sea: a vast universe.

The sea, an immense expanse of saline water, covers approximately 71% of the Earth’s surface, serving as a testament to the planet’s life-sustaining capabilities. Encapsulating a world teeming with diverse life forms and ecosystems, the sea is a vital part of our planet’s biosphere.

The Sea’s Biodiversity

The sea is a cradle of biodiversity, hosting an array of organisms that range from the microscopic plankton to the colossal blue whale. Coral reefs, often referred to as the ‘rainforests of the sea’, are particularly rich in species diversity. These complex ecosystems not only provide shelter and food for numerous marine species but also play a critical role in carbon sequestration, aiding in the fight against climate change.

Sea as a Resource

The sea is a critical resource for humans, providing food, minerals, and energy. Fisheries and aquaculture are significant contributors to global food security, while offshore drilling and wind farms harness the sea’s potential as an energy source. Moreover, the sea acts as a major conduit for international trade, with countless vessels traversing its waters daily.

However, the sea faces numerous threats, primarily from human activities. Overfishing, pollution, and climate change-induced warming and acidification are causing unprecedented changes to marine ecosystems. These threats, if left unchecked, could lead to a significant loss of biodiversity and the collapse of vital ecosystem services.

In conclusion, the sea is an integral part of our planet, teeming with life and providing invaluable resources. Its preservation is not just a moral imperative but a necessity for our survival.

500 Words Essay on Sea

The sea: a deep dive into its significance, the sea as a biodiversity hotspot.

The sea is home to an estimated 230,000 known species, but the actual number may be in the millions. This biodiversity spans from microscopic phytoplankton, which contribute up to 50% of the Earth’s oxygen, to the largest animal ever to have lived, the blue whale. Coral reefs, often referred to as the ‘rainforests of the sea,’ are particularly rich in species diversity. However, the sea’s biodiversity is under threat due to human activities such as overfishing, pollution, and climate change, which can lead to habitat destruction and species extinction.

The Sea and Climate

The sea plays a crucial role in regulating the Earth’s climate. It absorbs about a quarter of the carbon dioxide humans produce, reducing the impact of greenhouse gases. The sea’s surface also absorbs the majority of the sun’s radiation, leading to the evaporation of water and the formation of clouds. This process, along with the sea’s currents, helps distribute heat around the globe, influencing weather and climate patterns.

The Sea and Human Culture

The sea and economy.

The sea is a significant contributor to the global economy. It provides a wealth of resources, including fish, shellfish, and seaweed, which are vital sources of food and income for millions of people. The sea also facilitates international trade, with about 80% of global trade by volume being carried by sea. Moreover, the sea is a major destination for tourism and recreation, contributing billions to the economy.

The Sea: A Call for Conservation

Despite its importance, the sea is facing unprecedented threats due to human activities. Overfishing is depleting fish stocks, pollution is causing harm to marine life, and climate change is leading to ocean warming and acidification. These issues underscore the urgent need for marine conservation. Through sustainable practices and international cooperation, we can help protect the sea and ensure its health for future generations.

That’s it! I hope the essay helped you.

Apart from these, you can look at all the essays by clicking here .

Happy studying!

Leave a Reply Cancel reply

• Voter Guide
• Michigan Politics
• John Carlisle
• M.L. Elrick
• Observer & Eccentric

Marcellus Williams' Missouri execution to go forward despite prosecutor's concerns

A Missouri judge denied a motion to vacate a condemned man's death sentence despite attorneys, including one prosecutor, saying evidence was mishandled in the 1998 trial that could have exonerated Marcellus “Khaliifah” William.

William, 55, remains scheduled to die by lethal injection Sept. 24 at  Potosi Correctional Center  in Mineral Point, about 70 miles southwest of St. Louis.

Williams was convicted of first-degree murder for the slaying of 42-year-old Lisha Gayle, a former reporter for the St. Louis Post-Dispatch. A social worker at the time, the woman was found slain in the suburban St. Louis home she shared with husband.

She was stabbed 43 times with a kitchen knife taken from inside the couple's home, court papers show.

St. Louis County Circuit Judge Bruce Hilton 's Thursday ruling stemmed from an Aug. 28 evidentiary hearing during which St. Louis County prosecutor Attorney Wesley Bell presented a new DNA lab report showing the murder weapon had been mishandled during Williams' trial.

Bell had filed a motion based on new DNA testing conducted on murder weapon collected at the crime scene, which the prosecutors said "conclusively excluded" Williams as the person who killed Gayle.

Hilton ruled that vacating the 2001 conviction was not warranted under Missouri law, according to court records.

Tricia Rojo Bushnell, one of Williams' attorneys, told USA TODAY her client's defense team will file more appeals and seek clemency from Republican Gov. Mike Parson.

“The decision of a prosecutor to move to vacate a murder conviction and death sentence is not done lightly," Bushnell said Thursday. "There is overwhelming evidence that Marcellus Williams’ trial was constitutionally unfair, including revelations that the state contaminated the most critical evidence in the case − the murder weapon."

“We will continue pursuing every possible option to prevent Mr. Williams’ wrongful execution," Bushnell said. "There is still time for the courts or Governor Parson to ensure that Missouri does not commit the irreparable injustice of executing an innocent person.”

Death penalty in the US: Which states still execute inmates, who has executed the most?

What did William's attorneys argue about the case?

The crux of Williams' argument focused on DNA evidence that authorities recently determined was contaminated during the trial by two officials in the St. Louis Prosecuting Attorney's Office office − a retired prosecutor and an investigator.

During the evidentiary hearing late last month, prosecutor Keith Larner admitted to handling the murder weapon five times before the trial without gloves, indicating Williams could be innocent.

Although Bell moved to overturn Williams' murder conviction, State Attorney General Andrew Bailey argued it should stand.

Florida executes 1st 2024 prisoner: Loran Cole executed in murder of Florida State University student whose sister was raped

Court papers: Williams' DNA was not on the murder weapon

Earlier this year, it appeared Williams’ conviction could be overturned when Bell, the prosecutor, filed a motion to vacate the condemned prisoners sentence, citing testing determining that Williams’ DNA was not on the murder weapon. That testing was not available when Williams was tried in 2001.

"New evidence significantly undermines confidence in the soundness of Mr. Williams’s conviction," Bell wrote in the 86-page petition filed Jan. 26. "Mr. Williams may be innocent."

Additional testing determined the murder weapon had been so mishandled by the prosecutor's office it would be impossible to identify the killer.

On Aug. 21, Bell's office and Williams' attorneys reached an agreement that Williams would enter a new, no-contest plea to first-degree murder in exchange for life in prison sentence without parole. The victim's husband, Dr. Daniel Picus, signed off on the plea.

But on the same day Hilton accepted the plea, the state's Attorney General intervened and filed a motion arguing that Williams' death sentence should still stand. The defense, Bailey said, "created a false narrative of innocence in order to get a convicted murderer off of death row and fulfill their political ends."

The Missouri Supreme Court then blocked an agreement to spare Williams' life.

The mishandling “destroyed his last and best chance” to prove his innocence, Jonathan Potts, one of Williams defense attorneys, told the judge during his closing argument at the Aug. 28 evidentiary hearing.

"It is in the interest of every Missourian that the rule of law is fought for and upheld – every time, without fail," Bailey said in a statement the following day. "I am glad the Missouri Supreme Court recognized that."

A political battle over a man's life

Bell, a Democrat, was thrust into the spotlight following the police fatal shooting of Michael Brown in Ferguson, Missouri, 10 years ago. Bell is now also a Democratic candidate for U.S. Congress after defeating incumbent U.S. Rep. Cori Bush  in a primary race last month.

Bailey, a Republican, has previously opposed wrongful conviction claims , most recently fighting an order by a St. Louis Circuit Court judge to release a man whose murder conviction was overturned in July. But on July 30, just over a week after the high court intervened,  Christopher Dunn , 52,  was released from prison after over 30 years behind bars.

Under a new Missouri law , prosecutors may challenge past convictions if they believe a person was imprisoned for crimes they didn’t commit. Since the law went into effect in 2021, only two other people have been released from custody after years in prison:  Lamar Johnson and Kevin Strickland.

Potts said Williams' case marked the first time it was used for someone on death row.

Williams was nearly executed once before, but spared hours before his August 2017 scheduled lethal injection.

At the time, then-Republican Gov. Eric Greitens, granted a stay after testing showed DNA on the weapon matched an unknown person.

The findings prompted Bell to reexamine the case.

What has Williams argued in his murder case?

Gayle's husband was cleared of the killing. Physical evidence at the scene, court documents show, never tied him to the crime.

The case relied on testimony of two witnesses, including a jailhouse informant who testified in exchange for a reduced sentence, reported the Springfield News-Leader, part of the USA TODAY Network.

The other witness was Williams' ex-girlfriend, a convicted felon with a history of drug abuse, who court records show led police to his trunk and found the victim's laptop a year after the crime took place.

Williams, court documents go onto say, said his ex gave him the laptop because she wanted a $10,000 reward being offered to solve Gayle's homicide case.

Testing revealed Williams' DNA was never found on the knife found in Gayle's neck.

"Bloody shoeprints were present near a knife sheath in the kitchen, in the hallway leading to the front foyer, and on the rug near Ms. Gayle’s body. Bloody fingerprints were found along the wall. And hairs believed to belong to the perpetrator were collected from Ms. Gayle’s t-shirt, her hands, and the floor" Bell wrote in his motion to vacate Williams' sentence. "None of this physical evidence tied Mr. Williams to Ms. Gayle’s murder."

If his lethal injection goes forward, Williams will become the third inmate executed in Missouri this year.

Natalie Neysa Alund is a senior reporter for USA TODAY. Reach her at [email protected] and follow her on X @nataliealund.