A worldwide wolverine distribution model based on late-spring snow cover from 2000-2006

This data publication contains raster datasets (GeoTiff format) developed using MODIS (Moderate Resolution Imaging Spectroradiometer) classified satellite images for 24 April to 15 May from 2000 to 2006 to depict persistent snow cover occurring at the end of the wolverine's reproductive denning period throughout the circumboreal region. There are 3 grids contained in this package, each of which corresponds to a distinct portion of the region: (1) North America, (2) Scandinavia and Eurasia, and (3) Southern Europe. Each MODIS image was re-classified into 4 cover classes (snow, bare ground, cloud, night) for each of the 7 years. A portion of each daily MODIS image was typically obscured by clouds or, occasionally, by night. Generating cloud- and night-free images required compositing the 21 consecutive daily images from 24 April to 15 May. If grid cells were classified as bare ground for any day within this time period, they were retained as bare ground in the final coverage. This resulted in a final late-spring snow cover layer that was limited to areas with snow cover that persisted through 15 May. We then summed all annual snow layers for the 7-year period to create a coverage that depicted the number of years out of 7 that each pixel was classified as snow (hereafter, the late-spring snow coverage). Regions of persistent glaciation (e.g., Greenland), and arctic regions >=80° N latitude, were excluded from the late-spring snow coverage due to predictably consistent snow cover during that time of year.These coverages were created for the purpose of investigating correlations between the geographic distribution of late-spring snow cover and the geographic distribution of wolverines throughout the circumboreal region during the period of time that encompasses the end of the wolverine's reproductive denning period.The results of this research are presented in Copeland et al. (2010) and users of this raster dataset should refer to that publication for additional details.

These data were published on 07/02/2024. Minor metadata updates were made on 07/30/2024.

本数据发布包含采用 MODIS（中分辨率成像光谱辐射计）分类卫星图像于 2000 年至 2006 年 4 月 24 日至 5 月 15 日期间所开发的栅格数据集（GeoTiff 格式），旨在描绘北极地区狼繁殖洞穴期结束时的持续性积雪覆盖。该数据包包含 3 个网格，每个网格对应区域的不同部分：（1）北美，（2）斯堪的纳维亚和欧亚，（3）南欧。每个 MODIS 图像均被重新分类为 4 个覆盖类别（雪、裸地、云、夜间）以涵盖 7 年的每一年。通常，每天 MODIS 图像的一部分会被云层遮蔽，偶尔也会在夜间。生成无云和夜间的图像需要组合 4 月 24 日至 5 月 15 日连续 21 天的每日图像。在此时间段内，如果网格单元被分类为裸地，则它们在最终覆盖层中保持为裸地。这导致最终晚春积雪层仅限于 5 月 15 日之前仍存在积雪覆盖的区域。然后，我们将 7 年期间的所有年度积雪层相加，以创建一个覆盖层，描述每个像素在 7 年中被分类为雪的年数（以下简称晚春积雪覆盖率）。由于该时段的积雪覆盖预测性一致，因此排除了持续性冰川区域（例如，格陵兰岛）和北极地区≥80°N 纬度的地区。这些覆盖层是为了研究晚春积雪覆盖的地理分布与狼在北极地区整个繁殖洞穴期结束期间的地理分布之间的相关性而创建的。该研究的成果在 Copeland 等人（2010 年）的论文中呈现，使用此栅格数据集的用户应参考该出版物以获取更多信息。

这些数据于 2024 年 7 月 2 日发布。于 2024 年 7 月 30 日进行了少量元数据更新。