SYDNEY, Aug. 31 (Xinhua) -- The world's coral reefs are losing the time they need to recover between increasingly frequent marine heatwaves and global bleaching events driven by human-induced climate change, a report said on Monday.
The Status of Coral Reefs of the World: 2025, published by the Global Coral Reef Monitoring Network (GCRMN), is the most comprehensive assessment of coral reefs to date, drawing on more than 40 years of global data from 21.1 million observations, 87,299 surveys, representing 36,886 sites across 124 countries, territories and economies, according to a GCRMN statement.
"Climate change is driving more frequent and severe marine heatwaves, but local pressures such as poor water quality, overfishing and coastal development are making reefs even less able to withstand them," said the report's lead author Manuel Gonzalez Rivero from the Australian Institute of Marine Science.
Global hard coral cover declined by about 9.5 percent, from an average of 30.2 percent during 1980-2009 to 27.3 percent in 2020-2024, with climate change-driven heat stress identified as the primary cause.
Four major global bleaching events since 1998 have reduced hard coral cover, with reefs only partially recovering between events.
Major bleaching events previously occurred about once a decade. Since 2010, they have occurred approximately every five to six years. However, many corals need at least five years just to mature and begin reproducing.
"Coral reefs once had decades to recover after major bleaching events. Today, they're lucky to get five or six years," said Gonzalez Rivero.
The report said ambitious reductions in greenhouse gas emissions, combined with effective management of local pressures, offer the strongest pathway to maintain hard coral cover. ■
