1. Seattle City Light Climate Change Analysis 1Dept. of Civil and Env. Engineering, UW 2CSES Climate Impacts Group, UW Se-Yeun Lee 1, Alan F. Hamlet 2,1 Overview of Methods for Producing Hydrologic Scenarios and Summary Results

2.  The Streamflow Sites The Criteria for Site Selection The Sources of Naturalized Streamflow Data  The Climate Change Scenarios  Methods Hydrologic Model Bias Correction  Results Bias corrected Simulated Streamflows Summary of Hydrologic Impacts Outline

3.  Usefulness of the Site for Planning (SCL recommendation)  Contributing Upstream Basin Area Larger than about 500 km 2 (approximately 200 sq mi) 1 Site Selection Criteria 1.Smaller basins are not adequately resolved by the 1/16th degree VIC hydrologic model implementation.

4. Information for Selected Streamflow Sites (Skagit River and Pend Oreille River basins) Site Name VIC ID # VIC Name USGS ID # Basin Area (mi 2 ) The Source & Duration of Observed Naturalized Streamflow Ross Dam6111ROSSL12175000999Seattle City Light (WY 1910-2009) Diablo Dam6018DIABL121765001,125Seattle City Light (WY 1910-2009) Gorge Dam6019GORGE121777001,159Seattle City Light (WY 1910-2009) Cascade River6113CASCA12182500172USGS (WY 1929-2008) Ruby Creek6114RUBYC12174000210USGS (WY 1929-1948) Baker River at Concrete 6112SHANN12193500297 Puget Sound Energy (WY 1960- 2001) Sauk River at Sauk 6020SAUKR12189500714USGS (WY 1929-2008) Skagit River at Mt. Vernon 6021SKAMO122005003,093N/A Pend Oreille River at Box Canyon 6023BOXCA1239650024,900 Modified flow only (BPA) (WY 1928-1999) Pend Oreille River at Boundary Dam 6024BOUND1239860025,200 UW (from 1990 BPA modified flows) (1928-1989)

5. Mote, P.W. and E. P. Salathe Jr., 2010: Future climate in the Pacific Northwest 21 st Century Climate Impacts for the Pacific Northwest Region

6. Seasonal Precipitation Changes for the Pacific Northwest http://cses.washington.edu/db/pdf/wacciach1scenarios642.pdf

7. Matrix of Climate Change Scenarios Downscaling Approach A1B Emissions Scenario B1 Emissions Scenario Hybrid Delta 2020s109 2040s109 2080s109 Transient BCSD* (1950-2098+)77 Delta Method 2020s11 2040s11 2080s11 *Bias-Corrected Statistical Downscaling

8. Snow Model Schematic of VIC Hydrologic Model Sophisticated, fully distributed, physically based hydrologic model Widely used globally in climate change applications 1/16 Degree Resolution (~5km x 6km or ~ 3mi x 4mi) General Model Schematic

9. Quantile-Based Bias Correction VIC Input = 19000 Bias Corrected Output = 10000

10. Blue—Observed Naturalized Flow Red—Bias Adjusted VIC Simulations Evaluation of Historical VIC Simulations for the Skagit River at Ross Dam Streamflow (cfs)

11. Bias corrected Simulated Streamflows vs. Raw Simulated Streamflows Skagit River at Ross Dam

12. Overview of Hydrologic Impacts

13. http://www.hydro.washington.edu/2860/products/sites/?site=6111

14. Snow and Runoff Summary (Ross Dam near Newhalem) Scenario EnsemblesEnsemble MeanHistorical Mean

15. http://www.hydro.washington.edu/2860/products/sites/?site=6024

16. Snow and Runoff Summary (Pend Oreille River at Boundary Dam) Scenario EnsemblesEnsemble MeanHistorical Mean

17. Change in Dominant Run-off Behavior Ross DamBoundary Dam

18. Questions? Ross Dam during the Skagit River floods of 2003 (source:http://en.wikipedia.org/wiki/Ross_Dam).