1. Impact of Climate Change on Water Resources: Is it an Issue for Emergency Managers? Richard Palmer Dept. of Civil and Environmental Engineering University of Washington Seattle, Washington 98195 www.tag.washington.edu February 8 th, 200 Talk for Emergency Managers

2. Why Forecast Climate Change Impacts? The future ain't what it used to be.

3. Since the 1950’s we have seen Warmer weather and Variable precipitation Spring Snowpack Is DOWN significantly What has already happened?

5. April 1 SWE at Mt. Gardner Consistent declining trend between observed and simulated April 1 SWE for Mt. Gardner

7. Changes in Annual Spring Flow on the Cedar River above Chester Morse Reservoir, 1949-2003 Fractions of annual flow occurring in March and June on the Cedar River above Chester Morse reservoir. Station Elevation 1560 ft. March June

8. Climate shifts will have significant impacts: summers with less water/more conflicts decrease in ability to produce hydropower late falls and winters with higher streamflows more flooding What could this mean?

9. 100 year event may become 50 or 25 year event increased flooding implies impacts on transportation (closed roads, scour at bridges) increased flooding can harm other infrastructure combined sewer overflows/stormwater Just consider flooding

11. Predictions are for 50 less snowpack by 2040 Who remembers 1987 and 1992? Longer, warmer, dryer summers Outdoor water use curtailments Impacts on fish Just consider water supply

12. Regional warming of 2-4°F by 2040s Reduced winter snowpack and summer streamflow Longer drawdown periods of storage Impacts on water demand, but mediated by changing habits Incorporate climate change into emergency planning considerations Planning for Climate Change

13. During the past 50 years, the region has been warming, snowpack has decreased, the hydrologic regime has shifted Trends are similar for all transitional watersheds, the primary source of municipal water Studies suggest continued warming, lower snowpack, and reduced summer flows These changes will have impacts on both water supply and fish Regional water supply planning should include the impacts of climate change Conclusions

14. Questions?