Loss of Tropical Coral Reefs Could Be First Irreversible Climate Consequence

Tropical coral reefs form the very foundation of marine biodiversity.  Scientists are now increasingly worried that the acidification of the oceans is likely to cause one of the first abrupt, severe and probably irreversible consequences of global climate change: the loss of tropical coral reefs.

That’s the conclusion of a comprehensive new report on abrupt climate changes from the National Academy of Sciences.  Researchers have long hypothesized about climate-induced points of no return, like sudden catastrophic melting of ice caps or a dramatic shift in the Gulf stream, but the Academy report emphasizes that ecosystem collapse as environmental conditions steadily march past livable thresholds is much more likely in the next few decades.  And tropical coral reefs are one of the most precarious ecosystems, thanks to increasingly warm and acidic oceans.

Climate change poses a double threat to coral reefs.  Warming ocean waters lead to a potentially fatal process known as coral “bleaching,” in which reef-building corals eject algae living inside their tissues that supply them with most of their food.  Coral bleaching occurs when water temperatures are just 2-4°F above normal summertime temperatures. Bleached corals are weak and often succumb to disease.

The future costs to people who depend on the oceans for their livelihoods could run into trillions of dollars.  Some industries, notably in shellfish aquaculture, are already seeing the effects.

Loss of Tropical Coral Reefs Could Be First Irreversible Climate Consequence