NOAA／AVHRR数据的雪盖信息提取与复合

Extracting the Information of Snow-cover from NOAA/AVHRR Data and Overlaying with Vector Data

在对ＮＯＡＡ／ＡＶＨＲＲ数据特征与雪冰波谱特性分析的基础上，对各种提取雪盖信息的方法进行了比较，指出了各种方法的优劣，认为在实时的雪灾监测与评估系统中，直方图分割的方法快速有效。另一方面，通过雪盖影像与ＧＩＳ中各种矢量图形的复合配准实验，指出宜先对ＡＶＨＲＲ影像进行点位计算，然后利用控制点进行精校正，所产生的图像才能达到与矢量图形的准确配准。

The methods of extracting the information of snow-cover from NOAA/AVHRR data,geometric Correction of the snow-cover image,the overlaying with vector file and formatcoriversion of image data were introduced in this paper.The different advantages and suit-able extents of each methods were described based on comparison of several classifiedmethods and accuracy analysis of silow information,Meanwhile,author pointed out thathistogram density spliting is a fast and effective way of extracting snow-cover informationand suited to tise in the system of snow disaster for monitoring and assessment.The ex-periment result also showed that the calculation of pixel position and the accurate geomet-ric correction of AVHKR image must be finished before overlaying with vector data.Thenext research to obtain accurate snow information using synthetic temperature radar data andmethods of atmosphere and terrain correction was discussed at the end of this paper.