Absolute Change in Snow Residence Time (CONUS) (Image Service)

The Snow Residence Time; Absolute Changes contains modeled absolute changes in snow residence time (SRT) calculated using a spatial analog model. The model ingests mean winter average temperature and precipitation. For more information about the model, please see Luce et al., [2014] and Lute and Luce [2017]. Absolute changes in snow residence time are in units of days. The temperature and precipitation data are ensemble mean values across 20 global climate models from the CMIP5 experiment [Taylor et al., 2012], downscaled to a 4km grid. For more information on the downscaling method and to access the raw data used to create this dataset, please see Abatzoglou and Brown, [2012] and the Northwest Climate Science Center. We used the MACAv2-metdata monthly precipitation and minimum and maximum temperature datasets for the period 1975-2005 (historical) and 2071-2090 (RCP8.5, future). Average temperature was calculated as the arithmetic mean of minimum and maximum temperature datasets. Average temperature was averaged over the winter months (November through March) and precipitation was summed over the winter months. More information on the project associated with this dataset is available from the U.S. Forest Service Rocky Mountain Research Station.

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.

积雪停留时间绝对变化量数据集包含通过空间类比模型计算得到的积雪停留时间（Snow Residence Time, SRT）绝对变化量。该模型以冬季平均气温与降水量作为输入参数。有关该模型的详细信息，请参阅Luce等[2014]以及Lute与Luce[2017]的研究文献。积雪停留时间绝对变化量的单位为天。
气温与降水数据取自耦合模式比较计划第五阶段（Coupled Model Intercomparison Project Phase 5, CMIP5）试验中20个全球气候模式的集合平均结果，并经降尺度处理至4km分辨率格网。如需了解降尺度方法的详细说明，或获取本数据集的原始数据，请参阅Abatzoglou与Brown[2012]的研究成果，以及西北气候科学中心的相关内容。
本数据集采用了1975-2005年（历史时段）与2071-2090年（典型浓度路径8.5，即Representative Concentration Pathway 8.5, RCP8.5未来情景）的MACAv2月尺度降水、最低与最高气温数据集。平均气温由最低气温与最高气温数据集的算术平均值计算得到。平均气温取冬季（11月至次年3月）的均值，降水量则统计冬季时段的总量。有关本数据集所属项目的更多信息，可通过美国林务局落基山研究站获取。

本数据集记录取自美国农业部（United States Department of Agriculture, USDA）企业数据清单，该清单汇入https://data.gov目录。本数据集记录包含以下资源：ISO-19139元数据、ArcGIS Hub数据集、ArcGIS地理服务。如需获取完整信息，请访问https://data.gov。