Recent Study Finds Oceans Absorbed 60% More Heat Than Previously Thought
A study published on Nov. 1 has found that the world’s oceans absorbed 60% more heat per year than was previously thought. The study, which was published in the journal Nature and funded by the Climate Program Office of the National Oceanic and Atmospheric Administration and the Princeton Environmental Institute, stated that ocean warming “is at the high end of previous estimates, with implications for policy- relevant measurements of the Earth response to climate change, such as climate sensitivity to greenhouse gases and the thermal component of sea-level rise.”
This increase in ocean temperatures means that more heat is retained in Earth’s climate system rather than being released into space, suggesting that climate change is at a more advanced stage than researchers thought. In other words, the Earth may be even more sensitive to factors like fossil fuel emissions than experts previously believed.
Laure Resplandy, first author of the paper and assistant professor of geosciences at the Princeton Environmental Institute, explained: “we thought that we got away with not a lot of warming in both the ocean and the atmosphere for the amount of CO2 that we emitted, but we were wrong. The planet warmed more than we thought. It was hidden from us just because we didn’t sample it right. But it was there. It was in the ocean already.”
There are several potential environmental implications of this heat retention, including sea levels rising faster than forecasted, more coral reefs dying, more powerful storms forming, increased melting of sea ice, and changes to ocean currents. Laurent Bopp, a co-author of the study and director of research at the Ecole Normale Supérieure in Paris, said that the findings were "bad news for the ocean itself, as well as bad news for the ecosystem."
The results of the study also have potential policy implications- according to Resplandy, “the researchers' findings suggest that if society is to prevent temperatures from rising above that mark, emissions of carbon dioxide, the chief greenhouse gas produced by human activities, must be reduced by 25 percent compared to what was previously estimated.” Essentially, nations are left with even less time to make a serious cut in carbon dioxide emissions in order to even come close to the goal of mitigating global warming.
Paul Durack, a research scientist at the Lawrence Livermore National Laboratory in California, stated that the study offers “a really interesting new insight,” while also underscoring the seriousness of its results. If further research continues to reflect the data in the study, Durack says, “it means the rate of warming and the sensitivity of the Earth’s system to greenhouse gases is at the upper end.” He added that if scientists have underestimated the amount of heat absorbed by the oceans, “it will mean we need to go back to the drawing board” on the aggressiveness of policy measures we need to take to limit future warming.