"In the Wake of the Exxon Valdez."

Marine botanist Sylvia Earle. She's been described as one of the most intrepid divers in the history of underwater exploration. She's swum with humpback whales, explored the kelp forests off the coast of California, and dove into the trenches off the coasts of Hawaii where she once went to depths of 1,250 feet, which at the time was the deepest any human had dove without a connection to the surface.

Journalist Chloe Sorvino says the meat industry pollutes the environment, contributes to climate change and leaves the meat supply chain vulnerable to major disruptions.

New York Times science writer David Wallace-Wells says the cost of solar and wind energy has fallen dramatically. Nevertheless, we're still facing painful, long-lasting changes to the planet.