摘要
由于云与雪具有类似的辐射特性——高反射率与低亮度温度,利用目前的业务气象卫星扫描辐射计资料,用客观方法识别单个像素所对应的是雪还是云仍是一个十分困难的问题。本文利用NOAA-9和NOAA-11日间所有5个通道的AVHRR资料,分析了中国的西部——青藏高原及戈壁、沙漠等地区云和地表雪的多通道辐射特征,并采用多阈值法,结合实例进行了云、雪及背景地表的识别分类试验。分析结果表明,AVHRR第3通道的测量值经过适当处理后对识别云和地表积雪是十分有意义的。
All five AVHRR channels data of NOAA-9 and NOAA-11 are used to extract the multispectral properties of cloud, snow and land surface over the west of China—including Qinghai-Xizang Plateau and desert area. An algorithm for cloud and snow detection is developed based on the multi-threshold method. It is shown that the 3.7 μm (channel 3) measurements are significant for cloud and snow detection as some authors have pointed out. Some tests of this algorithm applied to Qinghai-Xizang Plateau have shown reasonable classification results.
出处
《高原气象》
CSCD
北大核心
1991年第4期371-380,共10页
Plateau Meteorology
关键词
云
积雪
多通道
卫星
识别
Cloud
Snow
Satellite detection.