There is one place on Earth where the impacts of climate change are most profound and yet practically invisible: the oceans. As global emissions soar, the oceans are becoming warmer and more acidic, creating unbearable living conditions for all marine life and threatening precious ecosystems. Joshua Jackson travels to Australia’s Great Barrier Reef to look at the devastating impacts of ocean warming on the world’s largest reef system and the predicted impact of ocean acidification. In the Philippines, he looks at the impact of climate change in a place where hundreds of millions of people rely on healthy reefs for food, income and protection from storms. Oceans, which cover 70 percent of the world, are crucial to our species’ survival. What will happen if our life-support system is disrupted? Without healthy oceans, we have everything to lose.