title: Human-induced changes in the hydrology of the western United States.
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.
authors.affiliation: Scripps Institution of Oceanography, University of California, San Diego, La Jolla, CA 92093, USA. tbarnett-ul@ucsd.edu
authors.forename: Tim P
authors.initials: TP
authors.lastname: Barnett
authors.forename: David W
authors.initials: DW
authors.lastname: Pierce
authors.forename: Hugo G
authors.initials: HG
authors.lastname: Hidalgo
authors.forename: Celine
authors.initials: C
authors.lastname: Bonfils
authors.forename: Benjamin D
authors.initials: BD
authors.lastname: Santer
authors.forename: Tapash
authors.initials: T
authors.lastname: Das
authors.forename: Govindasamy
authors.initials: G
authors.lastname: Bala
authors.forename: Andrew W
authors.initials: AW
authors.lastname: Wood
authors.forename: Toru
authors.initials: T
authors.lastname: Nozawa
authors.forename: Arthur A
authors.initials: AA
authors.lastname: Mirin
authors.forename: Daniel R
authors.initials: DR
authors.lastname: Cayan
authors.forename: Michael D
authors.initials: MD
authors.lastname: Dettinger