Sentinel-2 MSI卫星数据在水体信息提取中的应用

为实现水灾发生后淹没区域的快速监测,为受灾地区的灾情评估、调查及水资源管理提供依据,借助Sentinel-2 MSI卫星对乌海湖、黄河宁夏石嘴山河段、沙湖3个研究区域2018年7—10月强降水前后水位、水体面积进行了动态监测。结果表明,乌海湖10月中旬之前水体面积持续增大,之后出现下降;黄河石嘴山部分河段在7月强降水之后河道变宽,10月中旬宽度达到最大;沙湖面积在丰水期趋于稳定,平水期部分缩减。基于Sentinel-2 MSI改进归一化差异水体指数(MNDWI),结合Otsu算法可以快速准确提取水体信息。

Application of Sentinel-2 MSI Satellite Data in Water Body Information Extraction

In order to achieve rapid monitoring of the inundation area after flood occurrence,it provides a basis for disaster assessment,investigation,and water resources management in the affected areas.The Sentinel-2 MSI satellite was used to dynamically monitor the water level and water area of the Wuhai Lake,the Yellow River Shizuishan section,and the Shahu Lake before and after heavy precipitation period from July to October in 2018.The results show that the water body area of Wuhai Lake continue to increase before mid-October,and then decrease.The river section of the Yellow River Shizuishan is widened after heavy precipitation in July,and the width reach the maximum in mid-October.Shahu Lake is stable during high water period and reduces partially during flat water period.Based on the Sentinel-2 MSI satellite data,the modified normalized difference water index(MNDWI)combined with the Otsu algorithm can quickly and accurately extract water information.