The Climate Change Impacts Assessment

Evaluating Washington’s Future in a Changing Climate ......

A report by The Climate Impacts Group University of Washington

Climate Science June 2009 in the Public Interest Recommended citation: Climate Impacts Group, 2009. The Washington Climate Change Impacts Assessment, M. McGuire Elsner, J. Littell, and L Whitely Binder (eds). Center for Science in the Earth System, Joint Institute for the Study of the Atmosphere and Oceans, University of Washington, Seattle, Washington. Available at: http://www.cses.washington.edu/db/pdf/wacciareport681.pdf

Front cover satellite image credit: http://visibleearth.nasa.gov/view_rec.php?vev1id=4786 NASA - National Aeronautics and Space Administration Visible Earth: A catalog of NASA images and animations of our home planet

Provided by the SeaWiFS Project, NASA/Goddard Space Flight Center, and ORBIMAGE

The Pacifc Northwest is cloud-free in this SeaWiFS image. Multihued phytoplankton blooms are visible of of Washington's Olympic coast. Also visible in this image are: Fraser River outfow, snowcapped peaks of Mt. Olympus, Mt. Rainier, Mt. Adams, Mt. Hood, Mt. Jeferson, the Three Sisters, the North Cascades, and the Columbia and Snake River watersheds.

Metadata * Sensor OrbView-2/SeaWiFS * Visualization Date 2000-09-26 * The Visible Earth is part of the EOS Project Science Ofce located at NASA Goddard Space Flight Center.

Small images credits: Wheat: © 2009 www.photos.com Coast; Seattle skyline: © J. Martin Grassley McNary Dam: courtesy Bonneville Power Administration Salmon: courtesy University of Washington News and Information Forest: courtesy Climate Impacts Group, University of Washington

Report design: Beth Tully, Edit-Design Center, University of Washington The Washington Climate Change Impacts Assessment

Evaluating Washington’s Future in a Changing Climate ......

A report by The Climate Impacts Group University of Washington June 2009

Edited by: Marketa McGuire Elsner Jeremy Littell Lara Whitely Binder

WACCIA Executive Summary iii PRINCIPAL INVESTIGATORS: Edward L. Miles, Director, Climate Impacts Group and Bloedel Professor of Marine Studies and Public Affairs, School of Marine Affairs, University of Washington Dennis P. Lettenmaier, Professor, Dept. of Civil and Environmental Engineering, University of Washington TEAM MEMBERS: Jeremy Avise, Atmospheric Modeling and Support Section, California Air Resources Board Derek B. Booth, Stillwater Sciences and Dept. of Civil and Environmental Engineering, University of Washington Rick Boydston, USDA-ARS, Washington State University IAREC Jay Brunner, Tree Fruit Research and Extension Center, Washington State University Jeff Burkey, King County Water and Land Resources Division Jack Chen, Institute for Chemical Process and Environmental Technology, National Research Council Canada Serena H. Chung, Laboratory for Atmospheric Research, Dept. of Civil and Environmental Engineering, Washington State University Lan Cuo, Dept. of Civil and Environmental Engineering, University of Washington Meriel Darzen, Kathy and Steve Berman Environmental Law Clinic, University of Washington Jeffrey S. Deems, Dept. of Civil and Environmental Engineering, University of Washington Karen Dyson, School of Marine Affairs, University of Washington Marketa McGuire Elsner, Climate Impacts Group, University of Washington Richard A. Fenske, Environmental & Occupational Health Sciences, University of Washington Cole Fitzpatrick, Environmental & Occupational Health Sciences, University of Washington Thomas F. Graham, Kathy and Steve Berman Environmental Law Clinic, University of Washington Gary Grove, Irrigated Agricultural Research and Extension Center, Washington State University Alan F. Hamlet, Climate Impacts Group and Dept. of Civil and Environmental Engineering, University of Washington David Hartley, Northwest Hydraulic Consultants Marc J. Hershman, School of Marine Affairs, University of Washington (in memoriam) Stewart Higgins, Dept. of Biological Systems Engineering, Washington State University Jeffrey A. Hicke, Dept. of Geography, University of Idaho John Hodges-Howell, Kathy and Steve Berman Environmental Law Clinic, University of Washington Daniel D. Huppert, School of Marine Affairs, University of Washington J. Elizabeth Jackson, Dept. of Family Medicine and Dept. of Sociology, University of Washington Catherine Karr, Dept. of Pediatrics and Environmental & Occupational Health Sciences, University of Washington Patrick W. Keys, Dept. of Civil and Environmental Engineering, University of Washington Jennifer Krencicki Barcelos, Kathy and Steve Berman Environmental Law Clinic, University of Washington Chad Kruger, Center for Sustaining Agriculture & Natural Resources, Washington State University Brian K. Lamb, Laboratory for Atmospheric Research, Dept. of Civil and Environmental Engineering, Washington State University Se-Yeun Lee, Dept. of Civil and Environmental Engineering, University of Washington Dennis P. Lettenmaier, Dept. of Civil and Environmental Engineering, University of Washington L. Ruby Leung, Atmospheric Sciences and Global Change Division, Pacifc Northwest National Laboratory Jeremy S. Littell, Climate Impacts Group, University of Washington James A. Lutz, College of Forest Resources, University of Washington Nathan Mantua, Climate Impacts Group and School of Aquatic and Fishery Sciences, University of Washington Jennifer Marlow, Kathy and Steve Berman Environmental Law Clinic, University of Washington Don McKenzie, Climate Impacts Group and USDA Forest Service Pacifc Northwest Research Station Kristian E.B. Mickelson, Dept. of Civil and Environmental Engineering, University of Washington Edward L. Miles, Climate Impacts Group and School of Marine Affairs, University of Washington Amber Moore, School of Marine Affairs, University of Washington Philip W. Mote, Climate Impacts Group and Offce of the Washington State Climatologist Roger L. Nelson, Dept. of Biological Systems Engineering, Washington State University Robert A. Norheim, Climate Impacts Group Elaine E. Oneil, Rural Technology Initiative, College of Forest Resources, University of Washington Richard N. Palmer, Dept. of Civil and Environmental Engineering, University of Massachusetts Amherst Austin Polebitski, Dept. of Civil and Environmental Engineering, University of Massachusetts Amherst Yun Qian, Atmospheric Sciences and Global Change Division, Pacifc Northwest National Laboratory Michael Robinson-Dorn, Kathy and Steve Berman Environmental Law Clinic, University of Washington Eric A. Rosenberg, Dept. of Civil and Environmental Engineering, University of Washington Roger A. Rosenblatt, Dept. of Family Medicine, University of Washington Eric P. Salathé, Jr., Climate Impacts Group, University of Washington Michael Scott, Pacifc Northwest National Laboratory Amy K. Snover, Climate Impacts Group, University of Washington Anne C. Steinemann, Dept. of Civil and Environmental Engineering and Evans School of Public Affairs, University of Washington Claudio O. Stöckle, Dept. of Biological Systems Engineering, Washington State University Ingrid Tohver, Climate Impacts Group, University of Washington Julie A. Vano, Dept. of Civil and Environmental Engineering, University of Washington Nathalie Voisin, Dept. of Civil and Environmental Engineering, University of Washington Lara C. Whitely Binder, Climate Impacts Group, University of Washington Mathew Whiting, Irrigated Agricultural Research and Extension Center, Washington State University Michael G. Yost, Environmental & Occupational Health Sciences, University of Washington Yongxin Zhang, Climate Impacts Group, University of Washington iv WACCIA Executive Summary Table of Contents Executive Summary 1 Evaluating Washington’s Future in a Changing Climate 1: Scenarios 21 Future Climate in the Pacifc Northwest 2: Regional Climate Models 45 Regional Climate Model Projections for the State of Washington 3: Hydrology and Water Resources Implications of 21st Century Climate Chang