New Climate Extremes in the Columbia Basin Summary Report

As part of the Columbia Basin Trust's Communities Adapting to Climate Change Initiative, the Pacific Climate Impacts Consortium recently undertook a regional assessment of climate extremes in the Columbia Basin. This assessment used regional climate models (RCMs) to examine how climate extremes may change in the Columbia Basin. The results of this assessment have now been distilled into a summary report.

The project was divided into two parts. In the first part, the RCMs were driven using observation-based data products and their output was compared to observational data, in order to determine how well the RCMs could represent temperature and precipitation, both annually and seasonally. In the second part, the RCMs were driven using the output of global climate models in order to make projections of climate extremes for the 2050s in the Columbia Basin. The models assumed a roughly business-as-usual approach to greenhouse gas emissions.

The RCMs reproduced the climate quite accurately, but do exhibit both cold and wet biases relative to observations. RCM projections showed increases in all basin-average temperature extremes that were analyzed. The projections also indicate an increase in the basin-averaged precipitation and an increase in the frequency of extreme precipitation events over the region as a whole.

The Climate Extremes in the Columbia Basin Summary report provides a brief summary of, and context for, the findings of our regional assessment.  For further details, read the full Preliminary Assessment Report.