Skip to Main Content
Declining annual streamflow distributions in the Pacific Northwest United States, 1948-2006Author(s): C. H. Luce; Z. A. Holden
Source: Geophysical Research Letters. 36: L16401. doi:10.1029/2009GL039407. 6 p.
Publication Series: Scientific Journal (JRNL)
Station: Rocky Mountain Research Station
View PDF (312.31 KB)
DescriptionMuch of the discussion on climate change and water in the western United States centers on decreased snowpack and earlier spring runoff. Although increasing variability in annual flows has been noted, the nature of those changes is largely unexplored. We tested for trends in the distribution of annual runoff using quantile regression at 43 gages in the Pacific Northwest. Seventy-two percent of the stations showed significant (a = 0.10) declines in the 25th percentile annual flow, with half of the stations exceeding a 29% decline and a maximum decline of 47% between 1948 and 2006. Fewer stations showed statistically significant declines in either median or mean annual flow, and only five had a significant change in the 75th percentile, demonstrating that increases in variance result primarily from a trend of increasing dryness in dry years. The asymmetric trends in streamflow distributions have implications for water management and ecology well beyond those of shifted timing alone, affect both rain and snow-dominated watersheds, and contribute to earlier timing trends in highelevation watersheds.
- You may send email to email@example.com to request a hard copy of this publication.
- (Please specify exactly which publication you are requesting and your mailing address.)
- 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.
CitationLuce, C. H.; Holden, Z. A. 2009. Declining annual streamflow distributions in the Pacific Northwest United States, 1948-2006. Geophysical Research Letters. 36: L16401. doi:10.1029/2009GL039407. 6 p.
Keywordsstreamflow distributions, water management, watersheds, climate change, Pacific Northwest
- Trends and sensitivities of low streamflow extremes to discharge timing and magnitude in Pacific Northwest mountain streams
- Physical hydrology and the effects of forest harvesting in the Pacific Northwest: a review.
- Wildfire extent and severity correlated with annual streamflow distribution and timing in the Pacific Northwest, USA (1984-2005)
XML: View XML