新疆北部AMSR2雪深产品降尺度算法及验证  

Downscaling Algorithm and Verification of AMSR2 Snow Cover Depth Products in North Xinjiang

作　　者：邓婕[1] 黄晓东[1] 马晓芳[1] 冯琦胜[1] 梁天刚[1] 

机构地区：[1]兰州大学草地农业科技学院,甘肃兰州730020

出　　处：《干旱区研究》2016年第6期1181-1188,共8页Arid Zone Research

基　　金：国家重点基础研究发展计划"973"计划(2013CBA01802);国家自然科学基金项目(41671330;31372367;31228021);长江学者和创新团队发展计划项目(IRT13019)

摘　　要：以新疆北部为研究区,利用AMSR2雪深标准产品及MODIS逐日积雪面积比例产品,对10 km空间分辨率AMSR2雪深标准产品进行降尺度运算,获得了北疆地区降尺度后的500 m空间分辨率SNDsp雪深产品。利用21个气象台站实测雪深数据对升轨和降轨2个时间的AMSR2雪深标准产品及SNDsp产品进行了精度评价及精度分析。结果表明：降尺度后的SNDsp升轨产品均方根误差较AMSR2雪深标准升轨产品降低了1.78 cm,降轨产品的均方根误差较AMSR2雪深标准产品降低了2.68 cm,且降尺度SNDsp产品与地面台站实测雪深的相关性较AMSR2雪深标准产品在一定程度上有所提高。AMSR2雪深标准产品在雪深为7~9 cm时误差最小,SNDsp产品在雪深为16~18 cm时精度最高。雪深大于12 cm时,AMSR2雪深标准产品精度较低,而SNDsp产品在此基础上精度有了一定程度的提高。Snow cover is an important component of land cover and plays a key role in balancing global energy and water resources because of its high albedo and thermal storage properties. Remote sensing is widely used in monitoring snow cover depth. With increasing demand of many climate models and hydrological models for accurately monitoring snow cover depth parameters,downscaling algorithm can be a good method to improve the accuracy of monitoring regional snow cover depth. In this study,north Xinjiang was regarded as the study area,and the AMSR2 snow cover depth products and MODIS daily cloud-free snow cover area proportion products were used to develop the downscaling algorithm for AMSR2 snow cover depth products,and the 500 m resolution snow depth products for north Xinjiang were produced. The snow cover depth data observed from 21 meteorological stations were used to validate the new products. The results showed that the RMSE was decreased by 1. 78 cm and 2. 68 cm after downscaling in descending and ascending orbit AMSR2 snow depth products,respectively. The correlations between the observed values and the downscaling products in descending orbit of AMSR2 were also improved. The AMSR2 standard snow cover depth products showed a minimum error when snow cover depth varied in a range from7 to 9 cm,and the precision of downscaling products reached to the best when snow cover depth varied in a range from 16 to 18 cm. When snow cover depth was thicker than 12 cm,the precision of AMSR2 standard snow cover depth products was decreased. However,the new product seemed to be much better than the standard one,and the precision was improved in the whole study area.

关 键 词：AMSR2 MODIS 降尺度 雪深 新疆北部 

分 类 号：P407[天文地球—大气科学及气象学]