基于SAR偏移量跟踪法提取岗纳楼冰川流速

Extraction of Gangnalou glacier velocity based on SAR migration tracking method

冰川动态变化监测有助于反映全球和区域气候演变,保护自然环境和自然资源。近年来,基于SAR数据研究冰川运动已成为主流技术之一。基于SAR提取冰川流速主要包括合成孔径雷达干涉测量、多孔径雷达干涉和偏移量追踪法。本文采用SAR偏移量追踪法中的强度追踪法,提取青海省哈拉湖东北部岗纳楼冰川沿距离向、方位向的冰川流速。试验结果表明,距离向冰川运动速度提取效果较好,最大流速达15.36 m/a,流速从中轴向两侧递减,在冰舌末端趋于0;方位向提取的冰流速最大达18.27 m/a,但因电离层干扰,方位向流速图中存在一些方位向条纹。此外,由于冰流速在方位向分量小等因素的影响,本文研究提取的方位向流速精度低于距离向。

Glacier dynamic change monitoring helps to reflect global and regional climate change and protect the natural environment and natural resources.In recent years,the research on glacier movement based on SAR data has become one of the mainstream technologies.The extraction of glacier velocity based on SAR mainly includes synthetic aperture radar interferometry,multi-aperture radar interferometry and offset tracking.In this paper,the intensity tracking method of SAR migration tracking method is used to extract the glacier velocity along the distance and direction of Gangnalou glacier in the northeast of Hala lake,Qinghai province.The results show that the extraction effect of the range direction glacier velocity is better,the maximum velocity reaches 15.36 m/a,the velocity decreases from both sides of the central axis,and tends to 0 at the end of the ice tongue;the maximum velocity of the azimuth direction extraction ice velocity reaches 18.27 m/a,but there are some directional streaks in the azimuth velocity diagram due to the ionosphere interference.Inaddition,due to the small component of ice velocity in azimuth and other factors,the accuracy of azimuth velocity extracted in this study is lower than that in distance.