The first coral-bleaching event to whiten reefs worldwide happened in 1998, an El Niño year. Some 16 percent of the planet’s reefs died. In 2010, El Niño brought another. Now NOAA says we’re in the midst of the third ever such event that has dire implications for biodiversity, fisheries, and the overall health of our oceans.
This time, the XL Catlin Seaview Survey was ready. The team started taking panoramic photographs of reefs in 2012 to create a visual record of the change over time. Acting on NOAA’s dire predictions for this year, they captured images of the event unfolding.
Ocean warming from climate change, exacerbated by El Niño’s unusually high temperatures, makes the marine invertebrates eject the symbiotic algae living in their tissues, which they depend on for nutrition (and their vibrant color). Corals don’t always after die after bleaching, but the current whiteout started in 2014, and a continuing El Niño could drag the phenomenon out to 2016. That degree of prolonged stress has scientists seriously worried.
Corals just didn’t evolve to live in a hot tub.
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