Chronic Ocean Heating Fuels ‘Staggering’ Loss of Marine Life, Study Finds

Chronic ocean heating is fuelling a “staggering and deeply concerning” loss of marine life, a study has found, with fish levels falling by 7.2% from as little as 0.1C of warming per decade. Researchers examined the year-to-year change of 33,000 populations in the northern hemisphere between 1993 and 2021, and isolated the effect of the decadal rate of seabed warming from short shifts such as marine heatwaves. They found the drop in biomass from chronic heating to be as high as 19.8% in a single year.

“To put it simply, the faster the ocean floor warms, the faster we lose fish,” said Shahar Chaikin, a marine ecologist at the National Museum of Natural Sciences in Spain and the study’s lead author. “A 7.2% decline for every tenth of a degree per decade might sound small,” he added. “But compounded over time, across entire ocean basins, it represents a staggering and deeply concerning loss of marine life.”