In early June 2023, the coral reefs in the lower Florida Keys and the Dry Tortugas were stunning. We were in diving gear, checking up on hundreds of corals we had transplanted as part of our experiments. The corals’ classic orange-brown colors showed they were thriving.
Just three weeks later, we got a call – a marine heat wave was building, and water temperatures on the reef were dangerously high. Our transplanted corals were bleaching under the heat stress, turning bone white. Some were already dead.
