The Pacific Northwest Climate CIGnal
The Climate Impacts Group (CIG) issues a quarterly electronic newsletter designed to provide updates on regional climate and climate-related research, meetings, and topics of interest to Pacific Northwest (PNW) decision makers and resource managers. The first newsletter was distributed in January 2005.
To subscribe to the newsletter, please visit the CIG's "climateupdate" list serve home page. You can also subscribe to the newsletter by sending a blank email to the following address: email@example.com.
The Pacific Northwest Climate CIGnal
Issue #22, Summer 2010
In this Issue
- PNW Climate Outlook
- PNW Streamflow Forecast Update
- Rapid Transition from Warm ENSO to Cool ENSO Associated with Unusually Wet PNW Winters
- Climate Change Analysis for Seattle City Light Provides Projections with Implications for Dam Operations
- New Climate Justice Center at the UW Law School
- Announcing Washington’s new State Climatologist: Nick Bond
- National Research Council Climate Change Reports: America’s Climate Choices
- The First Comprehensive Synthesis on the Response of Marine Ecosystems to Climate Change
- Funding for Climate Change Impacts Assessments Available through the HUD Grant Program
- CIG Publications
- CIG in the News
The 8 July NOAA El Niño Southern Oscillation (ENSO) diagnostic discussion indicates that "La Niña [cold ENSO] conditions are likely to develop during July-August 2010." At this early point in the ENSO cycle it is difficult to forecast the maximum magnitude of the cold event. Read more on the outlook for the Pacific Northwest...
Current climate forecasts from various climatological agencies predict a transition to cold phase ENSO (La Niña) during the remainder of the summer and possible strengthening by winter, although predictive skill is low at this time of year (a typical ENSO transition period). The low summer predictive skill generates some uncertainty in the six month streamflow forecast because the forecast relies on the short-term climatology. The poor snow pack of this water year will also shape the forecast. Consequently, six-month forecasts indicate that 50% of the Columbia River’s stations and all Snake River stations will have below normal streamflows.
In the Columbia River basin, the stations forecasted to have below normal streamflows (70 to 90% of the mean) are predominantly in the lower reaches and Grand Coulee and Chief Joseph. In retrospect, last year’s forecast for stations along the lower Columbia River wavered between normal and below normal streamflows. A year ago the Dalles station on the lower Columbia showed up to 84% of mean streamflow, whereas current forecast hovers around 73% of the mean. Recent streamflow forecasts for tributaries to the Snake River in Idaho, i.e. Willow Creek, indicate streamflows within 95% of the mean, in contrast to last year’s forecast within 116% of the mean. In general, the six-month forecasts suggest a clear trend of below normal streamflows throughout the Snake River Basin, and normal streamflows for the upper reaches to below normal streamflows for the lower reaches of the Columbia River Basin.
About the Forecasts. 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 web site. These experimental real-time forecasts are updated twice monthly (1st and the 15th) and are based on several climate forecast methods. A number of products at the web-site are also 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 that offers daily updates of hydrologic conditions throughout the U.S., can be found on the UW Experimental Surface Water Monitor web site. The Surface Water Monitor shows daily updating estimates of hydrologic conditions throughout the U.S. The site also offers weekly projections for soil moisture and runoff across the U.S. for lead times up to 3 months.
Connections between Pacific Northwest winter climate and the El Niño Southern Oscillation (ENSO) are now well established. In general, warm phases of ENSO (El Niño) increase the odds for warmer and drier winters in the PNW while cool phase ENSOs (La Niñas) increase the odds for cooler and wetter winters. These shifts in average winter conditions can impact water supply, flood risk, skiing, and wildfire risk, among other things (Mote et al. 2003; Hamlet and Lettenmaier 2007). As we look to winter 2010-11, it is worth noting that the transition from one ENSO state to another may also influence the nature of ENSO-related impacts.
ENSO was in the warm phase (El Niño) in the winter of 2009-2010 but has made a rapid transition from warm to cool phase conditions. Figure 1 shows the European Center’s Nino3.4 Index (a measure of ENSO intensity) forecast for the 2010-2011, and NOAA’s Climate Prediction Center and the IRI are also now noting the high likelihood for La Niña conditions in the next few seasons. The central tendency of the ECMWF forecast ensemble shows the Nino3.4 index about -1 degree Celsius by December 2010, solidly in La Niña territory for the coming winter. Although uncertainty is present in current ENSO forecasts, there is relatively high confidence that La Niña conditions will exist for the next few seasons, and the PNW region can expect increased odds for below average temperature and above average precipitation for Oct-March in 2010-2011.
Figure 1 Nino3.4 forecast from the European Center for Medium Range Weather Forecasts. (from European Centre for Medium-Range Weather Forecasts).
Historically, a transition from warm phase ENSO to cool phase ENSO in a single year has produced unusually wet PNW winters with surprising reliability. Table 1, for example, shows warm season (April-September) naturalized flows in the Columbia River at The Dalles, OR (strongly associated with cool season (Oct-March) precipitation and April 1st snowpack over the entire PNW) for a group of historical water years in which 1) the winter season of the water year was cool ENSO, and 2) the previous winter was warm ENSO.
All but one year in the group had above average warm season flow, twelve of fifteen years more than 0.39 standard deviations above the mean. Furthermore some of the wettest years on record are included in this group of water years. WY 1996, for example, was associated with severe flooding throughout the Columbia basin, and WY 1999 produced an immense snowpack (including world record snowfall at Mount Baker of 95 feet) and widespread winter flooding. WY 1974 produced the highest summer flow in the 20th century (challenged only by WY 1997, in second place).
|Water Year||Average April-Sep Flow (cfs)||Anomaly (cfs)||Std. Anomaly (no. standard deviations from mean)|
*Naturalized streamflow data for WY 2008 was not available at the time of this writing, but warm season flow was slightly above average.
Recent research suggests that rapid transitions from warm to cool phase ENSO may be predictable with long lead times under certain conditions based on observational evidence that strong warm phase ENSO events (a Nino3.4 anomaly of more than one standard deviation, or about +1° C) are followed by cool phase ENSO events in 8 out of 11 historical events since 1948 (Okumura and Deser 2010). The implication for water supply forecasting is that a strong warm phase event in one year increases the odds of a rapid shift to a cool phase event in the following year, which provides potential predictability of very high flow in that 2nd year (as above). Thus in June of 1997, with a strong warm phase event clearly established, increased odds of very wet conditions in 1998-1999 would have been predicted in the PNW, a lead time for summer streamflow prediction of about 24 months. Such forecasts may have important implications for power marketing, irrigated agriculture, and other water resources applications.
Although a comprehensive physical explanation for these observed patterns of variability has not yet been established, if you were thinking of getting your roof replaced or buying a full season ski pass, it looks like 2010-2011 might be a good year to do it!
Authors: Alan F. Hamlet, Nate Mantua, Todd Mitchell, CIG
4. Climate Change Analysis for Seattle City Light Provides Projections with Implications for Dam Operations
In a collaborative effort, the CIG recently provided Seattle City Light with projections of climate and stream conditions for the 21st century. This information will support decisions about the management of SCL’s hydroelectric operations and future electricity loads on the Skagit and the Pend Orielle Rivers. The data includes detailed projections of hourly forecasts for the Seattle area, analyses of extreme events for the Skagit basin, streamflow projections, shifts in extreme flow magnitudes, and stream temperature projections for fish habitat surveys. A few of the overall results from this study indicate the following:
- The number of days that temperatures exceed the baseline maximum temperatures (1970-1999) is projected to steadily increase by the mid-21st century. Similarly, there will be fewer days when the daily minimum temperatures typical of the 20th century will occur in the 21st century.
- Changes in the timing and magnitude of peak and low flows were estimated under various future climate change scenarios. For several sites on the Skagit River, the flood magnitude projections intensify late in the 21st century, whereas the extreme low flow projections respond earlier. This is likely attributed to the earlier timing and declining contribution of snowmelt as temperatures warm in the future.
- Stream temperatures are also projected to rise with warmer future air temperatures, provoking negative effects for salmon habitat.
The full report is available in the CIG publication database.
The University of Washington’s School of Law has instituted the climate justice project, Three Degrees, as an enduring center addressing human rights concerns connected with climate change. Three Degrees is a multidisciplinary think tank where scholars, scientists, and professionals come together to advance the field of climate justice. One of the first of its kind in the U.S, Three Degrees works to empower climate-impacted communities around the world to seek necessary compensation for climate harms related to health, food and water, security, equity, and justice. The program does this by (among other things) using independent and applied research to:
- Connect impacted communities with a powerful network of scientists, lawyers, NGOs, and policy makers, helping them build the valuable partnerships that will further legal cases; and
- Coach communities on ways to bring funding priorities before the proper institutional audiences, so that they may secure immediate funding to support their adaptation needs.
Unique challenges posed by cases are brought before the interdisciplinary think tank at the UW, where innovative solutions are engendered by the dialogue that occurs. The program’s work is currently focused on the high Andes in South America. Current projects also include the Climate Justice Seminar, which brings graduate and professional students from fifteen separate disciplines together at UW to assess adaptation strategies for climate vulnerable communities. The Seminar’s ultimate goal is to work along with climate vulnerable communities to create and leverage climate justice responses that are applicable at three—local, national, and international—levels at once while also creating a new type of multidisciplinary and experiential curriculum for graduate students.
Another project is Simulation Summits™. The Summits gather thought leaders, government officials, and citizens together to seriously consider predicted climate futures and the human and social crises they may cause. Set in the home communities of impacted regions, the summits guide local participants through a fictitious disaster scenario grounded in real climate models that will be produced and peer-reviewed in-house.
More on Three Degrees is available through the program’s website.
Washington State has a new state climatologist, Dr. Nick Bond. Dr. Bond has more than 20 years experience in climate research at the University of Washington and is currently a senior meteorologist at JISAO and affiliate associate professor of atmospheric sciences at UW. Dr. Bond’s current research focuses on climate variability and the responses of marine ecosystems, predominantly near Alaska, to atmospheric characteristics. As State Climatologist, Dr. Bond will be involved in supporting research to enhance understanding of conditions that drive climate and weather events statewide, fostering outreach for students, and providing input for the Office of the State Climatologist website and monthly newsletters. The Office of the State Climatologist was initially funded by NOAA, but has been adopted as an entity within the new College of the Environment. The office benefits from the contributions of Dr. Bond’s assistant, Karin Bumbaco, a research scientist at JISAO, who initiates much of the outreach efforts and facilitates the studies that are crucial to innumerable users and state agencies.
America’s Climate Choices is the name of an ensemble of comprehensive studies, requested by Congress, to investigate climate change in the US and galvanize the effort to formulate a national response. In May National Research Council (NRC), the research unit of the National Academy of Sciences and Engineering, released the first three of the five reports, described below.
- Advancing the Science of Climate Change reports on the overwhelming evidence that climate change is indeed an indisputable phenomenon attributable to largely to human activities and that the threats to human and natural systems are too substantial to tolerate continued inaction. The report recommends the creation of seven interrelated themes to guide climate science research so that it will be useful and applicable to decision makers.
- Limiting the Magnitude of Future Climate Change stresses the importance of reducing greenhouse gas emissions by broadly creating a national “budget” for emissions, which sets clear, attainable limits on domestic emissions over a set period of time.
- Adapting to the Impacts of Climate Change emphasizes that the nation must consider the impacts that are unavoidable by managing systems to reduce vulnerabilities. Some of these impacts include sea level rise and more frequent and intense heat waves among other extreme weather events. The report points out that although many of the responses will be local or regional in scale, a national policy must be in place to boost the adaptive capacity regionally and facilitate collaboration among government and non-governmental agencies.
The final two reports in this suite of five are forthcoming later this year. The fourth report, Informing an Effective Response to Climate Change, will be aimed at providing information for decision makers. A final umbrella report will build upon the previous reports to present the scientific framework for making informed decisions.
A recent article published in Science, “The Impact of Climate Change on the World’s Marine Ecosystems,” presents a sweeping review of how climate change is affecting the world’s oceans. Among the recent changes recorded in the oceans are a declining pH (increasing acidity), rising temperatures, and decreasing oxygen content in the upper layers. These changes vary based on latitude (for example the polar oceans are warming faster than the equatorial ocean) and on depth (Figure 2). Such discrepancies are important drivers of local circulation dynamics, climate and biology.
Figure 2 Recent changes in ocean temperature, acidity and carbonate ion concentration (from O. Hoegh-Guldberg et al. (2010)).
The large-scale chemical and physical changes in the oceans have provoked broad biological responses. For example, rising temperatures are proven to increase metabolic rates, however if temperatures exceed optimal ranges, organisms can undergo thermal stress and increased mortality rates. The increase in acidity, temperature and stratification of the waters reduces primary productivity, and this trend is more prevalent in higher latitudes. The implications of less productive oceans cascade through the entire marine food chain, and even threaten the ability of phytoplankton to continually uptake atmospheric carbon.
The paper concludes by emphasizing that the ocean is a tremendous source of uncertainty, not only in terms of its ecosystems and organisms but also in regard to its role in the global carbon cycle. Thus it is imperative to continue marine research, enhance our understanding and create flexible policies to address the range of changes.
The U.S. Department of Housing and Urban Development (HUD), under the Sustainable Communities Regional Planning Grant Program, has announced the availability of funds to support metropolitan and multijurisdictional planning efforts that integrate housing, land use, economic and workforce development, transportation, and infrastructure investments to address the interdependent challenges of: (1) economic competitiveness and revitalization; (2) social equity, inclusion, and access to opportunity; (3) energy use and climate change; and (4) public health and environmental impact. A major focus of the grant is development of a comprehensive Regional Plan for Sustainable Development (RPSD). Eligible activities under the grant include climate change impacts assessments for use in developing the RPSD.
These assessments could broadly evaluate a range of climate change impacts or focus on regional concerns, for instance, sea level rise or water availability. Applications for the grant are due August 23. Please visit the agency’s website for more information.
Recent CIG publications include the following:
Slaughter, R. 2010. Re-allocating water in the Pacific Northwest. In The Water Report 77:16-25.
Slaughter, R., A.F. Hamlet, D.D. Huppert, J. Hamilton, and P.W. Mote. 2010. Re-allocating water in the Pacific Northwest. Mandates vs. markets: Addressing over-allocation of Pacific Northwest river basins. Water Policy 12 (2010) 305–317, doi: 10.2166/wp.2009.152.
Snover, A.K., A.F. Hamlet, J. Lee, N.J. Mantua, E.P. Salathé, R. Steed, and I. Tohver. 2010. Seattle City Light Climate Change Analysis: Climate change impacts on regional climate, climate extremes, streamflow, water temperature, and hydrologic extremes. Prepared for The City of Seattle, Seattle City Light by The Climate Impacts Group, Center for Science in the Earth System, Joint Institute for the Study of the Atmosphere and Ocean, University of Washington.
Recent media stories featuring CIG research and/or researchers include the following:
- Tribes prepare for impacts of climate change (Indian Country News, June 11)
- It's not just BP's oil in the Gulf that threatens world's oceans (McClatchy, July 4)
- Climate change fuels a desire for action (The Daily Astorian, July 14)
- Sun likely to break up shroud of clouds by midweek (Seattle Times, August 11)
Additional news items are available at CIG in the News.
Posted August 13, 2010