极地研究2025，Vol.37Issue(2)：171-188,18.DOI:10.13679/j.jdyj.20240037
基于ICESat-2数据的东南极Drygalski冰舌崩解前干舷特征提取
Freeboard mapping and characterization of Drygalski Ice Tongue,East Ant-arctica prior to calving based on ICESat-2 data
摘要
Abstract
Freeboard is a key variable for estimating the thickness and volume of Antarctic ice tongues and its changes can indirectly indicate the growth,stability,and disintegration process of ice tongues.In early 2022,the Drygalski Ice Tongue(hereafter referred to as DIT)in the Ross Sea area of the East Antarctic underwent calving event.However,data on the outflow altitude of the DIT on the eve of disintegration are still lacking,and the characteristics of the change in outflow altitude are still unclear,which poses a challenge for in-depth study of the disintegration process of the DIT.In this study,a new freeboard extraction technique is developed based on ICESat-2/ATLAS data(mainly including the initial elevation calculation of the free-board,correction of the measurement footprint,correction of the interannual variation of the freeboard,and interpolation of the data to form a map),to extract the freeboard and its distribution characteristics of the DIT on the eve of its disintegration,and to evaluate the accuracy of it by using a REMA DEM.The free-board extraction results show that the DIT has a thick freeboard distribution upstream of the DIT,which gradually thins along the flow direction of the ice tongue,showing significant basal channel characteristics;the DIT drywall is in good agreement with the REMA DEM(R=0.86,ERMSE=3.92 m),but overestimates most of the freeboard of the thin ice(<10 m).The methodology of this study is expected to be equally a p-plicable to satellite remote sensing inversions of freeboard of other ice tongues and ice shelves,and will make an important contribution to the understanding of Antarctic ice tongue disintegration mechanisms and the study of Antarctic mass balance.The methodology of this study can be used as a reference for satellite remote sensing inversion of the freeboard of ice shelves of other Antarctic ice tongues,and to gain insights into the calving mechanisms and mass balance of Antarctic ice tongues.关键词
南极/冰舌干舷/冰舌崩解/卫星遥感/ICESat-2Key words
Antarctica/ice tongue freeboard/ice tongue calving/satellite remote sensing/ICESat-2引用本文复制引用
郭怡心,王显威..基于ICESat-2数据的东南极Drygalski冰舌崩解前干舷特征提取[J].极地研究,2025,37(2):171-188,18.基金项目
国家自然科学基金面上项目(42276237)和上海交通大学深蓝计划配套项目(SL2022PT205)资助 （42276237）
