高分三号山地冰川表面运动提取与分析

冰川表面运动提取在冰川动力学与物质平衡变化研究中具有重要意义。针对当前我国自主遥感卫星数据在冰川运动监测应用中存在的不足，选用GF-3卫星FSI模式下获取的2019—2020年间覆盖亚洲高山区典型冰川的SAR数据，借助并行化偏移量跟踪算法获取了研究区冰川表面流速分布。研究结果表明：优化后的偏移量跟踪算法极大地提高了运行效率；全局形变拟合估计、地形偏差校正及滤波降噪后，冰川运动分布形态更加直观，精度可达0.5 m；通过与准同期Landsat-8影像提取的冰川流速对比以及对非冰川区位移残差的统计分析，验证了GF-3影像在监测不同区域冰川流速结果方面的可靠性及适用性；GF-3影像凭借其良好的空间分辨率，在规模较小、运动缓慢的冰川运动提取方面具有显著的优势，能够更好地体现冰川运动细节信息及其差异性。该研究有助于分析气候变化背景下青藏高原地区冰川的运动规律及其时空演变特征。

Accurate extraction and analysis of mountain glacier surface motion with GF-3 imagery

Accurate extraction of glacier movement holds special significance in the analysis of the glacier dynamics and mass balance. There is few research of glacier movement with Chinese high-quality remote sensing images in High Mountain Asia. In this paper， based on the SAR imagery of the High Mountain Asia acquired by GF-3 with FSI imaging modes， the distribution of ice surface motion is obtained with GPU parallel algorithm pixel-tracking algorithm from 2019 to 2020. The results demonstrate that the operating efficiency was greatly improved. The accurate ice motion with an accuracy of 0.5 m was extracted by removing the global deformation， the topographic-related offset and the noise. The glacier flow velocity was assessed by the results of quasi-same period Landsat-8 data and the statistical analysis of the residual movement in the non-glacial region， then the usability and applicability of GF-3 data in monitoring glacier motion was evaluated. Because of the high spatial resolution， GF-3 satellite imagery plays a unique advantage in monitoring the glacier motion on the small-sized and slow-moving glaciers， which could better reflect the detailed information of glacier movement and corresponding variation. Furthermore， the accurate extraction of glacier surface movement in Qinghai-Tibet Plateau region would provide better insight into the spatiotemporal evolution of glaciers and global climate change.