1. Colorado’s Water Future Taryn Finnessey Climate Change Risk Management Specialist Colorado Water Conservation Board W/ slides from Jeff Lukas, WWA May 20, 2015 Special Districts Association

3. Severe Drought Colorado has a variable climate…

5. Modified from Figure 2-9 Western Slope April 1 SWE: overall low since 2000, but 30-yr, 50-yr, 70-year trends not significant 0 20 40 60 80 100 120 140 160 180 200 1935194019451950195519601965197019751980198519901995200020052010 % of 1981-2010 average Colorado San Juan Gunnison Yampa- White Observed

6. Colorado Statewide Annual Temperature, 1900–2012

7. Statewide summer Palmer Drought Index (PDSI): significant trend towards more drought in past 30 years http://wwa.colorado.edu Figure 2-11 Observed

8. Long-term observed statewide climate trends April 1 SWEno significant trends Annual streamflow no significant trends Snowmeltearlier Peak runoff timing earlier Palmer Drought Index more drought Heavy precipitation eventsno significant trends Floodsno trends? Observed Heat waves more frequent Cold wavesless frequent Frost-free seasonlonger

9. Figure 5-2 By 2050, typical year will be warmer than the warmest years of the past century Projected

10. Figure 5-4 Any future change in annual precipitation will be difficult to detect as such against the high variability Projected

11. Projected streamflows for Colorado near Cameo (30-year running averages): Broader range of possible futures vs. historical Figure 5-15 Projected

12. Figure 5-16 Observed vs. projected monthly runoff, Colorado near Cameo Projected

13. Summary - Projected climate and hydrology changes Annual streamflow decreases in majority of projections Peak runoff timingearlier in all projections Crop water useincreases April 1 snowpackdecreases in most projections Palmer Drought Index more drought Heat waves more frequent Cold wavesless frequent Frost-free seasonlonger Wildfiresmore frequent Projected

14. Role of Climate Variability in Long Term Water Planning Statewide Water Supply Initiative 2016 & The Colorado Water Plan

15. Projected Depleted Flows for 2050 (acre-feet/year)

16. Questions ? Taryn Finnessey Taryn.Finnessey@state.co.us Climate Change Risk Management Specialist