. >> kimokeo takes me on a traditional outrigger canoe, for one final visit to an area known as the coralemetery. this is what becomes of coral when it has died, and its remaining skeleton becomes brittle and collapses. >> when i think of a coral reef i think of an ecosystem that's full of life, colorful and structured, almost cathedral-like, but i have to say i'm a little heart broken right now because where i'm standing right now is indicative of what might happen to corals if the threats go uncontrolled, they'll probably look more and more like this. >> from the rainforest of the seas to a lifeless pile of rubble. and without change, it is a fate that could befall the world's coral reefs within most of our lifetimes. >> i've never seen coral bleaching like this, i've never seen this happening, where you see entire mounds of coral that are just completely on the verge of death. >> how does that make you feel? >> i'm sad, you know, it made me actually really really sad to go through there because i think of a coral reef as this iconic system. for me it was almost a spiritual experience t