News / Science & Technology

Global Warming Slowdown Trapped in Ocean

General view of beach shows breaking waves along the ocean beach front in Biarritz on the southern Atlantic Coast of France, Feb. 6, 2014. Global warming is in a temporary hiatus, in part because of heat absorbed deep into the Atlantic and Southern oceans.
General view of beach shows breaking waves along the ocean beach front in Biarritz on the southern Atlantic Coast of France, Feb. 6, 2014. Global warming is in a temporary hiatus, in part because of heat absorbed deep into the Atlantic and Southern oceans.
Rosanne Skirble

A climate change mystery is coming into sharper focus.

A new study released in the journal Science explains why despite the rise of heat-trapping gases in the atmosphere, global warming has slowed over the last 15 years. Some scientists point to the cooling effect of volcanoes or changes in solar activity.  

Lead author and University of Washington applied mathematics professor Ka Kit Tung suggests massive movement of heat from shallow to deep regions of the ocean is responsible.

“From the energy standpoint, the warming does not just warm the surface. It should warm the whole ocean column," said Tung. "There is evidence that the integrated temperature of the whole ocean column has been increasing even through the current period of pause.”

Global warming heat stored in Atlantic, Southern oceans

Ninety-three percent of the excess heat caused by global warming gases is stored in the oceans. Tung used underwater sensors to measure the temperature at various depths in the water column over the last three decades of the 20th century. Climate models indicated that the Pacific Ocean was hiding the heat.

But observations showed the heat is sinking deep in the Atlantic and Southern Oceans, part of a natural 30-year cycle. Tung said the current phase, with cooler temperatures at the ocean surface, started in 1999 when the rapid warming of the last century slowed down. “And we are currently in the middle of this 30-year period where more heat is going into the ocean, Tung said, “That’s why what [heat] remains near the surface has not been much, not much warming.”    

Salty seawater triggers heat migration into ocean depth

Tung's study finds that the excessive heat now stored in the ocean depths moves like a conveyor belt between the north and south poles. The warm water becomes saltier as it travels through the subtropics because there is more evaporation of surface water at those latitudes.

Salty seawater is heavier and sinks, making the sea surface - and the air above it - cooler. Tung said that accounts for the warming pause we’re experiencing now. Temperatures will rise, however, when the ocean cycle flips to its warm phase. “The rate of surface temperature increase will be just as high, or even higher, than what we experienced in the last three decades of the 20th century. But the actual temperature that it starts with is now the highest temperature, but it is going to go up very rapidly. So the next phase of accelerated warming is going to be very damaging.”

The current global warming slowdown, Tung predicts, could last a decade or longer.



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Comment Sorting
by: Science Officer from: Earth
August 22, 2014 1:59 PM
Odd, the rate of sea level rise has slowed, commensurate with the "pause" in atmospheric temperatures. You'd think all the heat in the oceans would make them expand and sea levels would rise faster. Now we have another mystery to solve

by: Asok Smith
August 21, 2014 10:07 PM
I'm confused. I thought the "science" was settled.
In Response

by: Terry from: Western us
August 23, 2014 2:39 AM
I get tired of hearing the debate about climate change is settled. No "theory" that continually does not produce the projected results is settled. Every time things don't go the way the alarmists project they produce another theory as to why. They said themselves in this report that the earth goes through cycles of temperature fluctuation that can last up to 70 years. That meanes the last 100 years of warming, minus the last 15 years it didn't warm could be a natural cycle. We need to be good stewards of our planet but not destroy our economy based on unproven theory.
In Response

by: ReduceGHGs from: Oregon
August 22, 2014 11:08 AM
The science regarding the core issue is settled; Humans are warming the planet and the consequences are not good. To avoid confusion read what the experts have been saying for years. Google: NASA Climate Change Consensus

by: BigBob from: USA
August 21, 2014 9:13 PM
The big run-away green house is just a scare tactic to scare dumb weak minded folk to vote for surrendering extremely large amounts of tax money to greedy university profs. and other dishonest government officials. If you only knew the funds these greedy swindlers took in. Don’t forget crony capitalism like Solarendra and GE. Have a big green time while they suck green dollars from your pockets. One of the heads of IPCC Dr. Michael Mann and colleagues had all their top secret emails flooded into public domain where all could see the giant scam. You would think it would have been the end of the issue. But no! Way too much money to be made yet. Liberals run the government and liberals almost never indict fellow liberals. That’s because they are all a bunch of hippy crooks! You don't think I have proof ? Where has the social security funds gone to?

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