Some of the YKL rasters intentionally do not align or have the same extent. These rasters were not snapped to a common raster per the authors' discretion. Please review selected rasters prior to use. These varying alignments are a result of the use of differing source data sets and all products derived from them. We recommend that users snap or align rasters as best suits their own projects. - This set of files includes downscaled projections of decadal averages of annual total precipitation (in millimeters, no unit conversion necessary) for each of the decades 2010-2019, 2020-2029, 2050-2059, and 2060-2069 at 771x771 meter spatial resolution. Each file represents a decadal mean of an annual total calculated from monthly totals. The spatial extent is clipped to the YKL REA boundary bounding box. Overview: This set of files is an average of five top performing Global Climate Models. These models are referred to by the acronyms: cccma_cgcm31, mpi_echam5, gfdl_cm21, ukmo_hadcm3, and miroc3_2_medres. For a description of the model selection process, please see Walsh et al. 2008. Global Climate Model Performance over Alaska and Greenland. Journal of Climate. v. 21 pp. 6156-6174 This set of files represents the A2 projected emission scenario. Emission scenarios in brief: The Intergovernmental Panel on Climate Change (IPCC) Special Report on Emissions Scenarios (SRES) created a range of scenarios to explore alternative development pathways, covering a wide range of demographic, economic and technological driving forces and resulting greenhouse gas emissions. The B1 scenario describes a convergent world, a global population that peaks in mid-century, with rapid changes in economic structures toward a service and information economy. The Scenario A1B assumes a world of very rapid economic growth, a global population that peaks in mid-century, rapid introduction of new and more efficient technologies, and a balance between fossil fuels and other energy sources. The A2 scenario describes a very heterogeneous world with high population growth, slow economic development and slow technological change. These files are bias corrected and downscaled via the delta method using PRISM (http://prism.oregonstate.edu/) 1971-2000 771m data as baseline climate. Absolute anomalies are utilized for temperature variables. Proportional anomalies are utilized for precipitation variables. Please see http://www.snap.uaf.edu/about for a description of the downscaling process.