海面溢油光学卫星遥感监测能力分析

 海面溢油对海洋生态的影响具有频率高、范围广和危害大的特点。卫星遥感已成为海面溢油监测的重要手段。本文从海面油膜光谱特性出发,与常用的光学卫星传感器建立对应关系,根据对不同光学遥感卫星的空间分辨率、时间分辨率、幅宽和波段数等主要物理参数的对比分析认为,MODIS传感器和HJ-1卫星有较强的海面溢油监测能力。故此,采用MODIS、BJ-1、HJ-1和FY-3光学卫星影像,对2006年3月和2011年6月渤海海面溢油污染事故进行了遥感监测。MODIS遥感图像可以清晰反映出2006年和2011年这2次溢油污染事故中海面油膜信息,HJ-1卫星遥感影像则能反映出2011年溢油污染事故中海面油膜信息,而BJ-1和FY-3卫星遥感影像不能反映出海面油膜信息。HJ-1、BJ-1和FY-3卫星在波段设置上相似,但是,BJ-1和FY-3卫星不能反映出油膜信息,所以,本文进一步对这2次溢油事件中的MODIS遥感影像的油水光谱反差和海水光谱方差进行计算,并对结果进行比较分析,实验结果表明,当MODIS某一波段的海水光谱方差小于油水光谱反差时,则该波段可以显示出油膜信息;而当油水光谱反差小于或接近海水方差时,则不能反映出海面油膜信息。从波谱响应、空间分辨率和时间分辨率,以及监测实例中说明MODIS传感器有较强的海面溢油监测能力。

Optical Satellite Remote Sensing Capabilities Analysis of the Marine Oil Spill

The marine oil spill impacts on the marine environment with the features of high frequency,wide range and great hazards.Using remote sensing for marine oil spill detection has become an important means.In this paper,we started with the spectral character of the marine oil spill,and established the relationship with the common optical satellite sensors.Then we analyzed the main physical parameters of the different optical satellites,including the spatial resolution,the time resolution,width and band number.The MODIS sensor and HJ-1 satellite has a strong monitoring capabilities of marine oil spill.Based on this,we used MODIS,BJ-1,HJ-1 and FY3 optical satellites images to monitor the marine oil spill accident occurred in the Bohai Sea in March 2006 and June 2011.The MODIS image can reflect the information of marine oil spill clearly in 2006 and 2011.The HJ-1 image can reflect the information of marine oil spill clearly in 2011,but the BJ-1 and FY-3 images cannot reflect the information of marine oil spill clearly in the two oil spill accidents.HJ-1,BJ-1and FY3 satellites in the band set are similar,but the BJ-1 and FY-3 satellites cannot reflect the information of marine oil spill.So in this article we compared the contrast of oil-water spectrum and the variance of the sea water spectrum using the MODIS remote sensing data.Experimental results show that,when the variance of the sea water spectrum is less than the contrast of oil-water spectrum in the MODIS band,the oil spill information can be shown on this band clearly.When the contrast of oil-water spectrum is less than or close to the variance of the sea water spectrum,the oil spill information cannot be shown on this band clearly.So through the above analysis,the MODIS sensor has a strong monitoring capacity on the spectral response of oil spill,spatial resolution,temporal resolution and the instance.This article has certain practical value of the optical satellite selected in marine oil spill remote sensing monitoring.