Abnormally strong trade winds since the 1990s have blown across the Pacific, possibly trapping heat from the air in the ocean’s waters. This may explain why average global temperatures increased less than some computer models predicted.
However, when the winds slow down to normal, the heat could escape quickly and cause rapid warming of the Earth’s atmosphere, suggests new research.
Although still approximately 1.53 degrees F (0.85 C) warmer than in 1880, the Earth’s atmospheric fever has held relatively steady during the past decade.
The reason for that climate change plateau puzzles atmospheric scientists. The answer may be blowing in the trade winds, persistent surface winds that flow from East to West near the equator.
“Scientists have long suspected that extra ocean heat uptake has slowed the rise of global average temperatures, but the mechanism behind the hiatus remained unclear,” said Matthew England of the University of New South Wales and lead author of the recent study published in Nature Climate Change, in a press release.
Faster-than-normal trade winds may have been the previously unknown mechanism for hiding heat in the ocean. England’s team incorporated these unusually intense winds into global climate models. In the model, as the winds sped up over the Pacific Ocean in the ’90s, they forced warmer surface water down. Cooler, deeper water then flowed to the surface. The results of the models closely matched the real world’s climate change plateau.
“Unfortunately, however, when the hiatus ends, global warming looks set to be rapid,” said England. “We should be very clear: The current hiatus offers no comfort -- we are just seeing another pause in warming before the next inevitable rise in global temperatures.”
Photo: A sailboarder takes advantage of the trade winds off the coast of the United States. Credit: Šarūnas Burdulis, Wikimedia Commons