Typical month of historical flooding events is shown by the colour of the dots in the scatter plot (legend inset in the upper right corner), by permission of I. Tohver, A.F. Blue lines show the average historical values (19162006) (repeated in each panel). Gridded datasets provide full spatial coverage (i.e., all grid cells in the model domain) at monthly time scales, of the key hydroclimatic variables listed in Table 2. Since its inception in 1995, CIG has been extensively involved in climate-related research focused on the CRB and its water resources management systems. Precipitation Regression on Independent Slopes Model (Daly et al., Extreme daily high flow value with a 20-year recurrence interval (20-year flood), Extreme daily high flow value with a 50-year recurrence interval (50-year flood), Extreme daily high flow value with a 100-year recurrence interval (100-year flood), River Management Joint Operating Committee. Other impacts, such as changes in soil moisture dynamics are also apparent in the simulations. A low pressure system slowly moving offshore is forecast to spin moisture into the Columbia Basin Sunday as it meanders closer to the Southern Oregon Coast. By late 21st century, annual precipitation increases by 5% (8%), with an 8% (14%) winter increase and a 4% (10%) summer decrease, but because . Thus, depending on their needs and level of technical sophistication, stakeholders can make the best use of the study products by extracting information at different points in the data processing sequence, all of which are available on the study web site. For climate change studies in the western United States where snow is an important element of the hydrologic cycle, the model's use of a sophisticated energy-balance snow model, which incorporates important effects on snow accumulation and melt associated with vegetation canopy (Andreadis, Storck, & Lettenmaier, Citation2009) has been a notable advantage. An overview of the Columbia Basin Climate Change Scenarios Project: Approach, methods, and summary of key results. YAKIMA Lower Columbia returned to the diamond on Friday with a double-header split against Yakima Valley.
The study was also unique in that this was the first time that these agencies had run their own reservoir operation models to assess climate change impacts in the CRB, an element of the study design which greatly increased the impact of the study conclusions in the agencies involved. During initial model development steps, Elsner et al. The PET increases over most of the PNW in summer as a result of rising temperatures; however, AET is reduced in all but a few areas of the domain because AET is water limited and summer precipitation decreases in the simulations. 1990 level modified streamflow 19281989. (Citation2010) interpolated existing 1/8 degree model parameters to 1/16 degree and also included previously calibrated soil parameters for the Yakima sub-basin (please see acknowledgements). 4 Flow chart illustrating the post-processing steps used to produce the various hydrologic products served on the study website. These results point to extensive, landscape-scale transformations in hydrologic behaviour associated with climate change. Daily and monthly average streamflow for all projections listed in Table 1 and, where possible, daily and monthly bias-corrected streamflow values. (*Modified flows are essentially naturalized flows with a consistent level of consumptive demand for water supply subtracted for the entire time series.). The CRBs cover an area over 87,000 miles 2, with an estimated volume of 50,000 miles 3, and cover about 36 percent of the state. Calibration of the VIC model was carried out using an automated calibration tool called MOCOM-UA developed by the Land Surface Hydrology group at the UW, following the approach described by Yapo, Gupta, and Sorooshian (Citation1998). To learn about our use of cookies and how you can manage your cookie settings, please see our Cookie Policy. Ltude a produit une squence de traitements de donnes de bout en bout, la fine pointe, partant d'une sortie brute de modle climatique pour aboutir une srie de produits de modlisation hydrologique, qui sont offerts la communaut d'utilisateurs via une base de donnes Web. 2013b. These emerging needs ultimately led to the CBCCSP, and similar efforts in BC led by PCIC (Werner, Schnorbus, Shrestha, & Eckstrand, Citation2013). The strategy for model calibration used in the CBCCSP was to calibrate 11 relatively large sub-basins within the domain (Fig. Simulation of spatial variability in snow and frozen soil, A multi-model ensemble approach to assessment of climate change impacts on the hydrology and water resources of the Colorado River basin, CIG (Climate Impacts Group). Lows in the upper 40s to lower 50s. 3. Special thanks also to Dennis P. Lettenmaier, head of the Land Surface Hydrology Group at the UW, for providing access to computer resources and system administration support for the CBCCSP. Act relating to water resource management in the Columbia river basin, H.R. Naturalized streamflow data were used exclusively in the CBCCSP to calibrate the hydrologic model. These areas are so cold in winter (DJF average on the order of -10C temperature) that a change in temperatures of 23C has relatively little effect on seasonal snow accumulation in the 2020s and 2040s. Each product is provided as a gridded file (one file for each variable and calendar month) in ASCII format. Over the last several years, the USFS and USFWS have engaged with the CIG to produce a set of initial climate change hydrologic scenarios over much of the west using a common methodology intended to support landscape-scale assessment of climate change impacts (Littell et al., Citation2011). Les simulations dcoulements de crue et dtiage augmentent en intensit pour la plupart des sites fluviaux compris dans cette tude. The RMJOC is specifically dedicated to reviewing the practices, procedures, and processes of each agency to identify changes that could improve the overall efficiency of the operation and management of the Federal Columbia River Power System projects. Strong bias in the simulations is commonly caused by precipitation errors (too much or too little annual precipitation), or in some cases by substantial errors in base flows because of contributions from groundwater in the actual system, which are not simulated by the VIC model (Wenger, Luce, Hamlet, Isaak, & Neville, Citation2010). Interactive influences of climate change and agriculture on aquatic habitat in a Pacific Northwestern watershed, PROJECTED CLIMATE CHANGES OVER THE MIDWEST AND GREAT LAKES REGION, River Bed Elevation Variability Reflects Sediment Supply, Rather Than Peak Flows, in the Uplands of Washington State, Springs as hydrologic refugia in a changing climate? Agencies at the state and local levels were similarly engaged, two notable examples in the PNW being King County, Washington (Casola et al., Citation2005), and the WDOE, which manages (among many other water-related issues) the state's water resources and water quality permitting programs. The CBCCSP also provided a complete and well-tested data processing sequence for post-processing and summarizing the hydrologic data to provide figures and analysis efficiently. The VIC model has been widely applied in climate change studies at both the regional scale (e.g., Christensen & Lettenmaier, Citation2007; Lettenmaier, Wood, Palmer, Wood, & Stakhiv, Citation1999; Maurer, Citation2007; Maurer & Duffy, Citation2005; Payne et al., Citation2004; Van Rheenen, Wood, Palmer, & Lettenmaier, Citation2004) and global scale (e.g., Adam, Hamlet, & Lettenmaier, Citation2009; Nijssen, O'Donnell, Hamlet, & Lettenmaier, Citation2001). %%EOF
Please note: Selecting permissions does not provide access to the full text of the article, please see our help page Although these ongoing research and outreach efforts had already laid an extensive foundation in support of pilot climate services in the PNW, starting in 20062007 it was realized that a much more comprehensive and focused effort to provide hydrologic climate change scenarios was needed if stakeholders and water professionals in the region were to take the next steps in preparing for climate change. Implications of global climate change for snowmelt hydrology in the 21st century, Modeling snow accumulation and ablation processes in forested environments, Uncertainties in hydrologic and climate change impact analyses in headwater basins of British Columbia. Additional details on the approach and methods are available in the CBCCSP study report (Hamlet, Carrasco, et al., Citation2010a). These parameters were chosen because they strongly affect the timing and volume of runoff production in the model simulations and are, in general, not available from observed data. Changes in snowpack are a key driver of hydrologic impacts in the PNW (Elsner et al., Citation2010; Hamlet & Lettenmaier, Citation1999b). Post-processing of the primary VIC model output (see Table 2) was carried out to produce a number of specific products discussed in the following sections. Thus, stakeholders can select different products, using different downscaling approaches that are appropriate to their needs. Lows in the upper 30s to lower 40s. Final calibration results for the model are shown in Fig. Thanks to Sean Fleming (Environment Canada) for spearheading this contribution to Atmosphere-Ocean. Why is a 1C increase such a big deal? For the CD and HD downscaling methods, which construct a 91-year time series for both historical and future time periods, three future time periods were selected: 2020s (20102039), 2040s (20302059), and 2080s (20702099). 95 0 obj
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The interested reader is directed to the CBCCSP report (Hamlet, Carrasco, et al., Citation2010a, Chapter 6) for a detailed discussion of methods and results. For example, researchers who wish to run their own hydrologic models can do so by downloading the statistically downscaled meteorological forcings from the study. 9. However, some areas west of the Cascade Range and in the northern Rockies show increasing AET. This approach was partly based on practical limitations on time and computational resources but was also informed by previous experience using the VIC model at finer spatial scales. The first nine months of the dataset were used for hydrologic model spin-up, resulting in 91 water years (OctoberSeptember) of usable historical data from the hydrologic model simulations. For each streamflow location (and its associated contributing basin area), a set of identical products is available on the study web site (CIG, Citation2013b). 8) experience little change in the shape of the monthly hydrograph because there is only occasional low-elevation snow in mid-winter in the twentieth century base case; therefore, there is relatively little sensitivity of monthly runoff timing to warming. Primary support for the project was provided by WDOE, with additional major support provided by the BPA, NWPCC, BCME, OWRD, and CTED via the 2009 WACCIA (http://cses.washington.edu/cig/res/ia/waccia.shtml) (Miles et al., Citation2010). These hydrologic studies support detailed assessment of the economic impacts of climate change on irrigation and important crops in WA (Yorgey et al., Citation2011), which in turn will inform decisions regarding best use of funding to improve water supply benefits in WA under climate change. The CBCCSP provided climate change projections of meteorological drivers and a calibrated VIC implementation in support of the study. (For example, Dworshak and Milner are nested within the larger Ice Harbor sub-basin.). This daily disaggregation technique sometimes introduces an undesirable discontinuity in the bias-corrected daily values at the beginning and end of months. Additional meteorological forcings needed for hydrologic model simulations (e.g., net incoming long- and shortwave radiation, dew point temperature, etc.) The study also used the ColSim reservoir operations model (Hamlet & Lettenmaier, Citation1999b) to estimate water deliveries to the Columbia Basin Project (the primary irrigation project supplied by water from Grand Coulee Dam) under future climate scenarios using streamflows generated by the integrated VIC/CropSyst model. 5 Examples of summary plots for monthly snow water equivalent (SWE) (mm) (averaged over the upstream basin area) and raw streamflow not adjusted for bias (cubic metres per second) for the Skagit River at Mount Vernon. Pink bands show the range of nine or ten HD climate change scenarios for B1 and A1B emissions scenarios for three future time periods. Fig. Act relating to state agency climate leadership, S. 5560, 61st Legislature (WA 2009). To support ecosystem research and impacts assessment, CIG extended the project to include specific meteorological and hydrological variables needed to support ecological studies (see discussion in Section 3). 2), for which overall errors in meteorological driving data were assumed to be relatively small; then, using these model parameters, to check the results in smaller sub-catchments. The top two panels show the Nash Sutcliffe Efficiency (NSE) (left) and R 2 (right) for the calibration period, while the two lower panels show NSE (left) and R 2 (right) for the validation period.