Human-induced changes in the hydrology of the Western United States

T.P. Barnett; D.W. Pierce; H.G. Hidalgo; Celine Bonfils; B.D. Santer; T. Das; G. Bala; A.W. Wood; T. Nozawa; A.A. Mirin; D.R. Cayan; M. D. Dettinger

doi:10.1126/science.1152538

USGS · 70031917

Human-induced changes in the hydrology of the Western United States

T.P. Barnett·D.W. Pierce·H.G. Hidalgo·Celine Bonfils·B.D. Santer·T. Das·G. Bala·A.W. Wood·T. Nozawa·A.A. Mirin·D.R. Cayan·M. D. Dettinger

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Abstract

Observations have shown that the hydrological cycle of the western United States changed significantly over the last half of the 20th century. 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 that up to 60% of the climate-related trends of river flow, winter air temperature, and snow pack between 1950 and 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.

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T.P. Barnett, D.W. Pierce, H.G. Hidalgo, Celine Bonfils, B.D. Santer, T. Das, G. Bala, A.W. Wood, T. Nozawa, A.A. Mirin, D.R. Cayan, M. D. Dettinger. 2008. Human-induced changes in the hydrology of the Western United States. https://doi.org/10.1126/science.1152538

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