Absolute Change in April 1 Snow Water Equivalent (CONUS) (Image Service)

The April Snow Water Equivalent data were modeled using the spatial analog models of Luce et al. [https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/2013WR014844] (see also https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/2017WR020752). These models are built on precipitation and snow data from Snowpack Telemetry (SNOTEL) stations across the western United States and temperature data from 1975-2005. To simulate historical and future gridded snow, the models ingest gridded winter cumulative precipitation and winter average temperature (from the MACAv2-Metdata dataset). We used the MACAv2-metdata monthly precipitation and minimum and maximum temperature datasets for the period 2071-2090 (RCP8.5). 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.本四月雪水当量（Snow Water Equivalent, SWE）数据集采用Luce等人提出的空间类比模型进行建模[https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/2013WR014844]（另可参考文献[https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/2017WR020752]）。该类模型基于美国西部全域雪包遥测（Snowpack Telemetry, SNOTEL）站点的降水与积雪数据，以及1975-2005年的气温数据构建。为模拟历史与未来网格化积雪，该模型以来自MACAv2-Metdata数据集的网格化冬季累积降水量与冬季平均气温作为输入数据。本研究采用2071-2090年时段的MACAv2-Metdata逐月降水、最低与最高气温数据集（典型浓度路径RCP8.5, Representative Concentration Pathway 8.5），其中平均气温由月度最低与最高气温数据集的算术平均值计算得到；冬季时段定义为11月至次年3月，冬季平均气温取该时段内各月平均气温的均值，冬季降水量则对该时段内各月的降水量进行累加求和。关于本数据集关联项目的更多信息，可从美国林务局落基山研究站获取。