“Coral in the Florida Keys, home to the largest reef in the continental US, is dying. The ghostly white appearance of the coral above is due to a phenomenon known as bleaching. Coral, an anemone-like marine animal, gets most of its color and food from a kind of algae that lives within its tissue. When that algae disappears, the coral appears stark white. Bleached corals aren’t dead; they are starving to death.
What happened between those two snapshots is extreme and unrelenting heat. Since July, a record-setting heat wave has been cooking waters in Florida and parts of the Caribbean, at times pushing water temperatures above 100 degrees. This excessive heat causes the relationship between coral and those symbiotic algae to break down; the algae leave the coral, though it’s not entirely clear which initiates the breakup.
The result of this epic marine heat wave is a devastating bleaching event that stretches across the Keys and much of the Caribbean, threatening the future of the region’s coral reefs. That in turn threatens human lives and well-being. These ecosystems — which were already under siege well before this summer — protect coastal communities from storm surge, support fisheries, and drive tourism.”
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“Underwater photojournalist Jennifer Adler and I went scuba-diving in the Florida Keys before and after this marine heat wave. What we saw is a stark reminder that climate change is not a distant threat; it’s destroying ecosystems today.”
https://www.vox.com/climate/23879347/florida-keys-coral-reef-photos-climate-change