联合CryoSat-2测高数据和地面高程数据建立东南极拉斯曼丘陵地区DEM

DEM Production for Larsemann Hills Combining Cryosat-2 and Ground-based Elevation Data

拉斯曼丘陵地区位于东南极伊丽莎白公主地,中国南极中山站位于拉斯曼丘陵的东部,是中国南极科学考察的重要地区。数字高程模型(DEM)是南极冰盖变化研究的基础,卫星测高数据是南极地区构建DEM的主要数据来源。CryoSat-2是新一代用于极地冰盖和海冰监测的测高卫星,联合2013年和2014年南极冬季的CryoSat-2测高数据以及中国、澳大利亚、印度三个国家现场测量的60余个地面高程数据,利用克里金插值方法建立了拉斯曼丘陵地区200 m分辨率的DEM(简称LA-DEM)。利用未参与插值的地面高程数据对新建立的LA-DEM进行了验证,并与Bamber 1km DEM、ICESat DEM、RAMPv2 DEM以及BEDMAP 2等四种国际上常用的南极DEM进行比较,结果表明LA-DEM的高程精度约为19.7 m,优于其他4种南极DEM。

Larsemann Hills,located on the Ingrid Christensen Coast of Princess Elizabeth Land in East Antarctica,is an ideal area for Antarctic ice sheet and oceanographic studies.Digital elevation models are of importance to many geoscientific and environmental studies in Antarctic and due to relatively poor coverage by ground based surveys,the main data source for developing Antarctic DEMs is satellite altimetry.The new operating satellite-borne altimeter for ice applications is the ESA satellite CryoSat-2,launched in April 2010.Based on CryoSat-2 data collected during austral winter of 2013 and 2014 and ground based elevation points from China,India,and Australia,a new 200 m DEM for the Larsemann Hills,termed LA-DEM,was derived by the Ordinary Kriging method.The accuracy of LA-DEM was assessed by residual elevation points.The results show that the accuracy of LA-DEM is about 19.7 m,andbetter than four commonly used Antarctic DEMs.