Featured Research

from universities, journals, and other organizations

Global Warming -- Real Or Perceived -- Could Strain Water Resources

Date:
June 8, 1998
Source:
University Of Illinois At Urbana-Champaign
Summary:
Midwest water resources could face substantial pressures if projected global warming and rainfall fluctuation occur, say University of Illinois civil engineers who are studying possible agricultural responses, particularly irrigation, to climate change. Their preliminary conclusions suggest that water-use regulations may need revision.

CHAMPAIGN, Ill. -- Midwest water resources could face substantial pressures if projected global warming and rainfall fluctuation occur, say University of Illinois civil engineers who are studying possible agricultural responses, particularly irrigation, to climate change. Their preliminary conclusions suggest that water-use regulations may need revision.

The potential for varying rainfall could lead to a perceived threat among farmers, who would be tempted to use the irrigation equipment that they installed to recoup their investment when conditions only marginally dictate a benefit, says J. Wayland Eheart, a professor of environmental systems.

Such over-irrigation could reduce stream flow, critically affecting water quality and aquatic ecosystems such as fish populations, adds Edwin E. Herricks, a professor of environmental biology.

Eheart and Herricks are co-investigators of a three-year study funded by the U.S. Environmental Protection Agency to explore the vulnerability of Midwest water resources and aquatic ecosystems. They spoke during a symposium May 19 at the U. of I. Eheart also will chair a June 9 conference on "Water Management Programs for Humid Regions" sponsored by the American Society of Civil Engineers at the Hyatt Regency Hotel in Chicago.

The United Nations' Intergovernmental Panel on Climate Change in 1995 predicted an increase of global mean surface temperature of 1 to 3.5 degrees Celsius by 2100 and increased variances of precipitation in North America because of carbon dioxide emissions. Eheart and Herricks are using historical records of the Sangamon River watershed in Illinois and creating models of potential scenarios.

"The increase in variability of precipitation alone, without a change in mean precipitation, may increase irrigation and, in turn, decrease stream flows," Eheart said. "There is also the Chicken Little effect -- by which even perceived changes could lead to the same result."

Irrigation decisions are assumed in the model to be based on a "root-zone deficit trigger" -- the level of moisture deficit in top soil. Eheart's model adjusts for a variety of conditions and seeks an optimal trigger for using irrigation to assure desirable yields or to maximize profit.

Based on current corn prices, for example, irrigation likely would be used if annual precipitation averages decreased by 15 percent, Eheart said, resulting in the use of more than 4 inches of water -- an amount that is 50 percent of the mean annual groundwater recharge in some parts of the Midwest. In Illinois, as in some other Midwest states, farmers may withdraw water as they please from streams, although they can not install permanent pumping structures.

Over-irrigation could drive stream flows below the traditional minimum dilution flow, at which point waste being discharged is not diluted sufficiently to sustain water-quality standards. Under their model, Eheart said, "we could see up to 60 days per year of violating this standard, depending on the profit- or yield-maximizing strategies farmers choose to use."


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. "Global Warming -- Real Or Perceived -- Could Strain Water Resources." ScienceDaily. ScienceDaily, 8 June 1998. <www.sciencedaily.com/releases/1998/06/980608053534.htm>.
University Of Illinois At Urbana-Champaign. (1998, June 8). Global Warming -- Real Or Perceived -- Could Strain Water Resources. ScienceDaily. Retrieved July 25, 2014 from www.sciencedaily.com/releases/1998/06/980608053534.htm
University Of Illinois At Urbana-Champaign. "Global Warming -- Real Or Perceived -- Could Strain Water Resources." ScienceDaily. www.sciencedaily.com/releases/1998/06/980608053534.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