Huffington Post: Sometimes, when things aren't quite right with the oceans, a once-pristine, colorful reef will start to die. Corals that take thousands of years to grow, polyp-by-tiny-polyp, get a little finicky when it comes to temperature or chemical changes in the water. And in the span of just a few months, an underwater rainbow can turn a bright, ghostly white. What's striking when you see the photos is how unnatural it all seems. The phenomenon goes by the dreaded name of bleaching. It's happening now around...