Given Lew and Oreskes latest admonition to scientists who use the word “pause” or “hiatus” it looks like they’ll be applying the “D” word to the entire AGU community of scientists any minute now. From the AGU website, EOS:
Tracking the Missing Heat from the Global Warming Hiatus
Despite indications that the Pacific Ocean is helping to take up the world’s missing surface heat, the heat doesn’t linger; oceanographers now find that heat has moved over to the Indian Ocean.
Illustration of increased trade winds in the Pacific and Indian Oceans during the recent warming hiatus, which enhanced the flow of ocean water through the Indonesian archipelago. This resulted in an abrupt increase of Indian Ocean heat content. Credit: Sang-Ki Lee
By Christina Reed 21 May 2015
At the end of the 20th century, climate scientists noticed what they thought at first was an anomaly: a slowdown in the pace of global warming in the lower atmosphere. Today, it is a recognized trend that has lasted more than 15 years. Perplexed, oceanographers are on a hunt to find where this missing heat has gone.
In the latest report out of Nature Geoscience this week, University of Miami physical oceanographer Sang-Ki Lee and colleagues may have found some of this missing heat: The Pacific Ocean is keeping its cool by sending heat over to the Indian Ocean. This heat redistribution, the researchers say, could play a role in regulating the rate of global warming.
Oceans: A Complex Buffer
Rather than showing any signs of storing heat, as is the case in the Atlantic Ocean, the Pacific Ocean has actually cooled over the last decade.Why the global warming hiatus has happened and how long it will last is a mystery. However, scientists do know that the ocean has recently helped to buffer what was otherwise an accelerated surface warming, one that has not yet stopped. Warming in the upper atmosphere continues to show that the planet is undergoing a radiation imbalance.
However, rather than showing any signs of storing heat, as is the case in the Atlantic Ocean, the Pacific Ocean has actually cooled over the last decade.
“When I noticed from the hydrographic data that the Pacific Ocean heat content has been decreasing since 2003 or so, I was very surprised and puzzled,” Lee told Eos. “And when I found a large heat increase in the Indian Ocean, I was almost convinced that there was something wrong with the hydrographic data.”
How Does Heat Escape to the Indian Ocean?
Lee ran a computer model simulation and found that he could explain the difference if a massive amount of heat from the Pacific flowed through Indonesia’s archipelago into the Indian Ocean. However, how best to move the heat?
Warm water, like warm air, rises—or, rather, stays at the surface when nothing else is disturbing it. This is why, in a lake, the upper layer is warmer than the bottom layer.
To get warm surface water from the Pacific to the Indian Ocean requires wind—and not just any wind. The trade winds need to be strong enough to push water from the eastern Pacific all the way across the ocean basin to the west, where it piles up and creates a region of above-average sea surface height.
Warm surface water can then flow like a river down around the Indonesian archipelago to the Indian Ocean. A difference in height of less than a dozen centimeters is enough to get the heat moving.
Full story here: https://eos.org/articles/tracking-the-missing-heat-from-the-global-warming-hiatus
Citation: Reed, C. (2015), Tracking the missing heat from the global warming hiatus, Eos, 96, doi:10.1029/2015EO029947. Published on 21 May 2015.