EASE-Grid投影风云卫星产品地理信息写入方法

Geographic Information Writing Method of Fengyun Satellite Products Based on EASE-Grid Projection

风云卫星遥感数据服务网的卫星遥感产品数据集中,风云三系列气象卫星遥感产品数据集中很多采用的是等面积可伸缩地球网格(EASE-Grid)投影方式进行处理,实际应用中对使用者具有较高的数据处理能力要求,不利于遥感产品数据集的省级应用。基于数据集使用中的这些问题,该文以FY3D雪水当量数据集产品为例,采用程序化方法对EASE-Grid投影产品数据集的地理信息进行写入,通过构建地理坐标系参考对象和地理信息目录,将数据矩阵中写入地理信息并以GeoTiff格式文件输出。结果表明,经过该方法处理过的产品数据可与矢量文件实现准确的经纬度信息的匹配,降低了数据分析处理的难度。该方法具有较好的适用性,对于EASE-Grid的三种不同的投影方式均适用,可在一定程度上提高卫星遥感产品数据集的省级科研与应用水平。

Many of the FY-3 series meteorological satellite remote sensing product datasets in Fengyun Satellite Remote Sensing Data Service Network are processed using the Equal-Area Scalable Earth Grid(EASE-Grid)projection method,which requires high data processing capability for users in practical applications,and is not conducive to the provincial application of remote sensing product datasets.To address these issues,taking the snow water equivalent(SWE)datasets of FY3D as an example,we propose a method of geographic information writing in EASE-Grid projection product datasets using the programming.By constructing reference raster cells to geographic coordinates(GeographicCellsReference)and geographic information directory(GeoKeyDirectoryTag),geographic information is written into the data matrix and output in GeoTIFF format.The results show that the product data processed by the proposed method can accurately match with the vector files in terms of geographic information,reducing the difficulty of data analysis and processing.The proposed method is applicable to all three different projection methods of EASE-Grid and can improve the provincial-level scientific research and application of satellite remote sensing product datasets.