While the Earth's oceans are known as five separate entities, there is really only one ocean. So, how big is it? As of 2013, it takes up 71% of the Earth, houses 99% of the biosphere, and contains some of Earth's grandest geological features. Scott Gass reminds us of the influence humans have on the ocean and the influence it has on us. [Directe...

In the deepest, darkest parts of the oceans are ecosystems with more diversity than a tropical rainforest. Taking us on a voyage into the ocean -- from the deepest trenches to the remains of Titanic -- marine biologist David Gallo explores the wonder and beauty of marine life.

As we keep pumping carbon dioxide into the atmosphere, more of it is dissolving in the oceans, leading to drastic changes in the water's chemistry. Triona McGrath researches this process, known as ocean acidification, and in this talk she takes us for a dive into an oceanographer's world. Learn more about how the "evil twin of climate change" is...

Pushing his body through epic cold-water swims, Lewis Gordon Pugh wants to draw attention to our global climate. He's just back from swimming in a meltwater lake on the slopes of Mount Everest.

Rob Dunbar hunts for data on our climate from 12,000 years ago, finding clues inside ancient seabeds and corals and inside ice sheets. His work is vital in setting baselines for fixing our current climate -- and in tracking the rise of deadly ocean acidification.

Heidi M. Sosik is an ocean scientist who uses tools like lasers and robotic cameras to figure out how tiny organisms in the ocean affect our whole planet.

A conservationist and former diplomat, Susan Ruffo is the senior advisor for Ocean and Climate at United Nations Foundation.

Barbara Block studies how tuna, billfish and sharks move around (and stay warm) in the open ocean. Knowing how these large predators travel through pelagic waters will help us understand their role in the wider ocean ecosystem.

Tierney Thys is a marine biologist and science educator. She studies the behavior of the Mola mola, or giant ocean sunfish -- and works with other scientists to make films that share the wonders they see.

Island and coastal nations need to protect their waters to keep the oceans healthy. But they often have lots of debt and aren't able to prioritize ocean conservation over other needs. The team at The Nature Conservancy sees a way to solve both problems at once: restructuring a nation's debt in exchange for its government's commitment to protect ...

Rob Dunbar looks deeply at ancient corals and sediments to study how the climate and the oceans have shifted over the past 50 to 12,000 years -- and how the Antarctic ecosystem is changing right now.

Dr. Laura Robinson's scientific mission is to document and understand the processes that govern climate.

What's a marine biologist doing talking about world hunger? Well, says Jackie Savitz, fixing the world's oceans might just help to feed the planet's billion hungriest people. In an eye-opening talk, Savitz tells us what’s really going on in our global fisheries right now — it’s not good — and offers smart suggestions of how we can help them heal...

Stephen Palumbi studies the way humanity and ocean life interact and intertwine. His insights into our codependence offer ideas for protecting both the ocean and ourselves.

Susan Shaw is an internationally recognized marine toxicologist, author and explorer.

Barton Seaver is an advocate of sustainable seafood and a chef in Washington DC. His work tells the story of our common resources through the communion we all share – dinner.

The ocean is a naturally noisy place full of singing whales, grunting fish, snapping shrimp, cracking ice, wind and rain. But human-made sounds -- from ship engines to oil drilling -- have become an acute threat to marine life, says science journalist Nicola Jones. Watch (and listen) as she discusses the strange things that happen to underwater ...

Angelicque White investigates changes happening in the ocean through the very smallest lens.

As a diver in the 1970s, marine ecologist Enric Sala saw once-lush oceanscapes reduced to underwater deserts -- but later, in marine preserves across the globe, he also witnessed the ocean's power to rejuvenate itself when left to its own natural devices. Could rewilding the planet help us restore biodiversity and reduce the impacts of climate c...

New videography techniques have opened up the oceans' microscopic ecosystem, revealing it to be both mesmerizingly beautiful and astoundingly complex. Marine biologist Tierney Thys teamed with Christian Sardet (CNRS/Tara Oceans), Noé Sardet and Sharif Mirshak to use footage from the Plankton Chronicles project to create a film designed to ignite...

Chef Barton Seaver presents a modern dilemma: Seafood is one of our healthier protein options, but overfishing is desperately harming our oceans. He suggests a simple way to keep fish on the dinner table that includes every mom's favorite adage -- "Eat your vegetables!"

Paul Greenberg researches and writes about fish, aquaculture and the future of the ocean.

Charles Moore is founder of the Algalita Marine Research Foundation. He captains the foundation's research vessel, the Alguita, documenting the great expanses of plastic waste that now litter our oceans.

Carl Safina's writing explores the scientific, moral and social dimensions of our relationship with nature.

Jackson Browne plays a song about being on the ocean ... or really, being anywhere among passionate friends. (He started writing this song aboard Mission Blue Voyage, a Sylvia Earle-inspired conference about saving the ocean.) "If I could be anywhere," he sings, "anywhere right now, I would be here."

With just one breath, Guillaume Néry can dive to -125m below the water's surface.

Penny Chisholm studies an extremely tiny microorganism that plays an enormous role in ocean ecosystems. Discovered only three decades ago, it has defined her career and inspired her to think differently about life on Earth.

David Lang is the cofounder and CEO of OpenROV, designing and manufacturing underwater drones.

TED Senior Fellow Cesar Harada aims to harness the forces of nature as he invents innovative remedies for man-made problems like oil spills and radioactive leaks.

Edith Widder combines her expertise in research and technological innovation with a commitment to stopping and reversing the degradation of our marine environment.