Featured Research

from universities, journals, and other organizations

Scientists Zero In On Arctic, Hemisphere-Wide Climate Swings

Date:
August 30, 2002
Source:
University Of Washington
Summary:
In the late 1990s, as scientists were reaching consensus that the Arctic had gone through 30 years of significant climate change, they began reading the first published papers about the Arctic Oscillation, a phenomenon reported to have hemisphere-wide effects.

In the late 1990s, as scientists were reaching consensus that the Arctic had gone through 30 years of significant climate change, they began reading the first published papers about the Arctic Oscillation, a phenomenon reported to have hemisphere-wide effects.

Related Articles


In short order the arctic-science and the global-change communities were galvanized, says Richard Moritz, polar oceanographer with the UW's Applied Physics Laboratory and lead author of a review of recent Arctic climate change in the Aug. 30 special polar-science issue of Science.

"We've learned more about the dynamics of post-glacial arctic climate change in the last five years than in the 50 years previous," Moritz says. "For example, the recent trend in the Arctic Oscillation explains the warming observed in the Arctic better than anything else."

Advances in understanding arctic climate change are particularly timely, with some studies indicating that the recent trend in the Arctic Oscillation results partly from human activities that generate greenhouse gases and sulfate particles, and deplete stratospheric ozone. Scientists, planners and policymakers need to know what the changes of the last 30 years portend.

Thus climate modelers have redoubled their efforts to determine the physics behind the patterns of change. Although their models portray realistic day-to-day and month-to-month variations in the Arctic Oscillation, they fail to capture the magnitude of the longer term trend in the Arctic Oscillation that was observed from 1970 to 2000. While paleoclimatologists studying the climate record of the past 1,000 years have not reached a consensus on the importance of the Arctic Oscillation pattern over this longer period, some surprising findings indicate that past Arctic warmings tended to coincide with low-frequency El Nino-Southern Oscillation events in the tropical Pacific.

The review by Moritz and co-authors Cecilia Bitz, a sea-ice expert with the UW's Applied Physics Laboratory, and Eric Steig, assistant professor with the UW's Quaternary Research Center, refers to more than 80 published papers, most appearing in just the last two years. The co-authors say that warming of the surface from 1970 to 2000 in the Northern Hemisphere was greatest in the Arctic, causing changes in precipitation, snow cover and the extent of sea ice.

The Arctic Oscillation is a seesaw pattern in which atmospheric pressure at the polar and middle latitudes fluctuates between positive and negative phases. The wind patterns associated with the Arctic Oscillation affect the surface temperature over North America and Eurasia, as well as the Arctic. The Arctic Oscillation was first described in a 1998 article by David Thompson, then a graduate student at the UW and now an assistant professor at Colorado State University, and John M. Wallace, a UW professor.

"The Arctic Oscillation provides a very fruitful framework and the result is that a tremendous amount of work has been done in a relatively short period of time," Moritz says. "Attempts to model the pattern of recent Arctic and global warming have to come to grips with the problem of the Arctic Oscillation." Climate modelers have benefited from a growing understanding of sea-ice physics and the best-ever measurements of how heat from the sun and the atmosphere affects the pack ice that covers the Arctic Ocean. Moritz, for example, is director of the SHEBA (Surface Heat Budget of the Arctic Ocean) Project Office funded by the National Science foundation and Office of Naval Research. Now in its analysis phase, SHEBA locked an icebreaker into the pack ice for a full year in the late '90s to measure the interactions of the ice, atmosphere and the ocean during all four seasons.

Because so many climate modelers worldwide are working on the Arctic Oscillation, Moritz says it's conceivable that in a year or two we will understand the fundamental physics of the Arctic Oscillation, and be able to account for its recent trend. "If we can't, it won't be for lack of trying."


Story Source:

The above story is based on materials provided by University Of Washington. Note: Materials may be edited for content and length.


Cite This Page:

University Of Washington. "Scientists Zero In On Arctic, Hemisphere-Wide Climate Swings." ScienceDaily. ScienceDaily, 30 August 2002. <www.sciencedaily.com/releases/2002/08/020830071739.htm>.
University Of Washington. (2002, August 30). Scientists Zero In On Arctic, Hemisphere-Wide Climate Swings. ScienceDaily. Retrieved October 24, 2014 from www.sciencedaily.com/releases/2002/08/020830071739.htm
University Of Washington. "Scientists Zero In On Arctic, Hemisphere-Wide Climate Swings." ScienceDaily. www.sciencedaily.com/releases/2002/08/020830071739.htm (accessed October 24, 2014).

Share This



More Earth & Climate News

Friday, October 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Dances With Wolves in China's Wild West

Dances With Wolves in China's Wild West

AFP (Oct. 23, 2014) — One man is on a mission to boost the population of wolves in China's violence-wracked far west. The animal - symbol of the Uighur minority there - is under threat with a massive human resettlement program in the region. Duration: 00:41 Video provided by AFP
Powered by NewsLook.com
San Diego Zoo's White Rhinos Provide Hope for the Critically Endangered Species

San Diego Zoo's White Rhinos Provide Hope for the Critically Endangered Species

Reuters - Light News Video Online (Oct. 22, 2014) — The pair of rare white northern rhinos bring hope for their species as only six remain in the world. Elly Park reports. Video provided by Reuters
Powered by NewsLook.com
Trick-or-Treating Banned Because of Polar Bears

Trick-or-Treating Banned Because of Polar Bears

Buzz60 (Oct. 21, 2014) — Mother Nature is pulling a trick on the kids of Arviat, Canada. As Mara Montalbano (@maramontalbano) tells us, the effects of global warming caused the town to ban trick-or-treating this Halloween. Video provided by Buzz60
Powered by NewsLook.com
Traditional Farming Methods Gaining Ground in Mali

Traditional Farming Methods Gaining Ground in Mali

AFP (Oct. 20, 2014) — He is leading a one man agricultural revolution in Mali - Oumar Diatabe uses traditional farming methods to get the most out of his land and is teaching others across the country how to do the same. Duration: 01:44 Video provided by AFP
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