Researchers from Scripps Institution of Oceanography and Princeton University released a study Thursday that concludes the world’s oceans are heating up faster than expected, making it more difficult to stop climate change.
The study, published in the journal Nature, found the Earth is more sensitive to fossil-fuel emissions than previously thought. In each of the past 25 years, according to new measurements, oceans have absorbed an amount of heat energy that is 150 times the energy humans produce as electricity annually.
Last summer record ocean temperatures — the highest 79.2 degrees — were recorded at Scripps Pier in La Jolla.
Oceans take up roughly 90 percent of all the excess energy produced as the Earth warms, so knowing the actual amount of energy makes it possible to estimate the surface warming that can be expected.
Lead author Laure Resplandy, a Princeton assistant professor of geosciences, said that if society is to prevent temperatures from rising above pre-industrial levels by 2℃ (3.6℉), emissions of carbon dioxide must be reduced by 25 percent more than previously estimated.
Resplandy said the new estimate of ocean warming is more than 60 percent higher than the figure in the latest climate change report from the United Nations Intergovernmental Panel on Climate Change.
“Imagine if the ocean was only 30 feet deep,” said Resplandy, a former postdoctoral researcher at Scripps. “Our data shows that it would have warmed by 6.5℃ (11.7℉) every decade since 1991. In comparison, the estimate of the last IPCC assessment report would correspond to a warming of only 4℃ (7.2℉) every decade.”
The study, “Quantification of ocean heat uptake from changes in atmospheric O2 and CO2 composition,” was funded by the Climate Program Office of the National Oceanic and Atmospheric Administration and the Princeton Environmental Institute.