We thank Environment Canada and Mary Tyree of the Scripps Institution of Oceanography for providing the Canadian streamflow data. Iris Stewart gratefully acknowledges research support through the Clare Booth Luce Foundation. We also appreciated the helpful comments of three anonymous reviewers on an earlier version of this manuscript.
Aguado, E., Cayan D. , Riddle L. , and Roos M. , 1992: Climatic fluctuations and the timing of west coast streamflow. J. Climate, 5, 1468–1483.
Anderson, J., Chung F. , Anderson M. , Brekke L. , Easton D. , Ejeta M. , Peterson R. , and Snyder R. , 2008: Progress on incorporating climate change into management of California’s water resources. Climatic Change, 87, 91–108, doi:10.1007/s10584-007-9353-1.
Barnett, T., Adam J. , and Lettenmaier D. , 2005: Potential impacts of a warming climate on water availability in snow-dominated regions. Nature, 438, 303–309, doi:10.1038/nature04141.
Bates, B., Kundzewicz Z. , Wu S. , and Palutikof J. , Eds., 2008: Climate change and water. Intergovernmental Panel on Climate Change Tech. Paper 6, 200 pp. [Available online at http://www.ipcc.ch/pdf/technical-papers/climate-change-water-en.pdf.]
Bonfils, C., and Coauthors, 2008: Detection and attribution of temperature changes in the mountainous western United States. J. Climate, 21, 6404–6424.
Cayan, D., Kammerdiener S. , Dettinger M. , Caprio J. , and Peterson D. , 2001: Changes in the onset of spring in the western United States. Bull. Amer. Meteor. Soc., 82, 399–415.
Clow, D. W., 2010: Changes in the timing of snowmelt and streamflow in Colorado: A response to recent warming. J. Climate, 23, 2293–2306.
Daly, C., Gibson W. P. , Taylor G. H. , Johnson G. L. , and Pasteris P. , 2002: A knowledge-based approach to the statistical mapping of climate. Climate Res., 22, 99–113.
Das, T., and Coauthors, 2009: Structure and detectability of trends in hydrological measures over the western United States. J. Hydrometeor., 10, 871–892.
Dettinger, M., 2005: Changes in streamflow timing in the western United States in recent decades. USGS Fact Sheet 2005-3018, 4 pp.
Dettinger, M., and Cayan D. , 1995: Large-scale atmospheric forcing of recent trends towards early snowmelt runoff in California. J. Climate, 8, 606–623.
Hamlet, A. F., and Lettenmaier D. P. , 1999: Columbia River streamflow forecasting based on ENSO and PDO climate signals. J. Water Resour. Plann. Manage., 125, 333–341.
Hamlet, A. F., and Lettenmaier D. P. , 2007: Effects of 20th century warming and climate variability on flood risk in the western U.S. Water Resour. Res., 43, W06427, doi:10.1029/2006WR005099.
Hamlet, A. F., Mote P. W. , Clark M. P. , and Lettenmaier D. P. , 2007: Twentieth-century trends in runoff, evapotranspiration, and soil moisture in the western United States. J. Climate, 20, 1468–1486.
Hunter, T., Tootle G. , and Piechota T. , 2006: Oceanic-atmospheric variability and western U.S. snowfall. Geophys. Res. Lett., 33, L13706, doi:10.1029/2006GL026600.
Jain, S., Hoerling M. , and Eischeid J. , 2005: Decreasing reliability and increasing synchroneity of western North American streamflow. J. Climate, 18, 613–618.
Knowles, N., Dettinger M. D. , and Cayan D. R. , 2006: Trends in snowfall versus rainfall in the western United States. J. Climate, 19, 4545–4559.
Luce, C. H., and Holden Z. A. , 2009: Declining annual streamflow distributions in the Pacific Northwest United States, 1948–2006. Geophys. Res. Lett., 36, L16401, doi:10.1029/2009GL039407.
Mantua, N., Hare S. , Zhang Y. , Wallace J. , and Francis R. , 1997: A Pacific interdecadal climate oscillation with impacts on salmon production. Bull. Amer. Meteor. Soc., 78, 1069–1079.
McCabe, G. J., and Clark M. P. , 2005: Trends and variability in snowmelt runoff in the western United States. J. Hydrometeor., 6, 476–482.
Milliman, J. D., Farnsworth K. L. , Jones P. D. , Xu K. H. , and Smith L. C. , 2008: Climatic and anthropogenic factors affecting river discharge to the global ocean, 1951–2000. Global Planet. Change, 62, 187–194, doi:10.1016/j.gloplacha.2008.03.001.
Mote, P. W., 2003: Trends in temperature and precipitation in the Pacific Northwest during the twentieth century. Northwest Sci., 77, 271–282.
Mote, P. W., Hamlet A. F. , Clark M. P. , and Lettenmaier D. P. , 2005: Declining mountain snowpack in western North America. Bull. Amer. Meteor. Soc., 86, 39–49.
Nigam, S., Barlow M. , and Berbery E. H. , 1999: Analysis links Pacific decadal variability to drought and streamflow in United States. Eos, Trans. Amer. Geophys. Union, 80, 621.
NOAA, cited 2009: 2008 global temperature ties as eighth warmest on record. [Available online at http://www.sciencedaily.com/releases/2009/01/090116163206.htm.]
Pagano, T., and Garen D. , 2005: A recent increase in western U.S. streamflow variability and persistence. J. Hydrometeor., 6, 173–179.
Regonda, S. K., Rajagopalan B. , Clark M. , and Pitlick J. , 2005: Seasonal cycle shifts in hydroclimatology over the western United States. J. Climate, 18, 372–384.
Roos, M., 1991: A trend of decreasing snowmelt runoff in northern California. Proc. 59th Western Snow Conf., Juneau, AK, Western Snow Conference, 29–36.
Stewart, I., Cayan D. , and Dettinger M. , 2004: Changes in snowmelt runoff timing in western North America under a “business as usual” climate change scenario. Climatic Change, 62, 217–232.
Stewart, I., Cayan D. , and Dettinger M. , 2005: Changes toward earlier streamflow timing across western North America. J. Climate, 18, 1136–1155.
Tootle, G., Piechota T. , and Singh A. , 2005: Coupled oceanic-atmospheric variability and U.S. streamflow. Water Resour. Res., 41, W12408, doi:10.1029/2005WR004381.
Viviroli, D., Dürr H. H. , Messerli B. , Meybeck M. , and Weingartner R. , 2007: Mountains of the world, water towers for humanity: Typology, mapping, and global significance. Water Resour. Res., 43, W07447, doi:10.1029/2006WR005653.
Woo, M.-K., and Thorne R. , 2008: Analysis of cold season streamflow response to variability of climate in north-western North America. Hydrol. Res., 39, 257–265.