Coral reefs throughout U.S. ocean regions are ailing and dying, according to NOAA surveyors who say that “bleaching” is taking a severe toll on coral in Hawaii, Florida, Guam, and Puerto Rico. They expect all of these areas’ coral to be wiped out by 2050 at the latest, absent major action to curb climate change.
“The idea we will sustain reefs in the US 100 years from now is pure imagination. At the current rate it will be just 20 or 30 years, it’s just a question of time,” said Kim Cobb, an oceanographer at Georgia Tech. “The overall health of reefs will be severely compromised by the mid-point of the century and we are already seeing the first steps in that process.”
The researchers said that 90% of Hawaii’s reefs now exhibit bleaching. Some areas have lost more than half their coral cover.
Bleaching is when warming ocean temperatures cause algae living inside coral to disappear. Coral need the algae to provide them with vital nutrients, so the algae’s departure leads to coral starving and losing their color to turn a bleach-like white. If the water does not return soon enough to cooler temperatures, the coral die. Global warming fuels bleaching because the oceans absorb about 90% of the added heat generated by surface-level greenhouse-gas emissions.
The U.S. coral reefs’ plight resembles similar bleaching taking place throughout the Great Barrier Reef near Australia. There, too, coral reefs have suffered massive die-offs in just the last two years, and researchers warn that the entire reef system could be dead by 2050.