布加岗日地区冰川1994—2016年雪线变化及其影响因素分析  

Analysis of the Snow Line Change and Its Influencing Factors in the Glaciers in Bugyai Kangri Region from 1994 to 2016

作　　者：吴仁哲 黄心茹 李勇 李名语 孙涛 王晓文 刘国祥 WU Renzhe;HUANG Xinru;LI Yong;LI Mingyu;SUN Tao;WANG Xiaowen;LIU Guoxiang(Faculty of Geosciences and Environmental Engineering,Southwest Jiaotong University,Chengdu 611756,China)

机构地区：[1]西南交通大学地球科学与环境工程学院,四川成都611756

出　　处：《测绘地理信息》2023年第6期78-82,共5页Journal of Geomatics

基　　金：国家重点研发计划(2017YFB0502700);国家自然科学基金面上项目(41771402);国家自然科学基金青年基金(41804009);四川省科技支撑计划应用基础面上项目(20YYJC4292)。

摘　　要：雪线的高度分布变化常作为冰川的标志线,反映了冰川积累和消融物质平衡盈亏的分布。为了快速、准确地获取雪线分布信息,以时序星载多光谱遥感影像为数据源,从光谱像元灰度的梯度变化出发,提出了一种基于绿色波段像元灰度信息的自适应遥感影像分割方法,并以此估算雪线的高度变化。为验证方法的可行性,选取布加岗日冰川作为典型研究区,使用1994—2016年间的6景多光谱Landsat卫星遥感数据开展实验。研究结果表明,近20余年间,布加岗日冰川雪线高度存在持续上升趋势,且在空间分布上呈现东低西高的分布规律,这也侧面印证了东坡冰川降水量大幅小于西坡;在雪线时空变化方面,布加岗日冰川东坡雪线的升高速率明显高于西坡,抬升最快、最慢和平均速度分别为19.75 m/a、1.26 m/a、10.13 m/a。该方法和结果可为冰冻圈相关研究提供参考和借鉴。The change in the height distribution of the snow line is often used as the marker,reflecting the balance distribu⁃tion of the glacier accumulation and ablation material.In this paper,starting from the gradient change of spectral pixel gray scale,an adaptive remote sensing image segmentation method based on green band pixel gray information is proposed accord⁃ing to the time sequence spaceborne multispectral remote sens⁃ing image as the data source.Thus,to obtain the snow line distribution information quickly and accurately,the height change of the snow line can be estimated by this method.To verify the feasibility of the method,the Bugyai Kangri Glacier was selected as a typical study area to conduct experiments us⁃ing 6 multispectral Landsat satellite remote sensing images ob⁃tained from 1994 to 2016.The results of the study show that the snow line height of the Bugyai Kangri Glacier has contin⁃ued to rise in the past 20 years,and the spatial distribution is low in the east and high in the west,which also confirms that the glacier precipitation of the east slope is much less than that of the west slope.In terms of the spatial and temporal varia⁃tion,the rising rate of snow line on the east slope of the Bug⁃yai Kangri Glacier is significantly faster than that on the west slope,with the fastest,slowest and average speeds of 19.75 m/a,1.26 m/a,and 10.13 m/a,respectively.Therefore,the method and results of this study can provide reference for the related research of the cryosphere.

关 键 词：雪线提取 Landsat卫星 阈值分割 自适应遥感影像 

分 类 号：P237[天文地球—摄影测量与遥感]