March 16, 2017

Stopping global warming is the only way to save coral reefs

Large swaths of the Great Barrier Reef, extending for hundreds of miles along its northern section, were recently discovered to be dead, wiped out last year by water that was too warm, according to a new report in the journal Nature.

Areas near the core of the reef that barely avoided destruction last year are now bleaching, a possible forerunner to another die-off that could erase many of the reef’s most visited areas of color and biodiversity.

"Climate change is the single greatest threat to the Great Barrier Reef," study author Morgan Pratchett, a researcher from James Cook University in Australia, told BBC News. "It all comes down to what the governments in Australia and around the world do in terms of mitigating further rises in temperatures."

Incredibly Sensitive Ecosystem

Corals need warm water to prosper, but they are remarkably sensitive to heat. Only two or three degrees F of surplus warming can kill the small creatures. Average global ocean temperatures have gone up by around 1.5 degrees Fahrenheit since the late 19th century. The increase has been a bit more dramatic in the tropics, where most reefs are located.

The damage to the Great Barrier Reef is part of a global catastrophe that has been taking place sporadically for almost 20 years and appears to be accelerating. In the new report, tens of researchers referred to the recent disaster as the third international mass bleaching of coral reefs since 1998, and quite possibly the most extensive and destructive.

Experts have said the health of coral reefs translates to the overall health of the oceans. Their stress and deaths are just one more sign of the forces of global climate change.

If most of the planet's coral reefs are killed, as researchers fear is increasingly becoming a possibility, some of the most unique and colorful life in the ocean might be lost, along with enormous revenues that come from ecotourism. In developing nations, lives are actually at stake, as millions of people have reef fish as a food source.

Pratchett told BBC News he believed it is still possible to stop the damage currently being done to The Great Barrier Reef by curbing emissions. However, the something must be done soon because the “window of opportunity” is closing.


Image credit: Tane Sinclair-Taylor/ARC Centre of Excellence for Coral Reef Studies/NOAA