Coral Reefs and Climate Change
Status of Coral Reefs

Coral Reefs have already suffered greatly from human-induced impacts, including global climate change. The Global Coral Reef Monitoring Network produced a status report in 2004 that concluded that 20% of the world's reefs have already been effectively destroyed beyond recovery. Another 24% are at risk of imminent collapse (Wilkinson 2004).

The most widespread and significant factor that is affecting coral reefs is coral bleaching associated with elevated sea surface temperatures. In 1998, 16% of the world's coral reefs suffered severe bleaching from an unusually strong El Nino event (Wilkinson 2004) (map below, from www.reefbase.org).

About 40% of the reefs affected by this bleaching event are already showing signs of recovery (Wilkinson 2004), which is encouraging. However, if El Nino and bleaching events of this magnitude start to occur more frequently, as is expected to happen as part of global climate change, then these reefs will not be able to recover.

Other human impacts besides climate change are impacting coral reefs as well, including overfishing, coastal development, and pollution (Wilkinson 2004). These impacts are degrading reefs and making them even more susceptible to the impacts of climate change. In the Caribbean, there has already been an 80% decline in live coral cover in many areas due to various human activities (Wilkinson 2004). Southeast Asian reefs are also under particularly high pressure from human activities. Reefs in the Pacific and Australia, however, remain quite healthy under good management regimes (Wilkinson 2004).