A deadly combination of climate change and pollution could wipe out 70% to 90% of the world’s coral reefs in the next two decades, according to research presented at the 2020 Ocean Sciences Meeting in San Diego, California. The combination of rising temperatures in the ocean, pollution, and acidic water could, according to the research, kill all coral reefs by 2100. Scientists and advocates have pointed out the dangers of climate change for years, but the high rate of bleaching in coral reefs, in spite of increasing anti-pollution efforts, leaves the future for coral reef habitats, in the words of biogeographer Renee Setter, “looking quite grim.”
This study evaluated parts of the ocean that would work best for coral restoration efforts. To figure this out, scientists studied such factors as how frequently the areas are fished, water temperature, and human population size. Coral reefs are a virtual powerhouse of ocean ecosystems. Coral reef habitats protect coastlines (which, in turn, protect local communities and bring in tourism) and support diverse marine life systems. Increasing temperatures in the ocean rise (even just several degrees), leading to bleaching. Bleaching is, as the term suggests, when coral turns white, a process that occurs when the waters surrounding the reef warm. While bleaching itself usually doesn’t kill coral reef habitats (though in some severe cases, it can), it makes reefs much weaker and likelier to die.
According to the research, climate change is the biggest culprit behind the death of coral reefs. As the study notes, restoring coral reef habitats is great for now, but it isn’t enough on its own if climate change is not stopped.
"Trying to clean up the beaches is great and trying to combat pollution is fantastic. We need to continue those efforts," Setter said in a press release announcing the study results. "But at the end of the day, fighting climate change is really what we need to be advocating for in order to protect corals and avoid compounded stressors."
A growing number of people acknowledge climate change as the crisis that it is; the richest person in the world is putting up $10 billion to combat it; and Democratic presidential hopefuls are, to varying degrees, highlighting climate change and ocean restoration in their proposals. But with Trump in the White House, there’s no time to be complacent—climate change is already a crisis we need to tackle together.