摘要
南极数字高程模型(DEM)能够为南极科考活动提供关键地形数据的支撑,还可用于融水池体积估算等研究。但南极自然环境恶劣,传统地面定标方法实施困难,星载激光雷达能够直接获取高精度的地表高程数据,可以有效解决这一问题。ICESat-2作为新一代激光测高卫星,其激光足印间隔仅为0.7 m,其南极冰盖的高程数据产品精度可达厘米级。并且该南极冰盖的高程数据产品与南极洲参考高程模型REMA DEM生成的源数据具有较好的时间匹配度。该文首先利用2015年IceBridge计划的IDHDT4数据产品验证了ICESat-2陆冰高数据ATL06的高程精度。在此基础上,利用验证后的ATL06数据系统评估了REMA DEM 32 m分辨率产品的高程精度。研究表明REMA DEM在坡度小于5°的平坦地形上精度可达亚米级,接近激光测高精度,在坡度达到30°时高程误差的RMSE不超过3.5 m。此外,论文进一步分析了地面光斑轨迹方向与DEM坡向间的夹角和季节对REMA DEM高程精度评估的影响。该文精度验证的结果能够为后续利用该数据产品在平坦地区进行冰面湖水深反演等工作提供理论依据。
Antarctic Digital Elevation Models(DEMs)provide critical topographic support for polar scientific expeditions and enable the estimation of melt pond volumes.However,conventional ground calibration methods face implementation challenges in extreme Antarctic environments.Spaceborne Light Detection And Ranging(LiDAR)effectively addresses this limitation by directly acquiring high-precision surface elevation data.ICESat-2,a next-generation laser altimetry satellite,features an exceptionally small laser footprint spacing of merely 0.7 m.The elevation data products of ICESat-2 over the Antarctic ice sheet achieve centimeter-level accuracy using the Reference Elevation Model of Antarctica(REMA)source data.This study first validated the elevation accuracy of the ICESat-2 ATL06(Advanced Topographic Laser Altimeter System Land Ice Height)data products using the IDHDT4(IceBridge HiCARS Depth Digitizer Time Series,Version 4)data from the 2015 Operation IceBridge campaign of NASA in the McMurdo Dry Valleys region and mitigated disturbances from cloud cover,snowfall,and other factors through a quality control algorithm.Building upon this validation,this study systematically assessed the elevation accuracy of the 32 m resolution REMA DEM across selected low-ablation regions of the Antarctic ice sheet,delineated according to Antarctic drainage basin boundaries,using the ATL06 data as a reference.Results showed that REMA DEM achieves submeter accuracy(comparable to laser altimetry precision)in flat terrains with slopes below 5°,with a Root-Mean-Square Error(RMSE)of 0.72 m and a Mean Absolute Error(MAE)of 0.31 m.For moderate slopes of 5°-10°,the RMSE and MAE increased to 1.91 and 1.06 m,respectively;meanwhile,slopes of 10°-15°yielded values of 2.30 m(RMSE)and 1.57 m(MAE).Even at steeper slopes of 30°,the elevation error remained controlled,with the RMSE not exceeding 3.5 m.This study further quantified the impact of ground track orientation relative to slope aspect and seasonal variations.Track-aspect angles perpendicular to slopes intensify errors(e.g.,RMSE increases by 170%at a slope of 15°),whereas seasonal differences in elevation errors remain minimal(i.e.,<5%).The validation framework demonstrates the robustness of REMA DEM across diverse Antarctic terrains,providing a theoretical foundation for different applications,such as lake ice surface bathymetry inversion.
作者
王杰
张智宇
姜洋
赵朴凡
吴松华
WANG Jie;ZHANG Zhiyu;JIANG Yang;ZHAO Pufan;WU Songhua(College of Marine Technology,Faculty of Information Science and Engineering,Ocean University of China,Qingdao 266100,China;China Academy of Space Technology,Beijing 100094,China;Satellite Navigation and Positioning Technology Research Center,Wuhan University,Wuhan 430072,China;Laoshan National Laboratory,Qingdao 266237,China)
出处
《雷达学报(中英文)》
北大核心
2025年第3期576-588,共13页
Journal of Radars
基金
国家自然科学基金(42206181,U2106210)
山东省自然科学基金(ZR2022QD125)
中国博士后基金(2021TQ0313)。
关键词
星载光子计数激光雷达
数字高程模型
高程精度评估
激光测高
南极DEM
Space-borne photon-counting LiDAR
Digital Elevation Model(DEM)
Elevation accuracy assessment
Laser altimetry
Antarctica DEM
作者简介
王杰,硕士,主要研究方向为星载激光雷达几何定位;通信作者:张智宇,博士,讲师,主要研究方向为激光遥感与光电检测。zhangzhiyu@ouc.edu.cn;姜洋,硕士,高级工程师,主要研究方向为卫星总体设计;赵朴凡,博士,主要研究方向为星载激光测高仪误差理论、标定方法、数据处理以及测绘应用;吴松华,博士,教授,主要研究方向为大气海洋激光探测技术与应用。
