Snow is a significant component of the ecosystem and water resources in high-mountain Asia (HMA). Therefore, accurate, continuous, and long-term snow monitoring is indispensable for the water resources management and economic development. The present study improves the Moderate Resolution Imaging Spectroradiometer (MODIS) onboard Terra and Aqua satellites 8 d (“d” denotes “day”) composite snow cover Collection 6 (C6) products, named MOD10A2.006 (Terra) and MYD10A2.006 (Aqua), for HMA with a multistep approach. The primary purpose of this study was to reduce uncertainty in the Terra–Aqua MODIS snow cover products and generate a combined snow cover product. For reducing underestimation mainly caused by cloud cover, we used seasonal, temporal, and spatial filters. For reducing overestimation caused by MODIS sensors, we combined Terra and Aqua MODIS snow cover products, considering snow only if a pixel represents snow in both the products; otherwise it is classified as no snow, unlike some previous studies which consider snow if any of the Terra or Aqua product identifies snow. Our methodology generates a new product which removes a significant amount of uncertainty in Terra and Aqua MODIS 8 d composite C6 products comprising 46 % overestimation and 3.66 % underestimation, mainly caused by sensor limitations and cloud cover, respectively. The results were validated using Landsat 8 data, both for winter and summer at 20 well-distributed sites in the study area. Our validated adopted methodology improved accuracy by 10 % on average, compared to Landsat data. The final product covers the period from 2002 to 2018, comprising a combination of snow and glaciers created by merging Randolph Glacier Inventory version 6.0 (RGI 6.0) separated as debris-covered and debris-free with the final snow product MOYDGL06*. We have processed approximately 746 images of both Terra and Aqua MODIS snow containing approximately 100 000 satellite individual images. Furthermore, this product can serve as a valuable input dataset for hydrological and glaciological modelling to assess the melt contribution of snow-covered areas. The data, which can be used in various climatological and water-related studies, are available for end users at https://doi.org/10.1594/PANGAEA.901821 (Muhammad and Thapa, 2019).
Sher Muhammad
从2013年至2014年，对黑河上游高海拔地区晚第四纪冰川地貌进行了考察采样。通过野外考察结合遥感影像得到了摆浪河上游山脊附近各级冰碛陇的分布图。
胡小飞, 潘保田
葫芦沟小流域2012.7.21-9.2冰川前沿融雪水温度及近地表温度观测数据，HOBO自动温度记录仪观测，观测频率为1次/15分钟，近地表温度记录仪距地表20cm。 01观测点为冰湖，由湖南坡永久性积雪补给形成，湖泊近似呈三角形，长边走向与坡脚平行，坐标为99°53′11″E,38°13′6″N。观测时段2012.7.21-2012.9.2。 02号观测点位于冰湖下方，葫芦沟东支流上游发源处，永久性积雪坡脚处，融雪下缘。坐标为99°53′12″E,38°13′6″N。观测时段2012.7.21-2012.9.2。 两点距离较近，近地表温度为统一的温度，为01号点近地表温度。
常启昕
冰川对气候变化反应灵敏，是全球变化重要的指示器和放大器。在内陆河地区，河川径流主要来自于高山冰雪融水，冰川是这些地区非常重要的“固体水库”，冰川融水是黑河各支流重要的补给来源。 黑河流域冰川编目完成于1979-1980年，相关信息可参考王宗太等编著的《中国冰川目录-祁连山区》。2004年《中国冰川目录》相关成果经过系统数字化处理，建立了数据库，最终成果通过《中国冰川信息系统》发行。但在坐标恢复过程中参考资料精度较差，黑河流域的冰川分布图带有明显的位置偏移，因此我们又利用正射几何校正的Landsat遥感影像进行了校对。处理后的黑河冰川分布数据在几何精度上与我国现有的基础地理信息保持高度一致，在属性上与第一次冰川编目保持一致。
王宗太
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