论文部分内容阅读
冰川速度是冰川学研究中的一个重要参数,遥感方法为获取冰川表面速度提供了一种有效的手段。由于慕士塔格峰地区常年有云覆盖,不能为速度提取提供足够多数量的光学影像。但是,基于SAR影像对偏移量的提取算法为该地区冰川流速的测量提供了一个有效的途径。分别获取两幅雷达影像(ALOS/PALSAR)距离向和方位向的偏移,通过信噪比和相关系数选择可信点,然后通过整体拟合的方法去除雷达图像整体偏移,得到与冰川运动相关的偏移信号。首次得到了慕士塔格峰地区冰川表面完整的速度分布情况,依据该地区的速度大小分布特点,对慕士塔格峰四周冰川进行了划分。并进一步分别分析了该地区冰川在距离向和方位向速度大小与地形的关系,表明速度的大小与地形具有直接的相关性。结果表明,基于SAR影像对的偏移量测量为冰川研究提供了一个有效的方法和手段。
Glacier speed is an important parameter in the research of glaciology. Remote sensing method provides an effective means to obtain the glacier surface velocity. Due to the perennial cloud cover in the Muztagtag region, it is not possible to provide a sufficient number of optical images for speed extraction. However, the extraction algorithm based on SAR images provides an effective way to measure glacier velocity in the area. Obtain distance and azimuth offsets of two radar images (ALOS / PALSAR) respectively, select credible points through signal-to-noise ratio and correlation coefficient, and then remove global radar image offset by global fitting, Related offset signal. For the first time, the complete velocity distribution of glacier surface in Muztagata peak area was obtained. According to the distribution of velocity in this area, the glaciers around Muztagata Peak were divided. Furthermore, the relationship between the velocity of the glacier in the distance and azimuth and the terrain is further analyzed respectively, which shows that the magnitude of the velocity is directly related to the terrain. The results show that the displacement measurement based on the SAR image pair provides an effective method and means for glacier research.