Typical annual rainfall data were summarized from monthly precipitation data and provided in millimeters (mm). The monthly climate data for global land areas were generated from a large network of weather stations by the WorldClim project. Precipitation and temperature data were collected from the weather stations and aggregated across a target temporal range of 1970-2000.

Weather station data (between 9,000 and 60,000 stations) were interpolated using thin-plate splines with covariates including elevation, distance to the coast, and MODIS-derived minimum and maximum land surface temperature. Spatial interpolation was first done in 23 regions of varying size depending on station density, instead of the common approach to use a single model for the entire world. The satellite imagery data were most useful in areas with low station density. The interpolation technique allowed WorldClim to produce high spatial resolution (approximately 1 km2) raster data sets.

The National Forest Climate Change Maps project was developed by the Rocky Mountain Research Station (RMRS) and the Office of Sustainability and Climate to meet the needs of national forest managers for information on projected climate changes at a scale relevant to decision making processes, including forest plans. The maps use state-of-the-art science and are available for every national forest in the contiguous United States with relevant data coverage. Currently, the map sets include variables related to precipitation, air temperature, snow (including snow residence time and April 1 snow water equivalent), and stream flow.Historical (1975-2005) and future (2071-2090) precipitation and temperature data for the contiguous United States are ensemble mean values across 20 global climate models from the CMIP5 experiment (https://res1journalsd-o-tametsocd-o-torg.vcapture.xyz/doi/abs/10.1175/BAMS-D-11-00094.1), downscaled to a 4 km grid. For more information on the downscaling method and to access the data, please see Abatzoglou and Brown, 2012 (https://res1rmetsd-o-tonlinelibraryd-o-twileyd-o-tcom.vcapture.xyz/doi/full/10.1002/joc.2312) and the Northwest Knowledge Network (https://res1climated-o-tnorthwestknowledged-o-tnet.vcapture.xyz/MACA/). We used the MACAv2- Metdata monthly dataset; monthly precipitation values (mm) were summed over the season of interest (annual, winter, or summer). Absolute and percent change were then calculated between the historical and future time periods.Raster data are also available for download from RMRS site (https://res1wwwd-o-tfsd-o-tusdad-o-tgov.vcapture.xyz/rm/boise/AWAE/projects/NFS-regional-climate-change-maps/categories/us-raster-layers.html), along with pdf maps and detailed metadata (https://res1wwwd-o-tfsd-o-tusdad-o-tgov.vcapture.xyz/rm/boise/AWAE/projects/NFS-regional-climate-change-maps/downloads/NationalForestClimateChangeMapsMetadata.pdf).

The National Forest Climate Change Maps project was developed by the Rocky Mountain Research Station (RMRS) and the Office of Sustainability and Climate to meet the needs of national forest managers for information on projected climate changes at a scale relevant to decision making processes, including forest plans. The maps use state-of-the-art science and are available for every national forest in the contiguous United States with relevant data coverage. Currently, the map sets include variables related to precipitation, air temperature, snow (including snow residence time and April 1 snow water equivalent), and stream flow.

Historical (1975-2005) and future (2071-2090) precipitation and temperature data for the state of Alaska were developed by the Scenarios Network for Alaska and Arctic Planning (SNAP) (https://snap.uaf.edu). Monthly precipitation values (mm) were summed over the season of interest (annual, winter, or summer). These datasets have several important differences from the MACAv2-Metdata (https://climate.northwestknowledge.net/MACA/) products, used in the contiguous U.S. They were developed using different global circulation models and different downscaling methods, and were downscaled to a different scale (771 m instead of 4 km). While these cover the same time periods and use broadly similar approaches, caution should be used when directly comparing values between Alaska and the contiguous United States.

Raster data are also available for download from RMRS site (https://www.fs.fed.us/rm/boise/AWAE/projects/NFS-regional-climate-change-maps/categories/us-raster-layers.html), along with pdf maps and detailed metadata (https://www.fs.fed.us/rm/boise/AWAE/projects/NFS-regional-climate-change-maps/downloads/NationalForestClimateChangeMapsMetadata.pdf).

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Total annual precipitation is shown along with elevation hillshade using the NAGI method. Hillshade is from Esri Elevation Service, and precipitation data is taken from WMO and FAO rain gages in addition to a number of national datasets. The annual and monthly averages for the period 1950-2000 was calculated and interpolated by WorldClim.org, a collaboration between the University of California, Berkeley, the International Cetner for Tropical Agrilculture, and the Cooperative Research Centre for Tropical Rainforest Ecology and Management.

Information on precipitation includes mean annual precipitation (MAP) ± the standard deviation of annual precipitation and (in parentheses) the minimum annual precipitation recorded in 1971–2006. Because rainfall data from Kuke do not exist, the values reported are from Ghanzi.

Contained within the 3rd Edition (1957) of the Atlas of Canada is a plate that shows two maps for the annual total precipitation. Annual precipitation is defined as the sum of rainfall and the assumed water equivalent of snowfall for a given year. A specific gravity of 0.1 for freshly fallen snow is used, which means that ten inches (25.4 cm) of freshly fallen snow is assumed to be equal to one inch (2.54 cm) of rain. The mean annual total precipitation and snowfall maps on this plate are primarily based on thirty-year data during the period 1921 to 1950 inclusive.

1km gridded Rainfall map - interpolation over DEM. Rainfall data scattered well except Western and Southern Highlands Provinces. With the Digicel Towers (mounted with rainfall instruments) network nation-wide. The Rainfall Map can be improved.

Date of freeze for historical (1985-2005) and future (2071-2090, RCP 8.5) time periods, and absolute change between them, based on analysis of MACAv2METDATA. Download this data or get more information

This dataset contains annual average precipitation from the four models and two greenhouse gas (RCP) scenarios included in the four model ensemble for the years 1950-2099. The downscaling and selection of models for inclusion in ten and four model ensembles is described in Pierce et al. 2018, but summarized here. Thirty two global climate models (GCMs) were identified to meet the modeling requirements. From those, ten that closely simulate California’s climate were selected for additional analysis (Table 1, Pierce et al. 2018) and to form a ten model ensemble. From the ten model ensemble, four models, forming a four model ensemble, were identified to provide coverage of the range of potential climate outcomes in California. The models in the four model ensemble and their general climate projection for California are: HadGEM2-ES (warm/dry),CanESM2 (average), CNRM-CM5 (cooler/wetter),and MIROC5 the model least like the others to improve coverage of the range of outcomes. These data were downloaded from Cal-Adapt and prepared for use within CA Nature by California Natural Resource Agency and ESRI staff. Cal-Adapt. (2018). LOCA Derived Data [GeoTIFF]. Data derived from LOCA Downscaled CMIP5 Climate Projections. Cal-Adapt website developed by University of California at Berkeley’s Geospatial Innovation Facility under contract with the California Energy Commission. Retrieved from https://cal-adapt.org/ Pierce, D. W., J. F. Kalansky, and D. R. Cayan, (Scripps Institution of Oceanography). 2018. Climate, Drought, and Sea Level Rise Scenarios for the Fourth California Climate Assessment. California’s Fourth Climate Change Assessment, California Energy Commission. Publication Number: CNRA-CEC-2018-006.

Precipitation is derived from water vapour in the air, and it includes all forms of moisture falling on the earth's surface. Condensed water vapour accumulates in clouds, and precipitation occurs when the constituent ice crystals or water droplets grow too large to resist gravitational attraction to earth. The atmospheric moisture lost through precipitation is replenished by transpiration from vegetation, and by evaporation from the soil and from water bodies. The oceans, which cover 71 per cent of the earth's surface, are the primary source, though large fresh water bodies may be important locally, particularly in more southern latitudes. The map shows the annual precipitation (in millimetres) based on the 30-year period 1941 – 1970. The map was prepared from measurements at stations in the national precipitation network. In 1974 this network consisted of about 2700 stations, however, many have been in existence for only short periods. For statistical analysis a long series of data is required. To begin the map, those stations having a complete 25-year record for the standard normal period 1941-1970 were selected. The average yearly precipitation value for each station was plotted on a 1:5,000,000-scale relief map. The density of stations was too coarse for isoline interpolation, particularly in arctic and mountainous regions. For additional detail, all stations with a continuous record of 10-24 years were then sorted from the archive file and scrutinized. It was possible in many cases to adjust the mean values to the 30-year normal period by assuming a constant difference between the short-period station and a nearby long-term reference station. The computed correction indices occasionally gave erroneous values however, even following elevation slope adjustments. It was assumed that these inconsistencies resulted from the reference station being too far distant or from dissimilarity in site characteristics. In the end, three sets of points were plotted, using colour codes to denote confidence. A station with a full record was considered accurate for that point; though isoline interpolation would take into account the surrounding terrain. A station with a shorter record, but which had been successfully adjusted, was considered almost as good as the long term station. Stations that could not be adjusted were treated as guidance points only. In remote areas greater reliance had to be allocated to these stations, but this was compensated by a more conservative approach to isoline selection. For reasons of scale the isoline interval is greater in the Western Cordillera than for the rest of Canada. Final modifications to the map were based on a review of previously constructed maps, and a survey of special precipitation measurements and research undertaken in mountainous and other imperfectly known regions.

Projected changes in annual precipitation in percentages under A1B scenario, multi-model ensemble mean for the time periods 2021-2050 relative to 1961-1990 mean. Map presents changes using ensemble mean of several regional climate models (RCMs), run by different climate modelling communities in the frame of the EU FP6 Integrated Project ENSEMBLES (Contract number 505539). Data are presented as changes in relative terms (according to 1961-1990 period) in spatial resolution of approximately 25 km.

Analysis of ‘Weather Stations Used to Compile the Mean Annual Precipitation Map for Idaho’ provided by Analyst-2 (analyst-2.ai), based on source dataset retrieved from https://catalog.data.gov/dataset/1ba4ff80-aa37-40c6-84c8-e65da2913256 on 12 November 2021.

--- Dataset description provided by original source is as follows ---

--- Original source retains full ownership of the source dataset ---

This EnviroAtlas dataset provides the average annual precipitation by 12-digit Hydrologic Unit (HUC). The values were estimated from maps produced by the PRISM Climate Group, Oregon State University. The original data was at the scale of 800 m grid cells representing average precipitation from 1981-2010 in mm. The data was converted to inches of precipitation and then zonal statistics were estimated for a final value of average annual precipitation for each 12 digit HUC. For more information about the original dataset please refer to the PRISM website at http://www.prism.oregonstate.edu/. 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).

This dataset provides lines of equal average annual precipitation for water years 1961-90 in the Black Hills area of South Dakota.

The National Forest Climate Change Maps project was developed by the Rocky Mountain Research Station (RMRS) and the Office of Sustainability and Climate to meet the needs of national forest managers for information on projected climate changes at a scale relevant to decision making processes, including forest plans. The maps use state-of-the-art science and are available for every national forest in the contiguous United States with relevant data coverage. Currently, the map sets include variables related to precipitation, air temperature, snow (including snow residence time and April 1 snow water equivalent), and stream flow.

Historical (1975-2005) and future (2071-2090) precipitation and temperature data for the contiguous United States are ensemble mean values across 20 global climate models from the CMIP5 experiment (https://journals.ametsoc.org/doi/abs/10.1175/BAMS-D-11-00094.1), downscaled to a 4 km grid. For more information on the downscaling method and to access the data, please see Abatzoglou and Brown, 2012 (https://rmets.onlinelibrary.wiley.com/doi/full/10.1002/joc.2312) and the Northwest Knowledge Network (https://climate.northwestknowledge.net/MACA/). We used the MACAv2- Metdata monthly dataset; average temperature values were calculated as the mean of monthly minimum and maximum air temperature values (degrees C), averaged over the season of interest (annual, winter, or summer). Absolute and percent change were then calculated between the historical and future time periods.

Historical (1975-2005) and future (2071-2090) precipitation and temperature data for the state of Alaska were developed by the Scenarios Network for Alaska and Arctic Planning (SNAP) (https://snap.uaf.edu). These datasets have several important differences from the MACAv2-Metdata (https://climate.northwestknowledge.net/MACA/) products, used in the contiguous U.S. They were developed using different global circulation models and different downscaling methods, and were downscaled to a different scale (771 m instead of 4 km). While these cover the same time periods and use broadly similar approaches, caution should be used when directly comparing values between Alaska and the contiguous United States.

Raster data are also available for download from RMRS site (https://www.fs.usda.gov/rm/boise/AWAE/projects/NFS-regional-climate-change-maps/categories/us-raster-layers.html), along with pdf maps and detailed metadata (https://www.fs.usda.gov/rm/boise/AWAE/projects/NFS-regional-climate-change-maps/downloads/NationalForestClimateChangeMapsMetadata.pdf).

These data represent mean annual precipitation (in inches) for Idaho for the climatological period 1961-90. Average annual precipitation is the average of the annual amount of precipitation for a location over a year. Data used to delineate these boundaries are from Idaho weather stations (1961-90).Source data for this web service can be downloaded from https://res1insideidahod-o-torg.vcapture.xyz/data/ago/ics/ppt_id_ics.zip.A printed map is available: https://res1alliance-primod-o-thostedd-o-texlibrisgroupd-o-tcom.vcapture.xyz/permalink/f/m1uotc/CP71168920310001451 from the University of Idaho Map Room. Additionally, a related research report is available: https://res1alliance-primod-o-thostedd-o-texlibrisgroupd-o-tcom.vcapture.xyz/permalink/f/m1uotc/CP71180601950001451.Related data set: Weather Stations Used to Compile the Mean Annual Precipitation Map for Idaho

Average historical annual total precipitation (mm) and projected relative change in total precipitation (% change from baseline) for Northern Alaska. 30-year averages. Handout format. Maps created using the SNAP 5-GCM composite (AR5-RCP 8.5) and CRU TS3.1.01 datasets.

The WMS Service (Web Map Service) called Annual Average Precipitation (1940/41-2005/06) allows the visualization and consultation of this cartography that contains, in each pixel, the annual average precipitation in the period 1940-2005 in natural regime used for the calculation of the contributions from the SIMPA model. The URL of the WMS Service is: https://wms.mapama.gob.es/sig/water/EvalRecHidricos/1940_2005/Precipitacion/wms.aspx The reference systems offered by this service are: - For geographical coordinates: CRS: 84, EPSG: 4230 (ED50), EPSG:4326 (WGS 84), EPSG:4258 (ETRS 89). - For U.T.M coordinates: EPSG:32628 (WGS 84 / UTM zone 28N), EPSG:32629 (WGS 84 / UTM zone 29N), EPSG:32630 (WGS 84 / UTM zone 30N), EPSG:32631 (WGS 84 / UTM zone 31N), EPSG:25828 (ETRS 89 / UTM zone 28N), EPSG:25829 (ETRS 89 / UTM zone 29N), EPSG:25830 (ETRS 89 / UTM zone 30N), EPSG:25831 (ETRS 89 / UTM zone 31N), EPSG:23028 (ED50 / UTM zone 28N), EPSG:23029 (ED50 / UTM zone 29N), EPSG:23030 (ED50 / UTM zone 30N), EPSG:23031 (ED50 / UTM zone 31N).

[Metadata] Mean Annual Rainfall Isohyets in Millimeters for the Islands of Hawai‘i, Kaho‘olawe, Kaua‘i, Lāna‘i, Maui, Moloka‘i and O‘ahu. Source: 2011 Rainfall Atlas of Hawaii, https://www.hawaii.edu/climate-data-portal/rainfall-atlas. Note that Moloka‘I data/maps were updated in 2014. Please see Rainfall Atlas final report appendix for full method details: https://www.hawaii.edu/climate-data-portal/rainfall-atlas. Statewide GIS program staff downloaded data from UH Geography Department, Rainfall Atlas of Hawaii, February, 2019. Annual and monthly isohyets of mean rainfall were available for download. The statewide GIS program makes available only the annual layer. Both the monthly layers and the original annual layer are available from the Rainfall Atlas of Hawaii website, referenced above. Note: Contour attribute value represents the amount of annual rainfall, in millimeters, for that line/isohyet. For additional information, please see metadata at https://files.hawaii.gov/dbedt/op/gis/data/isohyets.pdf or contact Hawaii Statewide GIS Program, Office of Planning and Sustainable Development, State of Hawaii; PO Box 2359, Honolulu, Hi. 96804; (808) 587-2846; email: gis@hawaii.gov; Website: https://planning.hawaii.gov/gis.