F5EEC0ED-E4AA-444F-A272-8D235C99766C 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 1742 89.959935 row 298 89.959935 area true false 515992.227787 8409688.391568 515992.227787 8436496.452332 672702.435340 8436496.452332 672702.435340 8409688.391568 594347.331564 8423092.421950 center 32702 EPSG 9.8.8(3.0.1) EnviroAtlas - PRISM 30-Year Normal Annual Precipitation and Minimum and Maximum Temperature for American Samoa (1971–2000) 2007-01-01 creation 2025-11-04 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://https://prism.oregonstate.edu/normals_other/public/pacisl/grids/) and has a spatial resolution of 3 arcsec (80 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. For this project, Tutuila and Manua island domains were merged into one spatial domain for American Samoa using the "Mosaic to New Raster" tool in ArcGIS Pro. This dataset was processed 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/pacisl/metadata/): Abstract: This data set contains spatially gridded average monthly and annual precipitation and temperature for the climatological period 1971–2000. Distribution of the point measurements to a spatial grid was accomplished using the PRISM model, developed by Chris Daly of the PRISM Group, OSU. Purpose: Display and/or analyses requiring spatially distributed monthly or annual precipitation and temperature for the climatological period 1971–2000 Supplementary Information: There are many methods of interpolating climate 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 for a 30 yr climatological average (e.g. 1971- 2000 average) and an underlying grid such as a digital elevation model (DEM) to generate gridded estimates of monthly and 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 of temperature were produced by averaging the monthly grids, and summing for precipitation. Reports and papers on PRISM can be obtained from the PRISM Group website Completeness Report: Point estimates of precipitation and temperature originated from some or all of the following sources: 1) National Weather Service (NWS) Cooperative (COOP) stations, 2) Natural Resources Conservation Service (NRCS) SNOTEL, 3) United States Forest Service (USFS) and Bureau of Land Management (BLM) RAWS Stations, 4) Bureau of Reclemation (AGRIMET) stations, 5) California Data Exchange Center (CDEC) stations, 6) Storage guages, 7) NRCS Snowcourse stations, 8) Other State and local station networks, 9) Estimated station data, 10) Canadian stations, 11) Upper air stations, and 12) NWS/Federal Aviation Administration (FAA) Automated surface observation stations (ASOS). All COOP station data were subjected to quality control checks by the National Climatic Data Center (NCDC). All COOP, SNOTEL and other data were subjected to further quality control checks by the PRISM Group. These EnviroAtlas maps show 30-year normal annual precipitation and minimum and maximum temperature during 1971–2000 for American Samoa. 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/pacisl.php; PRISM Group, Oregon State University and Pacific Island Network, Inventory and Monitoring Program, National Park Service; https://prism.oregonstate.edu/normals_other/pacisl.php, data created January 2007, accessed 4 Nov 2025.). 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 and Pacific Island Network, Inventory and Monitoring Program, National Park Service; https://prism.oregonstate.edu/normals_other/pacisl.php, data created January 2007, accessed 5 Aug 2025. 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 American Samoa 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 -170.851819 -169.398286 -14.385004 -14.13733 1971-01-01T00:00:00 2000-12-31T00:00:00 PRISM_30_year_normals_maximum_temperature_degF_AMSAM_1971_2000.tif: maximum temperature (degrees Fahrenheit) – Annual 30-year "normal" dataset covering American Samoa averaged over the climatological period 1971–2000. physicalMeasurement 1 1 Band_1 87.89 74.46 Unified Code of Units of Measure [degF] 32 false false false false false PRISM_30_year_normals_minimum_temperature_degF_AMSAM_1971_2000.tif: minimum temperature (degrees Fahrenheit) – Annual 30-year "normal" dataset covering American Samoa averaged over the climatological period 1971–2000. physicalMeasurement 1 1 Band_1 76.69 66.45 Unified Code of Units of Measure [degF] 32 false false false false false PRISM_30_year_normals_precipitation_inches_AMSAM_1971_2000.tif: total precipitation (inches) – Annual 30-year "normal" dataset covering American Samoa averaged over the climatological period 1971–2000. physicalMeasurement 1 1 Band_1 295.62 88.2 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_AMSAM_1971_2000.zip download download https://enviroatlas.epa.gov/download/PRISM_30yr_normals_maximum_temperature_degF_AMSAM_1971_2000.zip download download https://enviroatlas.epa.gov/download/PRISM_30yr_normals_minimum_temperature_degF_AMSAM_1971_2000.zip download download https://enviroatlas.epa.gov/arcgis/rest/services/PRISM/PRISM_30yr_normals_precipitation_inches_AMSAM_1971_2000/ImageServer ESRI:ArcGIS offlineAccess https://enviroatlas.epa.gov/arcgis/rest/services/PRISM/PRISM_30yr_normals_maximum_temperature_degF_AMSAM_1971_2000/ImageServer ESRI:ArcGIS offlineAccess https://enviroatlas.epa.gov/arcgis/rest/services/PRISM/PRISM_30yr_normals_minimum_temperature_degF_AMSAM_1971_2000/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/pacisl/grids/ Data download needed for addition to EnviroAtlas. 2025-11-04T00:00:00 Rasters for the islands of Manua and Tutuila data were mosaicked together using the "mosaic" function from the "terra" package in R. Creating a more cohesive representation of the region for data visualization. 2025-11-04T00:00:00 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. 2025-11-04T00:00:00 Rasters were reprojected to the Universal Transverse Mercator (UTM) Zone 2 South projection using R programming software and the "terra" package. The CRS used for this projection is as follows: crs('+proj=utm +zone=2 +south +ellps=WGS84 +datum=WGS84'). We chose to project the PRISM rasters to a CRS that matches other EnviroAtlas layers in the American Samoa region. 2025-11-04T00:00:00 asNeeded 2025-08-07