Note to users. If you're seeing this message, it means that your browser cannot find this page's style/presentation instructions -- or possibly that you are using a browser that does not support current Web standards. Find out more about why this message is appearing, and what you can do to make your experience of our site the best it can be.

Published Online January 31, 2008
Science DOI: 10.1126/science.1152538

Reports

Submitted on November 2, 2007
Accepted on January 23, 2008

Human-Induced Changes in the Hydrology of the Western United States

Tim P. Barnett 1*, David W. Pierce 1, Hugo G. Hidalgo 1, Celine Bonfils 2, Benjamin D. Santer 2, Tapash Das 1, Govindasamy Bala 2, Andrew W. Wood 3, Toru Nozawa 4, Arthur A. Mirin 2, Daniel R. Cayan 1, Michael D. Dettinger 1

1 Scripps Institution of Oceanography, University of California, San Diego, La Jolla, CA 92093, USA.
2 Lawrence Livermore National Laboratory, Livermore, CA 94550, USA.
3 Land Surface Hydrology Research Group, Civil and Environmental Engineering, University of Washington, Seattle, WA 98195, USA.
4 National Institute for Environmental Studies, 16-2, Onogawa, Tsukuba, Ibaraki 305-8506, Japan.

* To whom correspondence should be addressed.
Tim P. Barnett , E-mail: tbarnett-ul{at}ucsd.edu

Observations have shown the hydrological cycle of the western U.S. changed significantly over the last half of the twentieth century. Here we present a regional, multivariable climate-change detection and attribution study, using a high-resolution hydrologic model forced by global climate models, focusing on the changes that have already affected this primarily arid region with a large and growing population. The results show up to 60% of the climate related trends of river flow, winter air temperature, and snow pack between 1950-1999 are human-induced. These results are robust to perturbation of study variates and methods. They portend, in conjunction with previous work, a coming crisis in water supply for the western United States.


THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES:
A review of hydrological modelling of basin-scale climate change and urban development impacts.
S. Praskievicz and H. Chang (2009)
Progress in Physical Geography 33, 650-671
   Abstract »    PDF »
Selecting global climate models for regional climate change studies.
D. W. Pierce, T. P. Barnett, B. D. Santer, and P. J. Gleckler (2009)
PNAS 106, 8441-8446
   Abstract »    Full Text »    PDF »
From the Cover: Sustainable water deliveries from the Colorado River in a changing climate.
T. P. Barnett and D. W. Pierce (2009)
PNAS 106, 7334-7338
   Abstract »    Full Text »    PDF »
Climatic change and wetland desiccation cause amphibian decline in Yellowstone National Park.
S. K. McMenamin, E. A. Hadly, and C. K. Wright (2008)
PNAS 105, 16988-16993
   Abstract »    Full Text »    PDF »


To Advertise     Find Products

Science. ISSN 0036-8075 (print), 1095-9203 (online)