煤矿开采是最重要的甲烷排放源, 然而其排放清单的准确性很低, 一个关键的原因在于缺乏精准识别和定位该类排放源的能力。近年来, 前沿研究表明可以利用卫星高光谱数据反演高分辨率的甲烷异常, 从而帮助识别排放源。但是, 在地表类型复杂地区该算法会完全失效。针对这一问题, 率先提出一种基于 L1 重加权和迭代收缩阈值算法 (ISTA) 匹配滤波器的算法。利用高分五号 (GF-5) 数据在山西地区的实验表明, 该方法性能显著优于现有的其他方法。实验中, 本方法识别出 23 个甲烷强点源, 这些点源全部位于 TROPOMI 的甲烷高值区内, 且高分辨遥感影像显示这些点源处存在典型的煤矿开采设施。该方法的提出为利用 GF-5 卫星数据在世界范围实现甲烷点源排查奠定了技术基础。

Coal mining is the most important methane emission source, yet a key reason for the low accuracy of its emission inventories is the lack of capability to accurately identify and locate this type of emission source. In recent years, cutting-edge research has shown that it is possible to use satellite hyperspectral data to invert high-resolution methane anomalies and thus help to identify emission sources. However, this algorithm will fail completely inareas with complex surface types. To address this problem, the paper proposes the L1 reweighted iterative shrinkage thresholding algorithm (ISTA) matched filter algorithm for the first time. Experiments in Shanxi region using GF-5 advanced hyperspectral imager (AHSI) data show that the performance of the modified method is significantly better than that of the other existing methods. In the experiments, this method identifies 23 strong methane point sources, all of which are located in the methane high value area of TROPOMI, and the high-resolution remote sensing images also show the presence of typical coal mining facilities at these point sources. This method has laid a technical foundation for the worldwide implementation of methane point source identification using GF-5 AHSI data.