Featured Research

from universities, journals, and other organizations

Scientist Find Clues To Different Warming Rates In Lower Atmosphere And Surface

Date:
February 18, 2000
Source:
National Center For Atmospheric Research (NCAR)
Summary:
Three factors--thinning of the ozone layer, emissions from Mt. Pinatubo, and the influx of sulfate aerosols and greenhouse gases into the atmosphere--may help explain why the lowest five miles of the earth's atmosphere has not warmed as quickly as the earth's surface, according to a paper in the February 18 issue of the journal Science.

BOULDER --- Three factors--the thinning of the ozone layer, emissionsfrom the Mt. Pinatubo volcano, and the influx of sulfate aerosols andgreenhouse gases into the atmosphere--may help explain why the lowestfive miles of the earth's atmosphere has not warmed as quickly as theearth's surface, say a group of scientists in a paper appearing inthe February 18 issue of the journal Science. The results followextensive data analysis and modeling studies by the 13 scientists.The team includes second author Tom Wigley and Gerald Meehl, bothscientists at the National Center for Atmospheric Research (NCAR).Lead author Ben Santer is at Lawrence Livermore National Laboratory.NCAR's primary sponsor is the National Science Foundation.

The difference in temperature trends at the surface and in the lowertroposphere has intensified the climate change debate. Some havepointed to the surface data as more reliable, while others havefocused on the satellite measurements. In January the NationalResearch Council (NRC) issued a report from a team of scientistsacross the spectrum of climate change positions that partlyreconciles the differences in data sets and offers some explanationof why the temperature trends would be different. The Santer-Wigleypaper, though not published at the time, was fully taken into accountin the report, says Kevin Trenberth, head of NCAR's Climate AnalysisSection and a coauthor of the NRC report.

For the Science paper, the team examined three observational datasets and recent model studies to reach their conclusions. The datasources are

--a century of thermometer readings of sea surface temperatures andair temperatures a few meters above land

--a half century of radiosonde measurements of troposphere and lowerstratosphere temperatures

--two decades of global observations of tropospheric temperatures (upto eight kilometers) taken by a series of satellites that measure theupwelling microwave radiation from oxygen molecules

Over the period 1979 to 1998, the surface data show a warming of 0.2-0.4 degree Celsius, while the radiosonde and satellite data show nowarming or only a slight temperature rise (0.1 degree C) in the lowertroposphere over the same period.

Neither complicated problems with the measurements nor the climate'sinherent variability over decades explains fully the temperaturetrend difference, say the authors. In a comprehensive modeling study,they found that the loss of stratospheric ozone and, to a lesserextent, the influx of Mt. Pinatubo emissions in the stratospherecooled the lower troposphere more than the surface. The model alsotook into account the buildup of greenhouse gases and sulfateaerosols.

Says Wigley, "This is a very complex problem with large uncertaintiesin the effects of human activities on the climate. However, we havereasonable confidence that ozone depletion and the Mt. Pinatuboemissions are likely candidates for explaining at least part of thecooler temperatures in the lower to middle troposphere compared tothe more intense warming at the surface."

NCAR is managed by the University Corporation for AtmosphericResearch, a consortium of more than 60 universities offering Ph.D.sin atmospheric and related sciences.


Story Source:

The above story is based on materials provided by National Center For Atmospheric Research (NCAR). Note: Materials may be edited for content and length.


Cite This Page:

National Center For Atmospheric Research (NCAR). "Scientist Find Clues To Different Warming Rates In Lower Atmosphere And Surface." ScienceDaily. ScienceDaily, 18 February 2000. <www.sciencedaily.com/releases/2000/02/000217165652.htm>.
National Center For Atmospheric Research (NCAR). (2000, February 18). Scientist Find Clues To Different Warming Rates In Lower Atmosphere And Surface. ScienceDaily. Retrieved October 22, 2014 from www.sciencedaily.com/releases/2000/02/000217165652.htm
National Center For Atmospheric Research (NCAR). "Scientist Find Clues To Different Warming Rates In Lower Atmosphere And Surface." ScienceDaily. www.sciencedaily.com/releases/2000/02/000217165652.htm (accessed October 22, 2014).

Share This



More Earth & Climate News

Wednesday, October 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

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
How Detroit's Money Woes Led To U.N.-Condemned Water Cutoffs

How Detroit's Money Woes Led To U.N.-Condemned Water Cutoffs

Newsy (Oct. 20, 2014) The United Nations says water is a human right, but should it be free? Detroit has cut off water to residents who can't pay, and the U.N. isn't happy. Video provided by Newsy
Powered by NewsLook.com
Hey, Doc! Sewage, Beer and Food Scraps Can Power Chevrolet’s Bi-Fuel Impala

Hey, Doc! Sewage, Beer and Food Scraps Can Power Chevrolet’s Bi-Fuel Impala

3BL Media (Oct. 20, 2014) Hey, Doc! Sewage, Beer and Food Scraps Can Power Chevrolet’s Bi-fuel Impala Video provided by 3BL
Powered by NewsLook.com
White Rhino's Death In Kenya Means Just 6 Are Left

White Rhino's Death In Kenya Means Just 6 Are Left

Newsy (Oct. 20, 2014) Suni, a rare northern white rhino at Ol Pejeta Conservancy, died Friday. This, as many media have pointed out, leaves people fearing extinction. Video provided by Newsy
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