基于GIS的中山站至Dome A冰盖考察数据处理和信息提取

GIS-BASED DATA PROCESS AND ANALYSIS ALONG THE GLACIOLOGICAL TRAVERSE ROUTE FROM ZHONGSHAN STATION TO DOME A

中山站至DomeA冰川学考察断面是国际ITASE计划的核心断面之一。首次利用GIS开展了该断面的数据处理与信息提取 ,采样点的布设与管理。介绍了ADD数字地图拼接与裁剪 ,野外数据和BEDMAP数据地理坐标投影变换的方法。利用ArcView内插等高线方法对GPS导航仪高程数据进行了校正。沿考察路线提取了BEDMAP的冰下基岩高程和冰厚度数据 ,以及冰盖表面的坡度与坡向数据。指出应进一步开展该断面以及兰伯特冰川盆地GIS应用研究。

The glaciological traverse route from Zhongshan Station to Dome A is one of the key routes in ITASE project. A preliminary application of GIS for the traverse route has been conducted to display, process, manage and analyze the data obtained by the 3rd Chinese Antarctic Inland Expedition. In this paper, the data sources for our GIS application research include the field data, such as 23 high-resolution GPS data and more than 600 GPS navigator data collected along the 1100 km traverse rate from Zhongshan Station to Dome A by the Chinese Inland Expedition; the surface, sub-ice topographic and ice thickness database provided by Antarctic digital database (ADD) and BEDMAP Project via World Wide Web. The tiling scheme of IMW 1:1 million scale map is adopted for ADD original scale and 1:1 million scale. The data within each IMW sheet boundary are subdivided into feature layers. Therefore, tiles should be first merged according to different features, such as cliff, coast, contour, elevation and so on, then you can clip the region you need using ArcView. In addition, BEDMAP data and field data should be firstly conducted projection transformation before adding them to ADD since ADD uses the Polar Stereographic projection. The major conclusions are achieved as fellows: 1. The route feature is created from GPS navigator data using Arc/Info. Then features defined by measurements along the route can be added to a map. 2. ADD have higher resolution along the route from Zhongshan Station to Dome A by comparing the high-resolution GPS data with the revised GPS navigator data via ADD and ArcView. GPS navigator data can be revised using ADD to promote the resolution. 3. The BEDMAP data along the traverse route is an important reference to our research on ice thickness sounding. The spatial distribution of BEDMAP data can be shown clearly after adding to ADD. 4. The triangulated irregulated network (TIN) of a region including Lambert Glacier Basin is created from the surface topography using 3D Analyst module and Spatial Analyst Module. Then the aspect (slope direction) and slope data along the traverse route can be derived from TIN. 5. It is a convenient and useful tool for us to record, query and display a variety of data in detail along the traverse when we travel inland.