1. Pacific Northwest climate outlook

The Climate Prediction Center's outlook for June-July-August is for a greater than 33% chance of warmer than normal temperatures and below normal precipitation for the Pacific Northwest with the exception for Idaho, where there is a 40% chance of below normal precipitation. Read more about the Pacific Northwest outlook.

2. Pacific Northwest streamflow forecast updates

West-wide Seasonal Hydrologic Forecasts Update (Columbia R., Snake R., and other western-U.S. rivers)

Since the last update in mid-March, the Pacific Northwest (PNW) has experienced above-average precipitation in the northern portion of the region, but below-average precipitation to the south and east, particularly in the Snake River basin. As a result, soil moisture now varies from higher than average in the north to lower than average in the south and east.

Snowpack has also varied within the region. Snowpack in the Washington's Cascade Range and southern British Columbia was normal to above normal in Spring 2007 while the rest of the region experienced below normal snowpack levels. The lack of snow in large areas of the PNW has resulted in slightly lower streamflow forecasts for the Columbia River at Dalles, with projections decreasing from 92% of average flow in early February to 88-90% in early June. The continuously drier conditions and below normal snowpack in the Snake River basin have also lowered expected summer streamflow volumes at locations such as Clarkston, WA, where the forecast of 78% of average early in February dropped to 65% in early June.

Graphical depictions of recent estimates of soil moisture, snow water equivalent, and streamflow can be found at the University of Washington's West-wide Seasonal Hydrologic Forecast System website. These experimental real-time forecasts are updated monthly and are based on several climate forecast methods. A number of products at the web-site, however, are now updated on a daily basis. These include basin-averaged water balance conditions for each forecast point, spatial maps of current conditions, and a spatial summary of snow water equivalent for the western U.S.

A related effort, showing daily updates of hydrologic conditions throughout the U.S., can be found on the UW Experimental Surface Water Monitor website. The Surface Water Monitor shows daily updating estimates of hydrologic conditions throughout the U.S. New daily data products include water balance estimates for the Missouri, the upper Rio Grande, and the Arkansas-Red River Basins. Since the website's launch in April 2005, the Surface Water Monitor has increasingly become a data source used by U.S. Drought Monitor and Drought Outlook authors in the preparation of their operational products.

3. Washington State establishes adaptation work groups

Under Executive Order 07-02, the Washington Climate Change Challenge, Washington State Governor Christine Gregoire has tasked the Washington Department of Community, Trade, and Economic Development (CTED) and Department of Ecology (ECY) to determine what steps Washington needs to take to prepare for the impacts of climate change. To accomplish this task, Preparation/Adaptation Working Groups (PAWGs) have been created in five key economic sectors: fresh water, agriculture, public health, coasts and infrastructure, and forests. With the assistance of the Climate Impacts Group, the PAWGs will review the projected climate impacts for each sector and identify key issues/vulnerabilities, specific adaptation measures, and critical research needs. Recommendations to the Directors of CTED and ECY are due from the PAWGs by December 14, 2007 and will be presented to the Governor in February 7, 2008.

4. New Washington State climate impacts assessment planned for 2007-2008

The Climate Impacts Group (CIG), in partnership with Pacific Northwest National Laboratory and Washington State University, is launching a major research effort this summer to develop an updated climate change impacts assessment for Washington State. The $1.5 million effort will focus on seven key areas: water resources, public health, irrigated agriculture, infrastructure, forests, coasts, salmon. Updated climate change scenarios at a range of scales (from state-wide to 15-km grid size) and information on adapting to climate change impacts will also be provided through this work. Funding for the assessment was provided by the Washington State legislature under House Bill 1303 (HB 1303).

HB 1303 asks the CIG to examine how climate change will affect the people and resources of Washington State over the next 50 years. Major deliverables include:

• A report describing how climate change is projected to affect the people and resources of Washington state over the next 50 years, focusing on impacts on water resources, public health, irrigated agriculture, forests, coast lines, and salmon. Where possible, the report will indicate how impacts vary by region across the state and indicate locations of high and low sensitivity to climate change. The report will also characterize barriers to adaptation to these impacts (e.g., legal, institutional) and prioritize areas for future action.
• A web portal providing free access to data and maps indicating projected changes in temperature, precipitation, sea level rise, snowpack, streamflow, agricultural and public health impacts, salmon risk, forest risk, coastal vulnerability.

Work is scheduled to begin in July 2007. An interim report to the Governor will be provided on December 1, 2007 and a final report issued December 15, 2008. More details on the work will be provided in forthcoming issues of the Climate CIGnal.

5. Comprehensive hydrologic climate change scenarios planned for the Columbia River basin

The lack of water planning scenarios that reflect expected changes in 21st century climate has been a formidable obstacle to incorporating climate change information into water planning efforts and policy decisions in the Columbia River basin. To address this shortcoming, the Washington State Department of Ecology is providing funding to the Climate Impacts Group (CIG) to develop comprehensive and publicly available hydrologic climate change scenarios for the Columbia River basin.

The databases created by the CIG will be based on hydrologic simulations produced by the Variable Infiltration Capacity (VIC) macro-scale hydrologic model, which will be implemented at a 1/16th degree (~12.5 sq. mi.) spatial resolution. This implementation scale will double the spatial resolution of the VIC models used in past studies, allowing for a more accurate representation of topographic features in the basin and better assessment of smaller watershed sensitivity to changes in climate.

In addition to the VIC modeling, a fine scale hydrologic model (the Distributed Hydrology Soil Vegetation Model, or DHSVM) will be implemented in four pilot study basins to assess the potential advantages of implementing more costly high resolution models in small-scale watersheds. DHSVM grid sizes are considerably smaller (typically ~0.01 sq. mi., or roughly the size of a city block) than the VIC model grid sizes. The DHSVM runs will also estimate changes in water temperature. The likely pilot study basins are the Methow, Okanogan, Walla Walla, and Yakima River basins. Updates of this research will be available in forthcoming issues of the Climate CIGnal.

6. Modeling the impacts of climate change and land use change on salmon recovery in the Snohomish River basin, Washington

An innovative collaboration between NOAA and the University of Washington evaluated the effects of future climate change and large scale land use changes on Chinook salmon in the Snohomish River basin. This study is significant given the potential for these impacts to affect the basin's $133.7 million salmon recovery plan. The study used changes in temperature and precipitation derived from two climate models to project shifts in streamflow and water temperature in the years 2025 and 2050. The model also accounted for the recovery plan's planned changes in land cover and land use. The outputs from the hydrology and water quality model then served as inputs into a salmon life cycle model that calculated how Chinook salmon might respond to the altered conditions.

The research found that climate change is likely to make it more difficult to reach salmon recovery targets in the Snohomish Basin. In the absence of habitat restoration, Chinook salmon populations (already at 10% of their historic level) are likely to decline by 20-40% by the decade of the 2050s. This decline can be attributed to warmer water temperatures, lower spawning flows, and an increase in the magnitude of winter peak flows. Moderate restoration, defined as the completion of current restoration projects but no further restoration, failed to fully compensate for the impacts of climate change by 2050. Full restoration, on the other hand, resulted in a -5% decline to a +19% increase in mean salmon abundance depending on the climate model evaluated. Full restoration is defined as meeting all restoration targets in the restoration plan. Restoration of juvenile salmon rearing capacity in the lower basin will be particularly important for salmon recovery. More information on the study is available in Battin et al. 2007 and on the CIG's project summary web page.

7. CIG in the news: Recent media stories

Recent media stories featuring CIG research and/or researchers include the following:

• Vulnerability forces areas to face change - San Diego Union-Tribune, June 25, 2007
• Kilimanjaro not a victim of climate change, UW scientist says - The Seattle Times, June 12, 2007
• Study: Kilimanjaro's shrinking snow not sign of warming - CNN.com, June 12, 2007
• Warming clouds national parks - The Chicago Tribune, June 10, 2007
• Climate changes evident in West, experts say - The Olympian, June 7, 2007
• Study to examine climate change within state - KOMO-4 News, May 28, 2007
• Global warming could impact climate, forests and snowpack - The Seattle Times, May 22, 2007
• Snowpack feels the heat of rain above 6,500 feet - The Oregonian, April 25, 2007
• It's time to get serious about climate change - The Seattle Times, April 20, 2007
• Our View: We need more answers to help salmon - The Idaho Statesman, April 10, 2007
• Permanent drought predicted for Southwest - The Los Angeles Times, April 6, 2007
• Global warming could deal big blow to salmon - The Seattle Times, April 6, 2007
• Nickels' watershed view: City's supply OK for now - The Seattle Times, March 29, 2007
• Spring of our discontent - Washington CEO Magazine, March 23, 2007

Additional news items are available at CIG in the News.

8. Recent CIG Publications

Recent CIG publications include the following:

• Battin, J., M.W. Wiley, M.H. Ruckelshaus, R.N. Palmer, E. Korb, K.K. Bartz, and H. Imaki. 2007. Projected impacts of climate change on salmon habitat restoration. Proceedings of the National Academy of Sciences 104(16): 6720–6725.
• Hamlet, A.F., P.W. Mote, M.P. Clark, and D.P. Lettenmaier. 2007. 20th century trends in runoff, evapotranspiration, and soil moisture in the Western U.S. Journal of Climate 20(8): 1468-1486. DOI: 10.1175/JCLI4051.1
• Kaje, Janne H. and Daniel D. Huppert. The value of short-run climate forecasts in managing the coastal coho salmon (Onchohynchus kisutch) fishery in Washington State. Natural Resource Modeling 20(2):321-349.
• Keeton, W.S., P.W. Mote, and J.F. Franklin. 2007. Climate variability, climate change, and western wildfire with implications for the urban-wildland interface. pp. 225-253. In A. Troy and R. Kennedy (eds)., Living on the Edge: Economic, Institutional and Management Perspectives on Wildfire Hazard in the Urban Interface. Advances in the Economics of Environmental Resources, Vol. 6. Oxford, United Kingdom: Elsevier Sciences JAI Press.
• Lemke, P., J. Ren, R.B. Alley, I. Allison, J. Carrasco, G. Flato, Y. Fujii, G. Kaser, P.W. Mote, R.H. Thomas, and T. Zhang. 2007. Observations: Changes in snow, ice and frozen ground. Chapter 4 in S. Solomon, D. Qin, M. Manning, Z. Chen, M. Marquis, K.B. Averyt, M. Tignor and H.L. Miller (eds.), Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA.
• Mote, P. and G. Kaser. 2007. The shrinking glaciers of Kilimanjaro: Can global warming be blamed? American Scientist 94(4): 318-325.
• Petersen, A. 2007. Anticipating sea level rise response in Puget Sound. M.M.A. thesis, School of Marine Affairs, University of Washington, Seattle.
• Slaughter, R., and J.D. Wiener. 2007. Water, adaptation, and property rights on the Snake and Klamath Rivers. Journal of the American Water Resources Association 43(2):308-21. DOI: 10.1111 / j.1752-1688.2007.00024.x.
• Trenberth, K.E., P.D. Jones, P. Ambenje, R. Bojariu, D. Easterling, A. Klein Tank, D. Parker, F. Rahimzadeh, J.A. Renwick, M. Rusticucci, B. Soden, and P. Zhai. 2007. Observations: Surface and atmospheric climate change. Chapter 3 in S. Solomon, D. Qin, M. Manning, Z. Chen, M. Marquis, K.B. Averyt, M. Tignor and H.L. Miller (eds.), Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA. (Contributing author: Philip Mote)

For copies of these papers, please contact the CIG. A complete listing of CIG publications is available on the CSES publications page.