A Sea Change in Global Warming?
For years now, we have been deluged with the news that the earth’s oceans are heating up as a result of changes in atmospheric composition resulting from the combustion of fossil fuels.
Typical of these was a 2005 story titled “Where’s The Heat? Think Deep Blue,” from United Press International, describing a recent paper in Science by NASA climate modeler James Hansen. UPI wrote that “Over the past ten years, the heat content of the ocean has grown dramatically.” This study covered more than just the ocean surface temperature, which can fluctuate considerably from year to year. Rather, by considering a much deeper layer (the top 2,500 feet), Hansen could actually calculate the increasing amount of heat that is being stored. According to UPI’s story, this provided “a match” with computer model projections of global warming.
The ocean is a huge flywheel that integrates and stores long-term climate changes. Consequently, when computer models are driven with ever-increasing atmospheric carbon dioxide, the deep oceans warm, warm, and warm. But it takes time to start up, just like a big pot of water heated by a small match. Once the process starts, though, nothing should be able to stop it.
That’s the current wisdom of our climate models, but like current wisdom on so many other aspects of life, nature has behaved differently.
Within weeks, a paper is going to appear in the refereed journal Geophysical Research Letters, by John Lyman of the National Oceanic and Atmospheric Administration, showing that, globally, the top 2500 feet of the ocean lost a tremendous amount of heat between from 2003 through 2005—about 20% of all the heat gained in the last half-century.