Percent change in winter precipitation (CONUS) (Image Service)

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.\n\nHistorical (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; 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.\n\nRaster 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).This record was taken from the USDA Enterprise Data Inventory that feeds into the https://data.gov catalog. Data for this record includes the following resources: ISO-19139 metadata ArcGIS Hub Dataset ArcGIS GeoService For complete information, please visit https://data.gov.

国家森林气候变化地图项目由落基山研究站（RMRS）和可持续性及气候变化办公室共同开发，旨在满足国家森林管理者对决策过程中相关气候变化的预测信息的需求，该信息以适合森林规划等决策过程的比例尺提供。这些地图采用了最前沿的科学方法，覆盖了美国所有连续森林区域的相关数据。目前，地图集包括与降水、空气温度、雪（包括积雪停留时间和4月1日的积雪水当量）以及河流流量相关的变量。

美国连续区域的1975-2005年历史和2071-2090年未来降水和温度数据是CMIP5实验（https://journals.ametsoc.org/doi/abs/10.1175/BAMS-D-11-00094.1）中20个全球气候模型的集合平均值，并下采样到4公里网格。关于下采样方法以及获取数据的详细信息，请参阅Abatzoglou和Brown（2012年）（https://rmets.onlinelibrary.wiley.com/doi/full/10.1002/joc.2312）以及西北知识网络（https://climate.northwestknowledge.net/MACA/）。我们使用了MACAv2- Metadata月度数据集；将相关季节（年度、冬季或夏季）的月降水量（毫米）相加。然后计算历史时期和未来时期之间的绝对变化和百分比变化。

栅格数据也可从RMRS网站（https://www.fs.usda.gov/rm/boise/AWAE/projects/NFS-regional-climate-change-maps/categories/us-raster-layers.html）下载，以及pdf地图和详细的元数据（https://www.fs.usda.gov/rm/boise/AWAE/projects/NFS-regional-climate-change-maps/downloads/NationalForestClimateChangeMapsMetadata.pdf）。本记录来自向https://data.gov目录提供数据的美国农业部企业数据目录。本记录的数据包括以下资源：ISO-19139元数据、ArcGIS Hub数据集、ArcGIS GeoService。如需完整信息，请访问https://data.gov。