Observed Spatiotemporal Changes in the Mechanisms of Extreme Water Available for Runoff in the Western United States

Abstract

This paper presents the first study to identity, in historical records, regional changes in the mechanisms of extreme water available for runoff (W). We used a quality‐controlled Snowpack Telemetry data set (1979–2017) combined with the nonparametric regional Kendall test to examine changes in annual maximum W under four hydrometeorological conditions (melt only/rain‐on‐snow/all melt/all melt plus rainfall) over the mountainous regions of the western United States. Under a warming climate, our analyses indicated significant declining trends in annual maximum W at regional scale under all four conditions. The annual maximum of all melt plus rainfall decreased significantly by 15% in the southwestern United States, while the frequency of rain‐on‐snow events increased significantly by 32% in the northwestern United States. The annual maximum snowmelt only decreased significantly by 21% across the entire western United States. Our results confirmed that interaction between regional humidity and solar radiation with warming temperature helps drive these changes.

Document Details

Document Type
Pub Defense Publication
Publication Date
Jan 24, 2019
Source ID
10.1029/2018gl080260

Entities

People

  • André Coleman
  • Hongxiang Yan
  • L. Ruby Leung
  • Mark S. Wigmosta
  • Ning Sun
  • Richard Skaggs
  • Zhangshuan Hou

Organizations

  • Pacific Northwest National Laboratory
  • Strategic Environmental Research and Development Program
  • United States Department of Energy
  • University of Washington

Tags

Fields of Study

  • Environmental science

Readers

  • Mathematics or Statistics
  • Polar and Arctic Studies
  • Strategic Security Studies