Tuna are ocean athletes -- fast, far-ranging predators whose habits we're just beginning to understand. Marine biologist Barbara Block fits tuna with tracking tags (complete with transponders) that record unprecedented amounts of data about these gorgeous, threatened fish and the ocean habitats they move through.

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.

What's link between the ocean's health and our health? Marine biologist Stephen Palumbi shows how toxins at the bottom of the ocean food chain find their way into our bodies -- and tells a shocking story of toxic contamination in the fish market, where consumers were being tricked into buying fish that's not only mislabeled but unsafe.

Oceanographer John Delaney is leading the team that is building an underwater network of high-def cameras and sensors that will turn our ocean into a global interactive lab -- sparking an explosion of rich data about the world below.

In this bracing talk, coral reef ecologist Jeremy Jackson lays out the shocking state of the ocean today: overfished, overheated, polluted, with indicators that things will get much worse. Astonishing photos and stats make the case.

Peter Tyack of Woods Hole talks about a hidden wonder of the sea: underwater sound. Onstage at Mission Blue, he explains the amazing ways whales use sound and song to communicate across hundreds of miles of ocean.

The wish Mission Blue The winner Sylvia Earle The year 2009

Enric Sala shares glorious images -- and surprising insights and data -- from some of the most pristine areas of the ocean. He shows how we can restore more of our oceans to this healthy, balanced state, and the powerful ecological and economic benefits of doing so.

Think of penguins as ocean sentinels, says Dee Boersma -- they're on the frontlines of sea change. Sharing stories of penguin life and culture, she suggests that we start listening to what penguins are telling us.

Photographer Brian Skerry shoots life above and below the waves -- as he puts it, both the horror and the magic of the ocean. Sharing amazing, intimate shots of undersea creatures, he shows how powerful images can help make change.

Mission Blue II: Papua New Guinea to Solomon Islands October 10 - October 16, 2015

Some 80 to 90 percent of undersea creatures make light -- and we know very little about how or why. Bioluminescence expert Edith Widder explores this glowing, sparkling, luminous world, sharing glorious images and insight into the unseen depths (and brights) of the ocean.