中国地区冬季积雪遥感监测方法改进

IMPROVED REMOTE SENSE MONITORING ON SNOW COVER OF CHINA IN WINTER

该文概述了卫星遥感积雪监测原理,介绍了积雪判识方法,对国家卫星气象中心已有的业务化极轨气象卫星冬季旬积雪监测算法和流程进行了改进。经过比对,设计了新的可见光太阳天顶角订正模式,针对NOAA-16／AVHRR3和FY-1D／MVISR重新确定了积雪判识变量及相应的动态积雪检测阈值,提出了概率积雪判识方法,结合多光谱阈值法建立了概率结合阈值(Probability Combined with Threshold,PCT)的积雪判识方法,并以该算法为基础建立了新的业务化积雪动态遥感监测系统。同时,用新算法对部分历史产品重新做了处理,并简要分析了1996至2003年中国地区冬季积雪分布特征。

This paper describes theory and technique about snow cover monitoring. National Satellite Meteorological Center (NSMC) has been doing remote sense monitoring on snowpack of China in winter every ten-day, about which some improvement has been made here on the procedure and flow. A new mode of solar zenith correction is designed for visible light by comparison. Some judgement variables are reset and accordingly the thresholds are adjusted in snow cover monitoring according to NOAA-16/AVHRR3 and FY-1D/MVIRS data. Especially, snow probability is stated and an effective method of distinguishing snowpack, Probability Combined with Threshold (PCT), is put forward, based on which a new operational system of snow cover monitoring is established. Finally, some products are rehandled and the feature of winter snow cover distribution in China, from 1996 to 2003 is analysed.