摘要
融雪信息的获取是积雪监测中的一个重要环节,使用遥感手段获取融雪信息有观测范围广、获取信息量大、速度快、实时性好等优势。讨论了使用MOD IS影像数据获取融雪信息的方法,根据研究需要提出了融雪指数SNOWM ELT INDEX(SM I)的概念,从理论上分析了SM I在融雪过程各阶段的变化规律。最后文章以乌鲁木齐市一次完整的融雪过程为例,验证了SM I的下降幅度在融雪过程中随着积雪中的液态水含量的增多而逐渐减少,并最终停留在一个较低水平上的变化规律。
To observe snowmelt information is an important part of snow observation. Using Remote Sensing methods to observe snowmelt information has many advantages, such as large area of observation, abundant information of receiving, high speed to acquire information and real time of observation etc. In this paper, we present the method of observing snowmelt information by using MODIS images. Based on Snow and water spectral curves under different status, we propose the concept of snowmelt index （SMI） through MODIS band 4 and band 5, and then analyze variation law of SMI in each stage of snowmelt from snowmelt theories and discipline of absorption by snow, melted snow and water. At the end, we take Urumchi in Xinjiang province as the case study, analyze the whole snowmelt process between winter in 2002 and spring in 2003, use the snow depth, days of snow, temperature in local area to simulate snowmelt map in the field since there is no snowmelt map observed directly, and then compare the snowmelt map with SMI map in the corresponding time span. Finally, we validate the law, which is proposed in this paper that the decline rate of SMI becomes small when the content of water in snow increases, and at last stay at a low value.
出处
《遥感技术与应用》
CSCD
2006年第1期37-40,共4页
Remote Sensing Technology and Application
基金
国家高技术研究发展计划(NO.2003AA135010)资助
