Featured Research

from universities, journals, and other organizations

Higher Ocean Temperatures Linked To Cooling In Midwest

Date:
January 22, 2001
Source:
University Of Illinois At Urbana-Champaign
Summary:
While Earth as a whole has warmed during the last half-century, much of the continental United States has grown slightly colder. The trend toward cooler temperatures in the central and eastern United States is due to warmer ocean temperatures, a University of Illinois researcher says.

CHAMPAIGN, Ill. — While Earth as a whole has warmed during the last half-century, much of the continental United States has grown slightly colder. The trend toward cooler temperatures in the central and eastern United States is due to warmer ocean temperatures, a University of Illinois researcher says.

Related Articles


"Although portions of the U.S. have failed to get warmer, they have gotten cloudier," said Walter Robinson, a UI professor of atmospheric sciences. "Our models suggest there is a strong correlation between this increased cloudiness and higher sea-surface temperatures in the tropical Pacific Ocean."

Conventional wisdom has associated the lack of warming with the influence of anthropogenic aerosols, such as sulfate particles, Robinson said. Unlike greenhouse gases – which contribute to global warming – sulfate particles have a cooling effect. Coal-burning power plants in the Midwest are a major source of such particles.

"The implication has been that if emissions of these particles continue to increase, it could be quite a long time before we experience global warming in the central and eastern U.S.," Robinson said. "If aerosols are not responsible for the cooling, however, we could feel the heat much sooner."

Robinson and his colleagues – James Hansen at the NASA Goddard Institute for Space Studies and Reto Reudy at Science Systems and Applications Inc. – used an atmospheric general circulation model to study the effects of changes in sea-surface temperature on regional cooling in the United States.

The researchers used ocean temperature data from 1950 to 1997. By holding the levels of aerosols, solar irradiance and greenhouse gases constant, the team eliminated them as causes of the cooling.

The model exhibited cooling only when the observed, time-varying tropical ocean temperatures were imposed, Robinson said. Also, the model became cloudier directly over the regions that became cooler, indicating moisture transport was the responsible mechanism. "Warmer sea-surface temperatures in the tropical Pacific Ocean release additional water vapor, which gets swept across Central America and the Gulf of Mexico into North America, where it generates increased cloud cover over the central and eastern U.S.," Robinson said. "By reflecting more solar radiation back into space, this additional cloud cover is directly responsible for the cooling."

While the mystery of the cooling trend may be solved, a deeper question remains: Is the effect a manifestation of global warming, or is it a result of natural variability in the climate system?

"If the tropics are getting warmer because of global warming, then we can expect the cooling trend in the U.S. to continue," Robinson said. "But, if the effect is due to natural variability – and historical records indicate that recent temperature variations in the tropical Pacific are not unusual – then it’s only a matter of time before our temperatures ‘catch-up‘ with the rest of the world."

Robinson presented the team’s findings at a meeting of the American Meteorological Society, held Jan. 14-19, in Albuquerque, N.M. This work was supported by the National Science Foundation.


Story Source:

The above story is based on materials provided by University Of Illinois At Urbana-Champaign. Note: Materials may be edited for content and length.


Cite This Page:

University Of Illinois At Urbana-Champaign. "Higher Ocean Temperatures Linked To Cooling In Midwest." ScienceDaily. ScienceDaily, 22 January 2001. <www.sciencedaily.com/releases/2001/01/010122075851.htm>.
University Of Illinois At Urbana-Champaign. (2001, January 22). Higher Ocean Temperatures Linked To Cooling In Midwest. ScienceDaily. Retrieved October 31, 2014 from www.sciencedaily.com/releases/2001/01/010122075851.htm
University Of Illinois At Urbana-Champaign. "Higher Ocean Temperatures Linked To Cooling In Midwest." ScienceDaily. www.sciencedaily.com/releases/2001/01/010122075851.htm (accessed October 31, 2014).

Share This



More Earth & Climate News

Friday, October 31, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

How A Chorus Led Scientists To A New Frog Species

How A Chorus Led Scientists To A New Frog Species

Newsy (Oct. 30, 2014) A frog noticed by a conservationist on New York's Staten Island has been confirmed as a new species after extensive study and genetic testing. Video provided by Newsy
Powered by NewsLook.com
Raw: Hawaii Lava Approaching Village Road

Raw: Hawaii Lava Approaching Village Road

AP (Oct. 30, 2014) The lava flow on the Big Island of Hawaii was 225 yards from Pahoa Village Road on Wednesday night. The lava is slowing down but still approaching the village. (Oct. 30) Video provided by AP
Powered by NewsLook.com
Endangered Carpathian Ponies Are Making a Comeback in Poland

Endangered Carpathian Ponies Are Making a Comeback in Poland

AFP (Oct. 29, 2014) At the foot of the rugged Carpathian mountains near the Polish-Ukrainian border, ranchers and scientists are trying to protect the Carpathian pony, known as the Hucul in Polish. Duration: 02:17 Video provided by AFP
Powered by NewsLook.com
Deadly Mudslide in Sri Lanka Buries Houses

Deadly Mudslide in Sri Lanka Buries Houses

AP (Oct. 29, 2014) A mudslide triggered by monsoon rains buried scores of workers' houses at a tea plantation in central Sri Lanka on Wednesday, killing at least 10 people and leaving more than 250 missing, an official said. (Oct. 29) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins