Featured Research

from universities, journals, and other organizations

Land use change influences continental water cycle

Date:
June 28, 2011
Source:
Delft University of Technology
Summary:
Forests, and tropical forests in particular, play an important role in the global water cycle. Scientists have recently shown that evaporation from the Amazon forest is for more than 50% responsible for the rainfall in Peru, Bolivia, Argentina, Uruguay, Paraguay and southern Brazil, where it feeds crops and rivers. Similarly in Africa, the Congo forest exports tons of water through the atmosphere to the West-African countries.

Forests, and tropical forests in particular, play an important role in the global water cycle. Delft University of Technology PhD researcher Ruud van der Ent (TU Delft, The Netherlands) has recently shown that evaporation from the Amazon forest is for more than 50% responsible for the rainfall in Peru, Bolivia, Argentina, Uruguay, Paraguay and southern Brazil, where it feeds crops and rivers. Similarly in Africa, the Congo forest exports tons of water through the atmosphere to the West-African countries.

Van der Ent also shows that land use changes such as irrigation, dams, and deforestation can alter evaporation patterns in a region, potentially affecting water resources in distant regions.

Moisture recycling

With his research, Van der Ent has won the 2011 WMO (World Meteorological Organization) Research Award for Young Scientists. Van der Ent won the WMO prize for his Water Resources Research paper 'Origin and fate of atmospheric moisture over continents', co-authored by Prof. Huub Savenije, Bettina Schaefli en Susan Steele-Dunne (all TU Delft). The paper shows that water falling as precipitation in one region may have originated in a distant region, or that it may be recycled moisture that originated as evaporation within the region. Global wind patterns, topography, and land cover all play a role in moisture recycling patterns and the distribution of global water resources. Land use changes such as irrigation, dams, and deforestation can alter evaporation patterns in a region, potentially affecting water resources in distant regions.

Global perspective

Many studies of moisture recycling have had a regional focus up until now. To provide a global perspective, Van der Ent et al. created global maps showing the sources of atmospheric moisture for various regions. The researchers estimate that on average 40% of terrestrial precipitation originates from land evaporation, and 57% of all terrestrial evaporation returns as precipitation over land. They found that some regions rely on recycled water from within the region, while others get moisture from different regions. For instance, water evaporating from Eurasia is responsible for 80% of China's water resources, and the Rio de la Plata basin in South America gets 70% of its water from evaporation from the Amazon.

Deforestation

Related research by recent TU Delft PhD graduate Miriam Gerrits looked into the way forests evaporate their water to the atmosphere. Gerrits found that forest floors are for a large part responsible for evaporation in forests. Removal of forests will thus not only reduce the evaporation from the trees, but will also reduce the evaporation from the forest floor. The resulting local decrease of evaporation is very likely to have global consequences for rainfall, water resources and food security.


Story Source:

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


Journal Reference:

  1. Rudi J. van der Ent. Origin and fate of atmospheric moisture over continents. Water Resources Research, Vol. 46, W09525, 2010

Cite This Page:

Delft University of Technology. "Land use change influences continental water cycle." ScienceDaily. ScienceDaily, 28 June 2011. <www.sciencedaily.com/releases/2011/06/110628111842.htm>.
Delft University of Technology. (2011, June 28). Land use change influences continental water cycle. ScienceDaily. Retrieved July 23, 2014 from www.sciencedaily.com/releases/2011/06/110628111842.htm
Delft University of Technology. "Land use change influences continental water cycle." ScienceDaily. www.sciencedaily.com/releases/2011/06/110628111842.htm (accessed July 23, 2014).

Share This




More Earth & Climate News

Wednesday, July 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

New Orleans Plans to Recycle Cigarette Butts

New Orleans Plans to Recycle Cigarette Butts

AP (July 21, 2014) New Orleans is the first U.S. city to participate in a large-scale recycling effort for cigarette butts. The city is rolling out dozens of containers for smokers to use when they discard their butts. (July 21) Video provided by AP
Powered by NewsLook.com
Shark Sightings a Big Catch for Cape Tourism

Shark Sightings a Big Catch for Cape Tourism

AP (July 21, 2014) A rise in shark sightings along the shores of Chatham, Massachusetts is driving a surge of eager vacationers to the beach town looking to catch a glimpse of a great white. (July 21) Video provided by AP
Powered by NewsLook.com
Spectacular Lightning Storm Hits London

Spectacular Lightning Storm Hits London

AFP (July 19, 2014) A spectaCular lightning storm struck the UK overnight Friday. Images of lightning strikes over the Shard and Tower Bridge in central London. Duration: 00:23 Video provided by AFP
Powered by NewsLook.com
A Centuries' Old British Tradition Is Far from a Swan Song

A Centuries' Old British Tradition Is Far from a Swan Song

AFP (July 19, 2014) As if it weren't enough that the Queen is the Sovereign of the UK and 15 other Commonwealth realms, she is also the owner of all Britain's unmarked swans. Duration: 02:18 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:
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