摘要
南极冰盖数字高程模型(digital elevation model,DEM)对南极环境变化和地形研究具有重要作用,利用GPS实测数据和卫星测高数据建立DEM是构建南极冰盖表面DEM的重要方法。考虑到实测GPS数据的精度较高,而卫星测高的空间分辨率占优,本文探讨综合利用这两种数据构建南极Dome A区域DEM。法国国家空间研究中心和印度空间研究组织共同研制的SARAL卫星是Envisat的后续卫星,搭载的Alti Ka雷达高度计首次采用了Ka波段,可以极大减小电离层的影响,提高测距精度和卫星数据的空间分辨率。本文首先利用中国南极第29次科学考察在Dome A区域的实测GPS数据对SARAL数据进行精度评定,然后利用实测GPS数据对SARAL测高数据进行高程修正,联合GPS数据获取得到了Dome A区域300 m分辨率的DEM。结果表明SARAL的高程精度为0.615 m,而联合GPS数据能改善DEM精度,提高到0.261 m。
DEM of the Antarctic ice sheet plays an important role on the Antarctic environment change and the topographic study. GPS data and satellite altimetry data are two common data to construct DEM of the Antarctic ice sheet. Considering the accuracy of GPS measurement data and the spatial resolution of satellite altimetry, this paper obtains a new DEM over Dome A using SARAL and GPS data. SARAL satellite is a follow-on satellite of Envisat, which is jointly developed by Centre National d＇Etudes Spatiales （CNES） and Indian Space Research Organization （ISRO）. A new radar altimeter AltiKa with the Ka band was first used to reduce the influence of the ionosphere and to improve spatial resolution. The GPS data collected in 29th CHINARE Expedition over Dome A were used to evaluate the accuracy of the DEM using SARAL data. Then a new DEM used obtained by the combination of SARAL data and GPS data over Dome A. The results show that the height accuracy of the SARAL data is about 0.615 m. Moreover, it can reduce to 0.261 m after the combination between GPS data and SARAL data.
出处
《极地研究》
CAS
CSCD
2017年第2期204-209,共6页
Chinese Journal of Polar Research
基金
全球变化研究国家重大科学研究计划(973计划)(2013CBA01804)
国家自然基金(41476163
41106163)
南北极环境综合考察及资源潜力评估专项(CHINARE2016)
测绘地理信息公益性行业科研专项经费项目(201412009)资助
关键词
SARAL
数字高程模型
精度评估
数据融合
SARAL, digital elevation model （DEM）, accuracy evaluation, data fusion
