river water
; runoff
; snow
; article
; climate
; climate change
; desert
; dust
; environmental exposure
; evapotranspiration
; priority journal
; radiative forcing
; river
; soil
; United States
; vegetation
; Climate Change
; Dust
; Environment
; Humans
; Models, Theoretical
; Rivers
; Seasons
; Snow
; Temperature
; Water Movements
英文摘要:
The waters of the Colorado River serve 27 million people in seven states and two countries but are overallocated by more than 10% of the river's historical mean. Climate models project runoff losses of 7-20% from the basin in this century due to human-induced climate change. Recent work has shown however that by the late 1800s, decades prior to allocation of the river's runoff in the 1920s, a fivefold increase in dust loading from anthropogenically disturbed soils in the southwest United States was already decreasing snow albedo and shortening the duration of snow cover by several weeks. The degree to which this increase in radiative forcing by dust in snow has affected timing and magnitude of runoff from the Upper Colorado River Basin (UCRB) is unknown. Hereweuse the Variable Infiltration Capacity model with postdisturbance and predisturbance impacts of dust on albedo to estimate the impact on runoff from the UCRB across 1916-2003. We find that peak runoff at Lees Ferry, Arizona has occurred on average 3 wk earlier under heavier dust loading and that increases in evapotranspiration from earlier exposure of vegetation and soils decreases annual runoff by more than 1.0 billion cubic meters or ∼5% of the annual average. The potential to reduce dust loading through surface stabilization in the deserts and restore more persistent snow cover, slow runoff, and increase water resources in the UCRB may represent an important mitigation opportunity to reduce system management tensions and regional impacts of climate change.
Painter, T.H., Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, United States, Joint Institute for Regional Earth System Science and Engineering, University of California, Los Angeles, CA 90095, United States; Deems, J.S., National Snow and Ice Data Center, Boulder, CO 80309, United States, National Oceanic and Atmospheric Administration Western Water Assessment, Boulder, CO 80309, United States; Belnap, J., United States Geological Survey, Southwest Biological Center, Moab, UT 84532, United States; Hamlet, A.F., University of Washington, Department of Civil and Environmental Engineering, Seattle, WA 98195, United States; Landry, C.C., Center for Snow and Avalanche Studies, Silverton, CO 81433, United States; Udall, B., National Oceanic and Atmospheric Administration Western Water Assessment, Boulder, CO 80309, United States
Recommended Citation:
Painter T.H.,Deems J.S.,Belnap J.,et al. Response of Colorado river runoff to dust radiative forcing in snow[J]. Proceedings of the National Academy of Sciences of the United States of America,2010-01-01,107(40)