Anticipating Future Impacts of Temperature on Streamflow in the Colorado River Basin

Principal Investigator

Connie Woodhouse

Start Date

2014-09-01

End Date

2020-03-31

Release Date

2017

Warming temperatures, clearly documented in instrumental records in the Colorado River basin, are having an impact on the amount of annual streamflow yielded from rain and snow. Warmer temperatures result in less flow than might be anticipated, given the precipitation that has fallen. The goal of this project is to assist water managers in planning for future droughts in the Colorado River basin in two main ways. First, it addresses the need for future drought scenarios for planning. Natural climate variability, that has included droughts, will continue but with the added influence of warmer temperatures. Consequently, droughts of the past are not a reliable baseline for anticipating future drought and their impacts. However, droughts of the past plus warming temperatures can provide scenarios of plausible future droughts that could answer questions such as: “What would Colorado River flow look like if we have a 1950s-like drought today or in the next decade?” This perspective can be extended using reconstructions of precipitation from tree rings for the past 500 years, with warming, to assess the impacts of the longest and most severe droughts of the past five centuries on the Colorado River under today’s warmer temperatures. The second way this study will address the need for better drought information is to more closely examine just what it is about warming temperatures that may influence streamflow. We will use models of streamflow that allow an examination of the basin locations and/or levels of streamflow that may be most vulnerable to warming. This information will help water managers be prepared to anticipate how water resources will be impacted by the range of climatic conditions that are likely to occur in the future. Finally, this project will use similar methods to assess the ecological impacts of drought on the upper Colorado River basin.

ScienceBase WMS

• National and Regional Climate Adaptation Science Centers
• Southwest CASC