摘要
青藏高原又称世界“第三极”,是北半球中低纬度地区最大的现代冰川作用区,在全球气候系统中起着至关重要的作用。研究该地区冰川流速时空变化对于认识冰川动力学特征,及其对气候变化的响应具有重要的意义。而且长期冰川活动性监测对推动区域可持续发展、促进全球生态环境保护具有重要的指导作用。本文基于2019–2020年间覆盖目标区域典型冰川的高分三号(GF-3)影像,借助改进的偏移量跟踪算法,通过精准地弥补全局性位移和地形效应以及滤波降噪处理后,得到了高亚洲地区典型冰川表面高精度运动数据集(GeoTIFF格式,32位浮点型)。采用GF-3卫星FSI成像模式SAR影像,计算结果空间分辨率约为12 m。非冰川区残差统计分析表明,研究周期内整体精度约为0.5 m。结果显示,研究区冰川表面运动大多呈现为积累区速度较快/消融区和末端运动速度慢的特点,个别中小型冰川具有相对较强的活动性,整体上与地势起伏和气候等因素存在一定的相关性。本数据集可作为青藏高原冰川物质平衡分析的基础数据,支撑高亚洲地区气候变化方面的研究,推动国产遥感数据在冰川活动性及气候变化研究中的深层次应用。
The Qinghai-Tibet Plateau,also known as the world’s“Third Pole”,is the largest modern glaciation region in the middle and low latitudes of the Northern Hemisphere,which plays an important role in the global climate system.It is of great significance to study the spatiotemporal changes of the glacier motion for understanding the dynamic characteristics of glaciers and its response to climate change.Besides,the long-term monitoring of glacier activity on the Qinghai-Tibet Plateau plays an important guiding role in promoting regional sustainable development and global ecological environment protection.This dataset is based on the SAR imagery of the High Mountain Asia acquired by GF-3 from 2019 to 2020.We adopted an improved pixel-tracking algorithm for calculation to obtain the dataset(GeoTiff format in 32-bit floating-point)of the distribution of glacier surface motion by precisely removing the global deformation,the topographic-related offset and the effect of the high-frequency noise.We sampled the SAR image of GF-3 satellite FSI imaging mode to keep the spatial resolution of the results around 12 m.The statistical analysis of the residual movement in the non-glacial region indicates that the overall accuracy is about 0.5 m.The results indicate that the glacier motion in the accumulation area is generally faster than that in the terminal or ablation part,and some small and medium-sized glaciers have relatively strong activities.Generally,the glacier surface motion reveals a positive correlation with topography and climate.The dataset can serve as the basis in the research on glacial mass balance in Qinghai-Tibet Plateau,provide statistical support to understand the relationship between ice and climate change in High Mountain Asia,and promote the in-depth application of domestic remote sensing data in glacier activity and climate change.
作者
张齐民
吕明阳
闫世勇
ZHANG Qimin;LYU Mingyang;YAN Shiyong(School of Environment Science and Spatial Informatics,China University of Mining and Technology,Xuzhou 221116,P.R.China;Key Laboratory of Digital Earth Science,Aerospace Information Research Institute,Chinese Academy of Sciences,Beijing 100094,P.R.China)
基金
国家对地观测科学数据中心(NODAOP2020010)。
