Recent Heat Waves Permanently Damaged Australia’s Great Barrier Reef, Study Says
A third of the Great Barrier Reef, the largest coral reef in the world, experienced irreversible damage after record-breaking heat waves caused by global warming, according to a study published last Wednesday.
The ecological functionality of about 29 percent of the area’s 3,863 coral reefs has been permanently altered, a result that could prove devastating to the reef’s rich ecosystem and Australia’s economy. Stretching across the coast of Queensland, The Great Barrier Reef is not only home to thousands of different marine species, but it also supports 64,000 jobs and contributes over $5 billion annually to the country’s economy. The entire area also covers 344,400 kilometers, making it roughly the size of Japan or Germany.
Its economic and ecological importance, however, doesn’t exempt it from the fatal effects of global warming. More than 90 percent of heat caused by manmade global warming is absorbed by the ocean, leading to events like the record-breaking marine heat wave that hit the Great Barrier Reef in 2016. This heat wave was also exacerbated by El Niño and local weather patterns.
Coral reefs are very sensitive. When they undergo slight changes in temperature, light, or nutrients, they expel symbiotic algae in their tissues and lose their color — a process known as coral bleaching. While bleached corals aren't dead, they become more vulnerable to disease and mortality. The Great Barrier Reef has bleached four times since 1998, although the 2016 coral bleaching proved to be the most severe.
Researchers from the Australian Research Council Centre of Excellence for Coral Reef Studies at James Cook University authored the study, which was published in Nature, an international science journal. Terry P. Hughes, the lead author of the study, told the New York Times that “We’re in uncharted territory. Where we end up depends completely on how well or how badly we deal with climate change.”
The future of the Great Barrier Reef is not entirely bleak. If countries are able to adhere to the Paris Agreement, which has a goal of reducing greenhouse gas emissions in order to keep global temperatures from rising above 2 degrees Celsius, the Australian coral reef may be preserved for up to 50 years, according to the study. However, the U.S. announced their withdrawal from the climate accord last summer despite being the second largest emitter of greenhouse gases in the world.
Other than climate change, poor water quality from land-based runoff, coastal development, and illegal fishing also pose a threat to the Great Barrier Reef.
The government of Australian Prime Minister Malcolm Turnbull announced plans to invest $60 million towards protecting the Great Barrier Reef this past January. This plan will increase the number of field officers protecting the area and the number of vessels targeting crown-of-thorns starfish. Additionally, it plans to incentivize farmers to reduce the amount of pollution flowing into the reef.