4AA48BB0-5A3A-4E45-A246-0F33D6330566 eng utf8 dataset dataset EnviroAtlas Coordinator U.S. Environmental Protection Agency, Office of Research and Development - Center for Public Health and Environmental Assessment (CPHEA), EnviroAtlas Geospatial Data Owner (919) 541-3832 109 T.W. Alexander Drive Research Triangle Park NC 27709 EnviroAtlas@epa.gov https://www.epa.gov/enviroatlas pointOfContact 2025-12-04 ISO 19139 Geographic Information - Metadata - Implementation Specification 2007 2 column 9225 481.577338 row 5611 481.577338 area true false -2305058.170894 54463.343446 -2305058.170894 2756593.788979 2137492.775469 2756593.788979 2137492.775469 54463.343446 -83782.697713 1405528.566212 center 3338 EPSG 6.12(9.3.0.0) EnviroAtlas - PRISM 30-Year Normal Annual Precipitation and Minimum and Maximum Temperature for Alaska (1981–2010) 2018-10-08 creation 2025-09-29 publication U.S. Environmental Protection Agency (US EPA) originator U.S. EPA Office of Research and Development (ORD) - Center for Public Health and Environmental Assessment (CPHEA) Research Triangle Park, NC publisher mapDigital This annual data was accessed from the PRISM project website (https://prism.oregonstate.edu/normals_other/public/alaska/grids/) and has a spatial resolution of 30 arcsec (800 m). The three climatic variables included in the dataset are total precipitation (inches), maximum temperature (degrees Fahrenheit), and minimum temperature (degrees Fahrenheit). PRISM Climate Group at Oregon State University used climate observations from monitoring stations and interpolated to a gridded format using the PRISM model (Parameter-elevation Regressions on Independent Slopes Model). Interpolation was trained using a DEM (digital elevation model) to improve performance in mountainous regions. The PRISM temperature data were originally reported in °C but were converted to °F. The PRISM precipitation data were originally reported in millimeters but were converted to inches. This dataset was produced by the US EPA to support research and online mapping activities related to EnviroAtlas. EnviroAtlas (https://www.epa.gov/enviroatlas) allows the user to interact with a web-based, easy-to-use, mapping application to view and analyze multiple ecosystem services for the contiguous United States. The dataset is available as downloadable data (https://edg.epa.gov/data/Public/ORD/EnviroAtlas) or as an EnviroAtlas map service. Additional descriptive information about each attribute in this dataset can be found in its associated EnviroAtlas Fact Sheet (https://www.epa.gov/enviroatlas/enviroatlas-fact-sheets). From Original PRISM Metadata (https://prism.oregonstate.edu/normals_other/public/alaska/metadata/): Abstract: Monthly 30-year "normal" dataset covering Alaska, averaged over the climatological period 1981–2010. Contains spatially gridded average annual precipitation and maximum temperature at 800m grid cell resolution. Distribution of the point measurements to the spatial grid was accomplished using the PRISM model, developed and applied by Dr. Christopher Daly of the PRISM Climate Group at Oregon State University. This dataset was heavily peer reviewed, and is available free-of-charge on the PRISM website. Purpose: Display and/or analysis requiring spatially distributed annual precipitation and temperature for the climatological period 1981–2010. Supplementary Information: There are many methods of interpolating climate data from monitoring stations to grid points. Some provide estimates of acceptable accuracy in flat terrain, but few have been able to adequately explain the extreme, complex variations in climate that occur in mountainous regions. Significant progress in this area has been achieved through the development of PRISM (Parameter-elevation Regressions on Independent Slopes Model). PRISM is an analytical model that uses point data and an underlying grid such as a digital elevation model (DEM) to generate gridded estimates of monthly or annual precipitation and temperature (as well as other climatic parameters). PRISM is well suited to regions with mountainous terrain, because it incorporates a conceptual framework that addresses the spatial scale and pattern of orographic processes. Grids were modeled on a monthly basis. Annual grids were produced by averaging (temperatures) or summing (precipitation) the monthly grids. Climatological data were collected for several research and government networks through a data delivery from the Arctic Landscape Conservation Cooperative's Imiq Hydroclimate Database including: the University of Alaska Fairbanks' Water and Environmental Research Center (WERC) and International Arctic Research Center (IARC); Arctic Observation Network (AON); Circumarctic Lakes Observation Network (CALON); Arctic Long Term Ecological Research (LTER); Bureau of Ocean Energy Management (BOEM); RWIS (Roadway Weather Information System); Department of Interior’s Bureau of Land Management (BLM) and Geological Survey (USGS). Climate data were also collected and processed for the National Weather Service's (NWS) Cooperative Observer Program (COOP), Weather Bureau Army/Navy (WBAN), and surface hourly stations from the National Centers for Environmental Information (NCEI); Soil Climate Analysis Network (SCAN), Snow Telemetry (SNOTEL), and Snow Course stations from the Department of Agriculture's Natural Resources Conservation Service (NRCS); Remote Automatic Weather Stations (RAWS) from the Western Regional Climate Center (WRCC) and MesoWest; Community Collaborative Rain Hail and Snow network (CoCoRaHS); National Data Buoy Center (NDBC); and the Hydrometeorological Design Studies Center (HDSC). Additional surface hourly data and the NWS Daily Hydrometeorological Product were collected via the Unidata Internet Data Distribution project (IDD). Data from the Fairbanks and Juneau Weather Forecast Offices, Alaska Department of Transportation (AKDOT), and the Hydrometeorological Automated Data System (HADS) network were also obtained from MesoWest. Data for the Central Alaska Inventory and Monitoring Network (CAKN), Juneau Icefield Research Program (JIRP), McCall Glacier, and Chugach National Forest Avalanche Information Center (CNFAIC) were made available through, or with the assistance of, the National Park Service (NPS). Data for the Alaska-Canada border region were obtained from Environment Canada, the Pacific Climate Impacts Consortium (PCIC) and NCEI. These EnviroAtlas maps show 30-year normal annual precipitation and minimum and maximum temperature during 1981–2010 for Alaska. Temperature is displayed in degrees Fahrenheit (°F) and precipitation is displayed in inches (in). Data sets are based on the Parameter-elevation Regressions on Independent Slopes Model (PRISM) developed by the PRISM Climate Group at Oregon State University (https://prism.oregonstate.edu/normals_other/alaska.php; Daly, C., et al. 2018, 1981–2010 High-Resolution Temperature and Precipitation Maps for Alaska. Final Report. PRISM Climate Group, Oregon State University Corvallis, Oregon). The overall goal of EnviroAtlas is to employ and develop the best available science to map indicators of ecosystem services production, demand, and drivers for the nation. PRISM Group, Oregon State University, https://prism.oregonstate.edu/normals_other/alaska.php, data created Oct 2018, accessed 5 Aug 2025. Daly, C., et al. 2018, 1981–2010 High-Resolution Temperature and Precipitation Maps for Alaska. Final Report. PRISM Climate Group, Oregon State University Corvallis, Oregon. Daly, C., Halbleib, M., Smith, J.I., Gibson, W.P., Doggett, M.K., Taylor, G.H., Curtis, J., and Pasteris, P.A. 2008. Physiographically-sensitive mapping of temperature and precipitation across the conterminous United States. International Journal of Climatology, 28: 2031-2064. [2] Daly, C., J.I. Smith, and K.V. Olson. 2015. Mapping atmospheric moisture climatologies across the conterminous United States. PloS ONE 10(10):e0141140. doi:10.1371/journal.pone.0141140. completed EnviroAtlas Coordinator U.S. Environmental Protection Agency, Office of Research and Development - Center for Public Health and Environmental Assessment (CPHEA), EnviroAtlas Geospatial Data Owner (919) 541-3832 109 T.W. Alexander Drive Research Triangle Park NC 27709 EnviroAtlas@epa.gov https://www.epa.gov/enviroatlas publisher asNeeded Alaska United States place EPA Place Names 2015-01-31 publication Climate Ecosystem Environment Hazards Human Impact Modeling Risk Water theme EPA GIS Keyword Thesaurus 2007-11-02 publication 020:072 theme Federal Program Inventory 2013-09-16 publication Ecosystem Services EnviroAtlas Environment Environmental Atlas Human Well-being Sustainability theme User 2022-01-11 publication None. Please check sources, scale, accuracy, currency and other available information. Please confirm that you are using the most recent copy of both data and metadata. Acknowledgement of the EPA would be appreciated. EPA Public Domain License licenseUnrestricted https://edg.epa.gov/EPA_Data_License.html unclassified https://project-open-data.github.io/schema/#accessLevel grid eng utf8 Microsoft Windows 10 Version 10.0 (Build 22631) ; Esri ArcGIS 13.5.0.57366 true -180 180 45.663945 74.936568 1981-01-01T00:00:00 2010-01-01T00:00:00 PRISM_30_year_normals_maximum_temperature_degF_AK_1981_2010.tif: maximum temperature (degrees Fahrenheit) – Annual 30-year "normal" dataset covering Alaska averaged over the climatological period 1981–2010. physicalMeasurement 1 1 Band_1 53.02 -18.84 Unified Code of Units of Measure [degF] 32 false false false false false PRISM_30_year_normals_minimum_temperature_degF_AK_1981_2010.tif: minimum temperature (degrees Fahrenheit) – Annual 30-year "normal" dataset covering Alaska averaged over the climatological period 1981–2010. physicalMeasurement 1 1 Band_1 43.49 -30.23 Unified Code of Units of Measure [degF] 32 false false false false false PRISM_30_year_normals_precipitation_inches_AK_1981_2010.tif: total precipitation (inches) – Annual 30-year "normal" dataset covering Alaska averaged over the climatological period 1981–2010. physicalMeasurement 1 1 Band_1 411.73 4.09 Unified Code of Units of Measure [in_us] 32 false false false false false Raster Dataset https://enviroatlas.epa.gov/download/PRISM_30yr_normals_precipitation_inches_AK_1981_2010.zip download download https://enviroatlas.epa.gov/download/PRISM_30yr_normals_maximum_temperature_degF_AK_1981_2010.zip download download https://enviroatlas.epa.gov/download/PRISM_30yr_normals_minimum_temperature_degF_AK_1981_2010.zip download download https://enviroatlas.epa.gov/arcgis/rest/services/PRISM/PRISM_30yr_normals_precipitation_inches_AK_1981_2010/ImageServer ESRI:ArcGIS offlineAccess https://enviroatlas.epa.gov/arcgis/rest/services/PRISM/PRISM_30yr_normals_minimum_temperature_degF_AK_1981_2010/ImageServer ESRI:ArcGIS offlineAccess https://enviroatlas.epa.gov/arcgis/rest/services/PRISM/PRISM_30yr_normals_maximum_temperature_degF_AK_1981_2010/ImageServer ESRI:ArcGIS offlineAccess https://www.epa.gov/enviroatlas/enviroatlas-data information information https://www.epa.gov/enviroatlas information information dataset Tests for integrity have not been performed. EPA National Geospatial Data Policy Features have been reviewed by U.S. EPA EnviroAtlas Project Managers for public release. true Features represented have not been tested for completeness EPA National Geospatial Data Policy Features have been reviewed by U.S. EPA EnviroAtlas Project Managers for public release. true Processing Steps are listed below for the processing of the original PRISM datasets for addition to EnviroAtlas. Annual data were downloaded for all variables (precipitation, minimum temperature, and maximum temperature) from PRISM website: https://prism.oregonstate.edu/normals_other/public/alaska/grids/ Data download needed for addition to EnviroAtlas. 2025-08-05T00:00:00 Rasters were projected to the NAD 1983 projection documented in the PRISM metadata using R programming software and the "terra" package. The CRS used for this projection is as follows: crs('+proj=longlat +ellps=GRS80 +datum=NAD83 +units=m +no_defs +type=crs'). Raw rasters downloaded from the PRISM website did not have spatial reference information and therefore this information needed to be appropriately assigned based on PRISM documentation. 2025-09-25T00:00:00 Minimum and maximum temperature files were converted from degrees Celsius to degrees Fahrenheit. Precipitation files were converted from millimeters to inches. Data needs to match the convention of imperial units of measurement on EnviroAtlas. 2025-09-25T00:00:00 Rasters were reprojected to a custom Albers Equal Area projection using R programming software and the "terra" package. The CRS used for this projection is as follows: crs('+proj=aea +lat_1=55.0 +lat_2=65.0 +lon_0=-154 +lat_0=50 +x_0=0 +y_0=0 +ellps=GRS80 +datum=NAD83'). We chose to project the PRISM rasters to a CRS that matches other EnviroAtlas layers for Alaska. 2025-09-25T00:00:00 asNeeded 2025-08-07