Timing and Statistics of Autumn and Spring Annual Snow Cover for the Northern Hemisphere, 1972 to 2000, Version 1

This data set comprises a time series of annual snow cover data for the Northern Hemisphere (covering land primarily above 45 degrees North) from 1972 to 2000. Data are presented for land areas that exhibited snow cover in each of the 29 years. Variables are the week of snow disappearance, the week of snow cover onset, and the duration of the snow-free period. In addition, summary statistics for each parameter are provided. These are grids of the mean and the standard deviation for the three parameters.

本数据集包含1972年至2000年北半球（主要覆盖北纬45度以北陆地）的年度积雪覆盖时间序列数据。数据对应29年间每一年均存在积雪覆盖的陆地区域，所涉变量包括积雪消融周、积雪起始周以及无积雪期时长。此外，数据集还提供了各参数的汇总统计量，即上述三个参数的均值与标准差栅格数据。