Research

Hydrology and Water Resources: Current Research

Characterizing 20th Century Variability and Trends in Streamflow in Unregulated Rivers in the Pacific Northwest

Personnel

• Nathan Mantua, CIG

Background

Because many Pacific Northwest (PNW) rivers drain basins that receive a significant snowpack each winter and spring, snowmelt runoff and subsequent streamflow is likely to show a strong sensitivity to temperature variations at interannual and longer timescales.

The goal of this study is to examine daily streamflow records from unregulated river basins to identify patterns of temperature sensitivity for various streams, with a special focus on the snowmelt and summer low flow periods.

Research Questions

• Are there regionally coherent variations in snowmelt timing for periods of high and low spring/summer temperatures?
• Are there regionally coherent trends in snowmelt timing?
• Are there regional patterns in the onset and duration of the annual summer low flow periods?

Related Work

The Climate Impacts Group is doing related research on 20th century trends in PNW temperature and precipitation (Mote 2003) and snowpack.