Diver in the Great Barrier Reef. Picture: Australian Press/David Gray/AFP
Australia's Great Barrier Reef is experiencing one of the worst coral bleaching events ever recorded. The Great Barrier Marine Park Authority, the organization that manages the reef, announced on Wednesday that 73% of the reefs studied were damaged.
Coral bleaching occurs when the water temperature rises more than one degree Celsius. The algae that provide coral color are flushed out by high temperatures, eventually turning the coral white. The current mass bleaching event due to rising water temperatures caused by climate change is the fifth in eight years. Atmospheric observations show that about six hundred corals have bleached.
Ten percent of the area is considered highly bleached. This occurs when more than 90 percent of the reef is affected and is unlikely to survive. Although coral reefs can recover from bleaching, the period between the two bleaching events is becoming shorter. As global temperatures continue to rise, scientists expect bleaching to reduce global coral cover by 95 percent as temperatures rise by about 2 degrees.
to heat up
The US National Oceanic and Atmospheric Administration (NOAA) announced Monday that coral bleaching has occurred worldwide for the second time in a decade. “As the world’s oceans continue to warm, coral bleaching is occurring with increasing frequency and severity,” NOAA said.
The Great Barrier Reef is the largest coral reef in the world. It extends 2,300 kilometers off the northeastern coast of Australia, and is home to more than six hundred species of coral and 1,625 species of fish.
