Featured Research

from universities, journals, and other organizations

Greater Solar Activity May Bring United States More Gray Days

Date:
July 16, 2001
Source:
NASA/Goddard Space Flight Center--EOS Project Science Office
Summary:
NASA-funded earth science researchers have discovered that during periods of increased solar activity much of the United States becomes cloudier, possibly because the jet stream in the troposphere moves northward causing changes to regional climate patterns.

NASA-funded earth science researchers have discovered that during periods of increased solar activity much of the United States becomes cloudier, possibly because the jet stream in the troposphere moves northward causing changes to regional climate patterns.

The new study supports earlier findings by suggesting there is a relationship between increased cloud cover over the United States and the solar maximum, the most intense stage of activity on the Sun.

Previous studies have shown that during the solar maximum, the jet stream in the Northern Hemisphere moves northward.

The jet stream guides storms and plays an important role in cloudiness, precipitation and storm formation in the United States.

Dr. Petra Udelhofen, a NASA-funded researcher at the Institute for Terrestrial and Planetary Atmospheres at the State University of New York at Stony Brook, is the lead author of a paper that discusses this topic, appearing in the July 1 issue of Geophysical Research Letters.

"Based on these results and because the location of the jet stream influences cloudiness," said Udelhofen, "we suggest that the jet stream plays an important role in linking solar variability and cloud cover."

The jet stream is a ribbon of fast-moving air in the upper troposphere that blows from west to east. Storms beneath the jet stream follow its path. A shift in the jet stream can alter the location of clouds and precipitation across the U.S.

The troposphere is the region of the atmosphere that extends from the Earth's surface out to about 50,000 feet and is the focus of local, regional and global weather research. The stratosphere extends above the troposphere to about 150,000 feet and is the region where the ozone layer is formed.

The Sun's energy output varies over an 11-year cycle, sending more ultraviolet radiation towards the Earth during times of increased activity. While the Sun's total energy output only varies by about one-tenth of one percent between periods of low and high solar activity, the ultraviolet radiation that affects ozone production in the stratosphere can change by more than 10 percent.

Ultraviolet radiation is absorbed in the Earth's stratosphere and creates the protective ozone layer. When the ozone absorbs ultraviolet radiation, it warms the stratosphere, which may affect movement of air in the troposphere where clouds form.

Solar cycle effects of ultraviolet radiation absorption by ozone in the stratosphere, its impact on atmospheric circulation and the location of storm tracks have been the subject of recent Earth Science research.

"Our results show that cloudiness varies on average by about two percent between years of solar maximum and minimum. In most parts of the U.S., cloud cover is slightly greater in years of solar maximum," noted Udelhofen.

Though more investigation is needed to better understand just how changes in the Sun's ultraviolet energy output is linked to atmospheric winds, the study helps people identify potential large-scale mechanisms that affect local and regional climates.

Scientists continue to investigate mechanisms that may link solar variability with weather. These new results support the idea of a link between stratospheric chemistry and meteorology, and support other recent theoretical studies associated with the impact of stratospheric chemistry on climate change and weather.

"It is important for future studies to identify and explain in detail the link between solar variability, ozone, the atmospheric circulation and cloud cover," Udelhofen said.

This research is part of the NASA Earth Science Enterprise program, which is dedicated to understanding how Earth is changing and what consequences these changes have for life on Earth.

More information is available on the Internet at: http://www.gsfc.nasa.gov/topstory/20010712cloudcover.html


Story Source:

The above story is based on materials provided by NASA/Goddard Space Flight Center--EOS Project Science Office. Note: Materials may be edited for content and length.


Cite This Page:

NASA/Goddard Space Flight Center--EOS Project Science Office. "Greater Solar Activity May Bring United States More Gray Days." ScienceDaily. ScienceDaily, 16 July 2001. <www.sciencedaily.com/releases/2001/07/010716112433.htm>.
NASA/Goddard Space Flight Center--EOS Project Science Office. (2001, July 16). Greater Solar Activity May Bring United States More Gray Days. ScienceDaily. Retrieved July 25, 2014 from www.sciencedaily.com/releases/2001/07/010716112433.htm
NASA/Goddard Space Flight Center--EOS Project Science Office. "Greater Solar Activity May Bring United States More Gray Days." ScienceDaily. www.sciencedaily.com/releases/2001/07/010716112433.htm (accessed July 25, 2014).

Share This




More Earth & Climate News

Friday, July 25, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Goma Cheese Brings Whiff of New Hope to DRC

Goma Cheese Brings Whiff of New Hope to DRC

Reuters - Business Video Online (July 24, 2014) The eastern region of the Democratic Republic of Congo, mainly known for conflict and instability, is an unlikely place for the production of fine cheese. But a farm in the village of Masisi, in North Kivu is slowly transforming perceptions of the area. Known simply as Goma cheese, the Congolese version of Dutch gouda has gained popularity through out the region. Ciara Sutton reports. Video provided by Reuters
Powered by NewsLook.com
Bill Gates: Health, Agriculture Key to Africa's Development

Bill Gates: Health, Agriculture Key to Africa's Development

AFP (July 24, 2014) Health and agriculture development are key if African countries are to overcome poverty and grow, US software billionaire Bill Gates said Thursday, as he received an honourary degree in Ethiopia. Duration: 00:36 Video provided by AFP
Powered by NewsLook.com
Higgins Breaks Record at Mt. Washington

Higgins Breaks Record at Mt. Washington

Driving Sports (July 24, 2014) Subaru Rally Team USA drivers David Higgins and Travis Pastrana face off against a global contingent of racers at the annual Mt. Washington Hillclimb in New Hampshire. Includes exclusive in-car footage from Higgins' record attempt. Video provided by Driving Sports
Powered by NewsLook.com
Storm Kills Three, Injures 20 at Virginia Campground

Storm Kills Three, Injures 20 at Virginia Campground

Reuters - US Online Video (July 24, 2014) A likely tornado tears through an eastern Virginia campground, killing three and injuring at least 20. Linda So reports. Video provided by Reuters
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:
from the past week

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