Airborne Hyperspectral Remote Sensing Of Red Tide And Oil Pollution Of Water Body Information Extraction

In recent years, large damage has been brought to the economic of the near shore part of our country by the frequently occurred oil pollution and red tide. As a much more important manner oceanic monitoring than any other remote sensing method, Pushbroom Hyperspectral Imager (PHI) can obtain large sum of high resolution and continuous hyperspectral data. In 2001, State Oceanic Administration sets up the task that study Red Tide using Hyperspectral Remote Sensing Technique. This is the first time for China to monitor marine red tide and oil pollution by using remote hyperspectral technique. In this paper ,PHI and its oceanic application are studied and many methods are studied by analyzing the hyperspectral data which are obtained above the North China Sea by aeroplane from July to August in 2001: 1. The oil pollution water and red tide water reflectance curve obtaining method and its spectrum feature analysis. In this part, several methods of radiance-reflectance transformation have been discussed and analyzed and reflectance curves of oil pollution water and red tide water has been obtained by using the method of Internal Average Relative Reflectance(IARR). After the reflectance features of normal seawater with oil pollution water and red tide water are analyzed, the red tide characteristic spectrum can be abstracted. And a conclusion has been concluded that the method is available and fitful when there is no atmosphere parameters measured. 2.The identification and classification of oil pollution and red tide water using the data. The classification images of oil pollution and red tide are obtained and analyzed in this part by using the method of Spectral Angle Mapper. 3. Image fusion of hyperspectral data. The color images are created and analyzed by finding three images of different channel using the methods of Principal Component Analysis and the calculation of united entropy 4. The geometric features of the hyperspectral image extracting method. After finding the gray image which is of the most information, the method and algorithm is determined to make binary image and trace the edge of the red tide area in order to computer the geometric features such as area, girth and shape factor of the district.