Geostatistical estimation from radar altimeter data with respect to morphological units outlined by SAR data: application to Lambert Glacier/Amery Ice Shelf, East Antarctica
Geostatistical estimation from radar altimeter data with respect to morphological units outlined by SAR data: application to Lambert Glacier/Amery Ice Shelf, East Antarctica
复制标题
根据雷达高度计数据对 SAR 数据概述的形态单元进行地统计估计：应用于南极洲东部兰伯特冰川/阿默里冰架
作者：
R. Stosius;U. Herzfeld
摘要本文的目的是比较两种克立格方法，普通克立格和层内克立格，计算数字高程模型（DEM）的雷达高度计数据，并应用于兰伯特冰川/埃默里冰架系统，东南极洲。两个新的DEM。首先，兰伯特冰川/埃默里冰架系统的DEM计算从1997年欧洲遥感卫星-2（ERS-2）雷达高度计（RA）数据使用地统计插值。RA数据具有高的沿轨道密度，但轨道之间的间隙为几公里，这取决于观测模式;这需要插值。由于冰流/冰架系统是冰川学调查的主要兴趣，在第一种方法中使用的兰伯特冰川冰表面的变差函数特性。由此产生的地图对冰川和冰架的误差很小。为了匹配构成Lambert Glacier/Amery Ice Shelf区域的不同形态单元的表面特征，第二个DEM构建如下：我们利用1997年第一次南极成像活动期间收集的RADARSAT合成孔径雷达（SAR）数据，并由Jezek（1999）组成125米后向散射数据镶嵌图，我们共同参考125米的镶嵌与测高派生DEM。兰伯特冰川/埃默里冰架地区，然后细分为几个区域，这些区域是同质的SAR镶嵌中确定的特征表面形态属性。对于这些地区，一个面向问题的复杂克里金法称为克里金地层内进行，并将由此产生的DEM是来自克里金法没有区域细分的DEM进行比较。
Abstract The objective of this paper is the comparison of two kriging methods, ordinary kriging and kriging within strata, for calculation of digital elevation models (DEMs) from radar altimeter data, and application to the Lambert Glacier/Amery Ice Shelf system, East Antarctica. Two new DEMs are presented. First, a DEM of the Lambert Glacier/Amery Ice Shelf system is calculated from 1997 European Remote-sensing Satellite-2 (ERS-2) radar altimeter (RA) data using geostatistical interpolation. RA data have high along-track density, but gaps between tracks are several kilometers, depending on the observation mode; this requires interpolation. Because the ice-stream/ice-shelf system is of primary interest in glaciological investigations, in the first approach a variogram characteristic of the Lambert Glacier ice surface is used. The resultant map has low errors for the glacier and the ice shelf. To match the surface characteristics of different morphological units that constitute the Lambert Glacier/Amery Ice Shelf region, a second DEM is constructed as follows: We utilize RADARSAT synthetic aperture radar (SAR) data that were collected in 1997 during the first Antarctic Imaging Campaign and composed into a 125m backscatter-data mosaic by Jezek (1999) and we co-reference the 125m mosaic with the altimetry-derived DEM. The Lambert Glacier/Amery Ice Shelf area is then subdivided into several regions which are homogeneous with respect to characteristic surface-morphological properties identified in the SAR mosaic. For those regions, a problem-oriented complex kriging method known as kriging within strata is performed, and the resulting DEM is compared to the DEM that was derived from kriging without regional subdivision.