利用改进的亮温日较差法探测格陵兰冰盖表面融化  

Surface Melting Detection of the Greenland Ice Sheet Using Advanced Diurnal Amplitude Variations Algorithm

作　　者：肖倩雨 周春霞[1,2,3] 刘勇 XIAO Qianyu;ZHOU Chunxia;LIU Yong(Chinese Antarctic Center of Surveying and Mapping,Wuhan University,Wuhan 430079,China;Hubei Luojia Laboratory,Wuhan,430079,China;Key Laboratory of Polar Surveying and Mapping,Ministry of Natural Resources,Wuhan 430079,China)

机构地区：[1]武汉大学中国南极测绘研究中心,湖北武汉430079 [2]湖北珞珈实验室,湖北武汉430079 [3]自然资源部极地测绘科学重点实验室,湖北武汉430079

出　　处：《武汉大学学报（信息科学版）》2024年第10期1931-1939,共9页Geomatics and Information Science of Wuhan University

基　　金：国家自然科学基金(42171133,41941010);国家重点研发计划(2021YFC2803303);湖北省自然科学基金(2019CFA057)。

摘　　要：格陵兰冰盖是全球海平面上升的主要贡献源之一,其表面融化和融水径流引发的物质损失约占冰盖总物质损失的60%,研究格陵兰冰盖的表面融化具有重要意义。采用2019年增强分辨率的专用微波成像仪37 GHz垂直极化被动微波数据,提出改进的亮温日较差(advanced diurnal amplitude variations,ADAV)方法,并利用该方法探测格陵兰冰盖的表面融化。与自动气象站的气温数据对比,ADAV方法使用动态阈值探测结果的平均精度高于使用固定阈值的传统日较差方法,且被动微波数据时间对探测精度无明显影响。采用该方法分析格陵兰冰盖冻融发现,2019年冰盖融化天数最多达165 d,7月31日融化面积达到最大,占冰盖总面积的67%;夏季3次出现融化峰值,且南部沿岸发生了冬季融化事件。Objectives:The Greenland ice sheet is one of the main contributors to the global sea level rise,and the mass loss caused by its surface melting and meltwater runoff accounts for about 60%of the total mass loss of the ice sheet,so it is of great significance to study the surface melting of the Greenland ice sheet.Methods:Based on the 37 GHz vertical polarization passive microwave data of special sensor microwave imager sounder,the advanced diurnal amplitude variations(ADAV)method is proposed to detect the surface melting of the Greenland ice sheet.Results:Compared with the air temperature data of automatic weather stations,the average accuracy of the detection results of the ADAV method using dynamic threshold is better than that of the traditional diurnal amplitude variations method using a fixed threshold,and the passive microwave data time has no obvious influence on the detection accuracy.Conclusions:The freezethaw analysis of the Greenland ice sheet based on this method found that in 2019,the area with the most melting days on the ice sheet melted up to 165 d.The melting area reached the maximum on July 31st,accounting for 67%of the total ice sheet area.Three melting peaks arose in summer,and there were several winter melting events on the south coast.The ADAV method and its application to high spatial resolution passive microwave data have promoted the development of refining ice sheet freezing and thawing observations.

关 键 词：格陵兰冰盖 表面融化 改进的亮温日较差法 Rosin阈值 Ramage阈值 

分 类 号：P237[天文地球—摄影测量与遥感]