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.



You May Like

Photogallery Brussels Schools, Metro Reopen Under Heavy Guard

City remains under the highest threat alert level due to what authorities have described as a 'serious and imminent' threat of attack

Video Debt-ridden Refugees Await Onslaught of Lebanese Winter

Aid agencies are attempting to reduce potentially devastating consequences of freezing conditions and snowstorms that killed eight last year, including three Syrian refugees

UN Warns Air Pollution in Asia Pacific Has Rising Cost

Globally some seven million people a year die prematurely due to indoor and outdoor pollution with about 70 per cent of those deaths in region

This forum has been closed.
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?

Featured Videos

Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
After Paris Attacks, France Steps Up Fight Against ISi
November 24, 2015 3:04 AM
The November 13 Paris attacks have drawn increased attention to Syria, where many of the suspected perpetrators are said to have received training. French President Francois Hollande is working to build a broad international coalition to defeat Islamic State in Syria and in Iraq. Zlatica Hoke reports.

Video After Paris Attacks, France Steps Up Fight Against IS

The November 13 Paris attacks have drawn increased attention to Syria, where many of the suspected perpetrators are said to have received training. French President Francois Hollande is working to build a broad international coalition to defeat Islamic State in Syria and in Iraq. Zlatica Hoke reports.

Video US, Cambodian Navies Pair Up in Gulf of Thailand

The U.S. Navy has deployed one of its newest and most advanced ships to Cambodia to conduct joint training drills in the Gulf of Thailand. Riding hull-to-hull with Cambodian ships, the seamen of the USS Fort Worth are executing joint-training drills that will help build relations in Southeast Asia. David Boyle reports for VOA from Preah Sihanouk province.

Video Americans Sharpen Focus on Terrorism

Washington will be quieter than usual this week due to the Thanksgiving holiday, even as Americans across the nation register heightened concerns over possible terrorist threats. VOA’s Michael Bowman reports new polling data from ABC News and the Washington Post newspaper show an electorate increasingly focused on security issues after the deadly Islamic State attacks in Paris.

Video World Leaders Head to Paris for Climate Deal

Heads of state from nearly 80 countries are heading to Paris (November 30-December 11) to craft a global climate change agreement. The new accord will replace the Kyoto Protocol on Climate Change that expired in 2012.

Video Uncertain Future for Syrian Refugee Resettlement in Illinois

For the trickle of Syrian refugees finding new homes in the Midwest city of Chicago, the call to end resettlement in many U.S. states is adding another dimension to their long journey fleeing war. Organizations working to help them integrate say the backlash since the Paris attacks is both harming and helping their efforts to provide refugees sanctuary. VOA's Kane Farabaugh reports.

Video Creating Physical Virtual Reality With Tiny Drones

As many computer gamers know, virtual reality is a three-dimensional picture, projected inside special googles. It can fool your brain into thinking the computer world is the real world. But If you try to touch it, it’s not there. Now Canadian researchers say it may be possible to create a physical virtual reality using tiny drones. VOA’s George Putic reports.

Video New American Indian Village Takes Visitors Back in Time

There is precious little opportunity to experience what life was like in the United States before its colonization by European settlers. Now, an American Indian village built in a park outside Washington is taking visitors back in time to experience the way of life of America's indigenous people. Carol Pearson narrates this report from VOA's June Soh.

Video Even With Hometown Liberated, Yazidi Refugees Fear Return

While the northern Iraqi town of Sinjar has been liberated from Islamic State forces, it's not clear whether Yazidi residents who fled the militants will now return home. VOA’s Mahmut Bozarslan talked with Yazidis, a religious and ethnic minority, at a Turkish refugee camp in Diyarbakır. Robert Raffaele narrates his report.

Video Nairobi Tailors Make Pope Francis’ Vestments

To ensure the pope is properly attired during his visit, the Kenya Conference of Catholic Bishops asked the Dolly Craft Sewing Project in the Nairobi slum of Kangemi to make the pope's vestments, the garments he will wear during the various ceremonies. Jill Craig reports.

Video Cross-Border Terrorism Puts Europe’s Passport-Free Travel in Doubt

The fallout from the Islamic State terror attacks in Paris has put the future of Europe’s passport-free travel area, known as the "Schengen Zone," in doubt. Several of the perpetrators were known to intelligence agencies, but were not intercepted. Henry Ridgwell reports from London European ministers are to hold an emergency meeting Friday in Brussels to look at ways of improving security.

Video El Niño Brings Unexpected Fish From Mexico to California

Fish in an unexpected spectrum of sizes, shapes and colors are moving north, through El Niño's warm currents from Mexican waters to the Pacific Ocean off California’s coast. El Nino is the periodic warming of the eastern and central Pacific Ocean. As Faiza Elmasry tells us, this phenomenon thrills scientists and gives anglers the chance of a once-in-a-lifetime big catch. Faith Lapidus narrates.

Video Terrorism in Many Forms Continues to Plague Africa

While the world's attention is on Paris in the wake of Friday night's deadly attacks, terrorism from various sides remains a looming threat in many African countries. Nigerian cities have been targeted this week by attacks many believe were staged by the violent Islamist group Boko Haram. In addition, residents in many regions are forced to flee their homes as they are terrorized by armed militias. Zlatica Hoke reports.

Video Study: Underage Marriage Rate Higher for Females in Pakistan

While attitudes about the societal role of females in Pakistan are evolving, research by child advocacy group Plan International suggests that underage marriage of girls remains a particularly big issue in the country. VOA’s Ayesha Tanzeem reports how such marriages leads to further social problems.

VOA Blogs