Missing heat has shown up in the oceans, particularly in shallow tropical depths.
Shutterstock / Willyam BradberryMissing heat has shown up in the oceans, particularly in shallow tropical depths.

Pity the oceans. Not only do we dump oil and plastics and all kinds of nasty chemicals and garbage into them. Turns out we’re dumping heat into them too.

Studies of ocean temperatures are revealing that a lot of the excess heat we’re creating by pumping greenhouse gases into the atmosphere is ending up in the oceans.

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That’s helping to keep the atmosphere cooler than scientists had previously projected; the rise in surface temperatures slowed during the first decade of this century. (The effects of aerosols spat out by volcanoes and other phenomena are also thought to have helped keep temperatures on the surface of Earth lower than expected.) That may seem a good thing from the perspective of terrestrial creatures like us. But the oceans won’t suck up all that heat forever.

A new paper published in Nature Climate Change by scientists from Spain and France identified where much of the missing heat had ended up:

Most of this excess energy was absorbed in the top 700 [meters] of the ocean at the onset of the warming pause, 65% of it in the tropical Pacific and Atlantic oceans. Our results hence point at the key role of the ocean heat uptake in the recent warming slowdown.

From Reuters:

Lead author Virginie Guemas of the Catalan Institute of Climate Sciences in Barcelona said the hidden heat may return to the atmosphere in the next decade, stoking warming again. …

Caroline Katsman of the Royal Netherlands Meteorological Institute, an expert who was not involved in the latest study, said heat absorbed by the ocean will come back into the atmosphere if it is part of an ocean cycle such as the “El Nino” warming and “La Nina” cooling events in the Pacific.

She said the study broadly confirmed earlier research by her institute but that it was unlikely to be the full explanation of the warming pause at the surface, since it only applied to the onset of the slowdown around 2000.

The study builds upon a paper published last month in the journal Geophysical Research Letters. That research, as summarized by the blog Skeptical Science, found that “about 90% of overall global warming goes into heating the oceans, and the oceans have been warming dramatically” during the past 15 years. “The slowed surface air warming over the past decade has lulled many people into a false and unwarranted sense of security.”

So it seems that before we bake our own homes, we’re going to boil the oceans. And then our homes will be baked anyway.