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The article presents a study on a regional climate model (RegCM) coupled with the University of Washington (UW) turbulence parameterization. It describes improvements in the coastal and non-coastal climatology of the model along with enhancements in its representation of stratiform clouds. It also notes that the model later known as RegCM-UW is proper to use in regional climate research and ameliorates the creation of the marine boundary layer.

This paper draws on interviews with Washington State Watershed Planning Leads (Planning Leads) and interactions with local watershed planning units to identify factors that may influence the inclusion of climate change in watershed planning efforts in Washington State. These factors include the interest of individual planning unit members in climate change; Planning Lead familiarity with climate impacts; the influence of trust, leadership, and ‘genetic knowledge’ on planning units; and perceptions of strategic gain. The research also identifies aspects of the planning process that may create opportunities for addressing climate impacts in future planning. These aspects include continuation of watershed planning units after plans are developed; commitment to updating watershed plans; recognition of climate impacts in planning documentation; dedicated incentive funding; and the availability of hydrologic modeling tools for assessing hydrologic impacts. Additional types of technical assistance that could support integration of climate impacts are also identified. It is hoped that the insight provided by this analysis will help individuals involved in stakeholder-based watershed planning recognize the various dynamics potentially affecting the inclusion of climate change in watershed planning and in doing so, contribute to the development of planning approaches and tools that will support local efforts to adapt to climate impacts. [ABSTRACT FROM AUTHOR]

The hydrochemistry of mountain lakes is highly conditioned by the chemical composition of atmospheric deposition and by climate characteristics. Consequently these ecosystems have proved to be sensitive to long-term changes in both factors. Climate warming seems to be particularly pronounced in the Alpine region. A reduction of snow cover in space and time, due to less precipitation and higher temperatures, means a greater exposure of rocks and soils in the watersheds, which enhances weathering processes. In this paper we aim to evaluate the possible effect of these processes on long-term changes in the chemistry of alpine lakes. Recent climate changes affecting the study area were investigated through a data series referring to temperature, precipitation, snow depth and duration at some stations in the Ossola Valley. Chemical data of 35 lakes located in the Ossola and Sesia Valleys (Central Alps) were used. Lakes were sampled both in the late summer of 2000 and 2001 in the framework of two European Projects and the results compared with previous data (1984–1987). Two lakes (Boden Superiore and Inferiore, 2343 and 2334 m a.s.l., respectively), located in the northern part of the study area, have been sampled more or less continuously since the late 70s, enabling us to evaluate the trends of the main chemical variables. For lakes lying in catchments with highly soluble rocks, a comparison between the two data sets shows an increase of solute contents in the last few years. This result could be attributed to increased weathering rates due to climate warming. [ABSTRACT FROM AUTHOR]

Persistent midwinter cold air pools produce multiday periods of cold, dreary weather in basins and valleys. Persistent stable stratification leads to the buildup of pollutants and moisture in the pool. Because the pool sometimes has temperatures below freezing while the air above is warmer, freezing precipitation often occurs, with consequent effects on transportation and safety. Forecasting the buildup and breakdown of these cold pools is difficult because the interacting physical mechanisms leading to their formation, maintenance, and destruction have received little study. In this paper, persistent wintertime cold pools in the Columbia River basin of eastern Washington are studied. First a succinct meteorological definition of a cold pool is provided and then a 10-yr database is used to develop a cold pool climatology. This is followed by a detailed examination of two cold pool episodes that were accompanied by fog and stratus using remote and in situ temperature and wind sounding data. The two episodes illustrate many of the physical mechanisms that affect cold pool evolution. In one case, the cold pool was formed by warm air advection above the basin and was destroyed by downslope winds that descended into the southern edge of the basin and progressively displaced the cold air in the basin. In the second case, the cold pool began with a basin temperature inversion on a clear night and strengthened when warm air was advected above the basin by a westerly flow that descended from the Cascade Mountains. The cold pool was nearly destroyed one afternoon by cold air advection aloft and by the growth of a convective boundary layer (CBL) following the partial breakup of the basin stratus. The cold pool restrengthened, however, with nighttime cooling and was destroyed the next afternoon by a growing CBL. [ABSTRACT FROM AUTHOR]

Background: Exposure to excessive heat kills more people than any other weather-related phenomenon, aggravates chronic diseases, and causes direct heat illness. Strong associations between extreme heat and health have been identified through increased mortality and hospitalizations and there is growing evidence demonstrating increased emergency department visits and demand for emergency medical services (EMS). The purpose of this study is to build on an existing regional assessment of mortality and hospitalizations by analyzing EMS demand associated with extreme heat, using calls as a health metric, in King County, Washington (WA), for a 6-year period.Methods: Relative-risk and time series analyses were used to characterize the association between heat and EMS calls for May 1 through September 30 of each year for 2007-2012. Two EMS categories, basic life support (BLS) and advanced life support (ALS), were analyzed for the effects of heat on health outcomes and transportation volume, stratified by age. Extreme heat was model-derived as the 95th (29.7 °C) and 99th (36.7 °C) percentile of average county-wide maximum daily humidex for BLS and ALS calls respectively.Results: Relative-risk analyses revealed an 8 % (95 % CI: 6-9 %) increase in BLS calls, and a 14 % (95 % CI: 9-20 %) increase in ALS calls, on a heat day (29.7 and 36.7 °C humidex, respectively) versus a non-heat day for all ages, all causes. Time series analyses found a 6.6 % increase in BLS calls, and a 3.8 % increase in ALS calls, per unit-humidex increase above the optimum threshold, 40.7 and 39.7 °C humidex respectively. Increases in "no" and "any" transportation were found in both relative risk and time series analyses. Analysis by age category identified significant results for all age groups, with the 15-44 and 45-64 year old age groups showing some of the highest and most frequent increases across health conditions. Multiple specific health conditions were associated with increased risk of an EMS call including abdominal/genito-urinary, alcohol/drug, anaphylaxis/allergy, cardiovascular, metabolic/endocrine, diabetes, neurological, heat illness and dehydration, and psychological conditions.Conclusions: Extreme heat increases the risk of EMS calls in King County, WA, with effects demonstrated in relatively younger populations and more health conditions than those identified in previous analyses. [ABSTRACT FROM AUTHOR]

Regardless of the efforts governments may take to mitigate the impacts of greenhouse gas emissions and other human activities on climate change, the need for society to adapt to climate change is unavoidable. Adapting to the myriad impacts of climate change will require actions at all levels of government. This article focuses on the anticipated impacts of climate change on the Puget Sound region in the northwestern United States as an example of the range of problems climate change will present and of the solutions available to governments and others interested in avoiding or minimizing the adverse impacts of climate change. As a guide for policy-makers, the article offers general principles for formulating climate change adaptation policies, suggestions for changes in decision-making processes that make them more suitable for addressing the unpredictable impacts of climate change, and strategies for adapting to three specific categories of climate change effects: impacts on the hydrologic cycle,sea-level rise, and altered meteorological conditions. The strategies and recommendations analysed in the article can provide a model for climate change adaptation policies, both in the Puget Sound region and more broadly, that are both environmentally protective and socially equitable. [ABSTRACT FROM AUTHOR]

The aging of society is an inescapable trend that some neighborhoods, municipalities, and counties are admitting needs their attention. As the extent of the changes required to become senior friendly, let alone sustainable, are being realized, many communities are experiencing pushback from voters, old-guard city and county staff, and even elected officials. While initially appearing counter-intuitive, if we plan for the aging of society along with four other first-time-ever, equally inescapable trends-peak oil, water scarcity, obesity, and climate change-we come to realize the critical role of the built environment as a common denominator in preparing for a future very different than most of us have anticipated. As such, changes to the built environment that move a community closer to realizing sustainable senior living also contribute to lower energy needs and costs, a smaller carbon footprint, water savings, and an overall healthier population. By focusing on the built environment as the key to sustainable senior living communities, we are able to build more inclusive collaborative work teams, reach out to two underutilized resources in retirees and college and university students, and leverage the planned-for changes in ways that help finance future modifications. Clarified below, these ideas, strategies, and actions are, in the end, described as part of a five-year, ongoing, service learning partnership. [ABSTRACT FROM AUTHOR]

Lee, Se-Yeun, Alan F. Hamlet, Carolyn J. Fitzgerald, and Stephen J. Burges, 2011. Methodology for Developing Flood Rule Curves Conditioned on El Niño-Southern Oscillation Classification. Journal of the American Water Resources Association (JAWRA) 47(1):81-92. DOI: 10.1111/j.1752-1688.2010.00490.x Regional climate varies on interannual and decadal time scales that in turn affect annual streamflows, flood risks, and reservoir storage deficits in mid-summer. However, these variable elements of the climate system are generally not included in water resources operating policies that attempt to preserve a balance between flood risk and other water resources system objectives. A methodology for incorporating El Niño-Southern Oscillation (ENSO) information in designing flood control curves is investigated. An optimization-simulation procedure is used to develop a set of ENSO-conditioned flood control rule curves that relate streamflow forecasts to flood control evacuation requirements. ENSO-conditioned simulated flood risk and storage deficits under current operating policy are used to calibrate a unique objective function for each ENSO classification. Using a case study for the Columbia River Basin, we demonstrate that ENSO-conditioned flood control curves constructed using the optimization-simulation procedure consistently reduce storage deficits at a number of interrelated projects without increasing flood risk. For the Columbia Basin, the overall improvements in reservoir operations are relatively modest, and (in isolation) might not motivate a restructuring of flood control operations. However, the technique is widely applicable to a wide range of water resources systems and/or different climate indices. [ABSTRACT FROM AUTHOR]

Persistent, 10-km-scale gradients in climatological precipitation tied to topography are documented with a finescale rain and snow gauge network in the Matheny Ridge area of the Olympic Mountains of Washington State. Precipitation totals are 50% higher on top of an ∼800-m-high ridge relative to valleys on either side, 10 km distant. Operational fifth-generation Pennsylvania State University–NCAR Mesoscale Model (MM5) runs on a 4-km grid produce similar precipitation patterns with enhanced precipitation over high topography for 6 water years. The performance of the MM5 is compared to the gauge data for 3 wet seasons and for 10 large precipitation events. The cumulative MM5 precipitation forecasts for all seasons and for the sum of all 10 large events compare well with the precipitation measured by the gauges, although some of the individual events are significantly over- or underforecast. This suggests that the MM5 is reproducing the precipitation climatology in the vicinity of the gauges, but that errors for individual events may arise due to inaccurate specification of the incident flow. A computationally simple model of orographic precipitation is shown to reproduce the major features of the event precipitation pattern on the windward side of the range. This simple model can be coupled to landscape evolution models to examine the impact of long-term spatial variability in precipitation on the evolution of topography over thousands to millions of years. [ABSTRACT FROM AUTHOR]

Three lines of evidence indicate that North Cascade (Washington, USA) glaciers are currently in a state of disequilibrium. First, annual balance measured on nine glaciers yields a mean cumulative balance for the 1984–2004 period of −8·58 m water equivalent (w.e.), a net loss of ice thickness exceeding 9·5 m. This is a significant loss for glaciers that average 30–50 m in thickness, representing 18–32% of their entire volume.Second, longitudinal profiles completed in 1984 and 2002 on 12 North Cascade glaciers confirm this volume change indicating a loss of −5·7 to −6·3 m in thickness (5·0–5·6 m w.e.) between 1984 and 2002, agreeing well with the measured cumulative balance of −5·52 m w.e. for the same period. The change in thickness on several glaciers has been equally substantial in the accumulation zone and the ablation zone, indicating that there is no point to which the glacier can retreat to achieve equilibrium. Substantial thinning along the entire length of a glacier is the key indicator that a glacier is in disequilibrium.Third, North Cascade glacier retreat is rapid and ubiquitous. All 47 glaciers monitored are currently undergoing significant retreat or, in the case of four, have disappeared. Two of the glaciers where mass balance observations were begun, Spider Glacier and Lewis Glacier, have disappeared. The retreat since 1984 of eight Mount Baker glaciers that were all advancing in 1975 has averaged 297 m. These observations indicate broad regional continuity in glacial response to climate. Copyright © 2006 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]