Skip to page content
USDA Forest Service

Research & Development Treesearch

Treesearch Home
About Treesearch
Contact Us
Research & Development
Forest Products Lab
International Institute of Tropical Forestry
Pacific Northwest
Pacific Southwest
Rocky Mountain
Southern Research Station
Help - We Participate  Government Made Easy

Global Forest Information Service

US Forest Service
P.O. Box 96090
Washington, D.C.

(202) 205-8333

You are here: Home / Search / Publication Information
Bookmark and Share

Publication Information

View PDF (694 KB)

Title: The missing mountain water: Slower westerlies decrease orographic enhancement in the Pacific Northwest USA

Author: Luce, C. H.; Abatzoglou, J. T.; Holden, Z. A.;

Date: 2013

Source: Science. 342: 1360-1364.

Publication Series: Scientific Journal (JRNL)

Description: Trends in streamflow timing and volume in the Pacific Northwest United States have been attributed to increased temperatures because trends in precipitation at lower elevation stations were negligible. We demonstrate that observed streamflow declines likely are associated with declines in mountain precipitation, revealing previously unexplored differential trends. Lower-troposphere winter (November-March) westerlies are strongly correlated to high elevation precipitation but weakly correlated with low elevation precipitation. Decreases in lower-tropospheric winter westerlies across the region from 1950-2012 are hypothesized to have reduced orographic precipitation enhancement, yielding differential trends in precipitation across elevations and contributing to the decline in annual streamflow. Climate projections show weakened lower troposphere zonal flow across the region under enhanced greenhouse forcing, highlighting an additional stressor relevant for climate change impacts on hydrology.

Keywords: streamflow timing, mountain precipitation, climate change, hydrology

Publication Notes:

  • We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
  • This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.



Luce, C. H.; Abatzoglou, J. T.; Holden, Z. A. 2013. The missing mountain water: Slower westerlies decrease orographic enhancement in the Pacific Northwest USA. Science. 342: 1360-1364.


 [ Get Acrobat ]  Get the latest version of the Adobe Acrobat reader or Acrobat Reader for Windows with Search and Accessibility

USDA logo which links to the department's national site. Forest Service logo which links to the agency's national site.