July 26, 2010

Bleaching Alert – Global Warming and El Nino – How bad will it get?

By Reef Check Executive Director Dr. Gregor Hodgson

2010 is now officially the hottest year ever recorded since temperature has been measured. Unfortunately coral reefs are the most sensitive ecosystem on earth to global warming. The previous hottest year was 1997/98 and Reef Check teams tracked the damage via bleached corals and ultimately the loss of about 10% of the world’s reef corals.

Corals are dependent upon their symbiotic algae for nutrition, and if the water becomes too warm for too long, the algae grow tails and simply swim away. If the now white “bleached” corals do not get their algae back after a couple of weeks, then they may die.

Unfortunately, reports have been coming in for two months from Southeast Asia and other parts of the world where water temperatures have exceeded normal levels resulting in massive bleaching in Thailand, Philippines, Malaysia (photo by Peter Heyes) and Indonesia.

Like 1998, it appears that the weather patterns associated with El Nino reduce wind mixing and wave action leading to pools of ocean water simply sitting and becoming overheated under clear skies.

Reef Check teams are working hard to track this new global bleaching event. As global warming continues, it is likely that these events will become more frequent. Several scientists have predicted that most coral reefs will be killed off in the next 50 years by global warming. But global warming can be stopped. Let’s all work to stop it in time.

For more information, visit NOAA’s Bleaching Outlook page.