Abstract: Cloud coverage in daily snow cover products is a main obstacle in using Moderate Resolution Imaging Spectroradiometer (MODIS). In this study, the multitemporal and multisensor combination approaches are applied to reduce cloud obscuration with Aqua Advanced Microwave Scanning Radiometer for NASA’S Earth Observing System (AMSR-E)  snow depth products introduced as the auxiliary data to develop 6 new kinds of snow cover products. Different snow cover duration days(SCD) maps are developed from these combined products. The results are as follows: (1) MODIS and AMSR-E 4-day thresholdcombined snow cover product performed well in algorithm efficiency, cloud-reducing effect and capability in maintaining relatively high spatiotemporal resolutions; (2) Under all weather conditions, the overall, snow and land accuracies of the resulted cloud-free products were 96%, 80% and 99%, and they were significantly higher than 64%, 32% and 70% of the original MODIS Terra and Aqua combination product, respectively; (3) The SCD map generated from this product could not only maintain a high spatial resolution of the original MODIS product, but also could precisely reflect the spatial distribution of the snow cover status in the study area.

Key words: snow covers, product SCD, MODIS, spatial resolution, cloud obscuration reduction, arid area, China