Between 2009 and 2018, about 14 percent of the world's coral was lost, primarily due to climate change, scientists say in a report released Tuesday by the Global Coral Reef Monitoring Network.
Coral reefs are found in more than 100 countries around the world, providing habitat for about 25 percent of marine life while also serving as a source for food, jobs, and medicine. The study is the largest-ever analysis of coral reef health, with data collected by 300 scientists in 73 countries over the span of four decades. It also found that between 2010 and 2019, reef algae — which grows when coral is stressed — increased by 20 percent.
Higher sea surface temperatures caused by global warming are the main factor in coral bleaching events, the scientists said, with overfishing and coastal developments also playing a role in coral loss. "There are clearly unsettling trends toward coral loss, and we can expect these to continue as warming persists," Paul Hardisty, CEO of the Australian Institute of Marine Science, told The Guardian. "Despite this, some reefs have shown a remarkable ability to bounce back, which offers hope for the future recovery of degraded reefs."
Hardisty said the study has a "clear message," and that is "that climate change is the biggest threat to the world's reefs, and we must all do our part by urgently curbing global greenhouse gas emissions and mitigating local pressures."