Modeled annual average daily maximum temperature, average for 2030-2059, using an ensemble mean of ten different global climate models and emissions senario A1B

Raster Dataset - GRID

Description Spatial Attributes

Keywords
Theme: climate change
Place: USFS Region 1

Description
Abstract
We use methods similar to those described in Mote and Salathé (2010) and Hamlet et al. (2010) to develop projections of future climate, fidelity of global climate models (GCMs) to regional climate, and use subsets of the GCMs to project future climate for several major river basins in the western United States (Columbia, upper Missouri, upper Colorado, and Great Basins). The basis of this downscaling are the GCMs also used for the Intergovernmental Panel on Climate Change (IPCC)'s fourth assessment (AR4) (e.g., Meehl et al. 2007a,b). The datasets used to generate the core datasets in this report can be obtained from the Coupled Model Intercomparison Project (CMIP3) website and are archived online by the Program for Climate Model Diagnosis and Intercomparison (PCMDI).



First, we analyzed GCMs available from the IPCC AR4 assessment to better understand the projected future regional climate, individual model sensitivities and regional differences in models used for downscaling. We then developed an ensemble of climate models that have the best capability in the basins in this project and use them to project sub-regional future climate based on an ensemble delta method. We also developed historical (1916-2006) and future (2030-2059, "2040s"; 2070-2099, "2080s") 1/16th degree (~6km) hydrologic output from the historical and future climate to estimate variables more useful for impacts assessment (e.g., snow water equivalent, soil moisture, potential evapotranspiration, runoff). The result is a consistent set of downscaled climate and hydrologic projections at 6km for the entire Columbia, upper Missouri, and upper Colorado basins and 12km for the Great and lower Colorado basins. The data are summarized at monthly time scales for Bailey's Ecosections, Omernik Level III Ecoregions, and 8-digit Hydrologic Unit Code (HUC 4) basins but are available in raw form on a grid-cell basis at daily time steps and in ascii grid (ArcGIS) format for observed and future climatologies of selected variables. For the ratio of April 1 SWE to cool season snowpack, a variable useful for categorizing watershed snowpack vulnerability to climate change, we have summarized data at 10 digit HUC basins.

Purpose
The goal of this project was to (1) develop consistent historical and future downscaled climate and hydrologic data and projections using the same methodology for several major river basins in the western United States (Columbia, upper Missouri, upper Colorado, and Great Basins) and (2) summarize that information in forms consistent with the needs of the funding agencies. This report describes where to get the information developed as well as the methods, results obtained, uses of and uncertainties associated with the data and projections.

Supplementary Information
This project was funded by a consortium of federal agencies that required new regional and summary data on climate change for planning purposes and impacts studies. Funding was provided by the United States Forest Service (USFS) Region 1, United States Fish and Wildlife Services (USFWS), USFS Rocky Mountain Research Station Boise Aquatic Sciences Lab, and USFS Region 6. The project builds on the considerable research effort and funding already devoted to similar goals in the Climate Impacts Group's Washington Climate Change Impacts Assessment (WACCIA, http://cses.washington.edu/cig/res/ia/waccia.shtml) and The Columbia Basin Climate Change Scenarios Project (2860, http://www.hydro.washington.edu/2860/), and would not have been possible without the resources and personnel associated with those projects.

_________________

Status of the data

Time period for which the data is relevant

Publication Information
_________________

Data storage and access information

Details about this document