AUSGeoid98 v.1.0 data files: (sf49-11)

AUSGeoid98 data files contain a 2 minute grid of AUSGeoid98 data covering the Australian region, which you can use to interpolate geoid-ellipsoid separations for the positions required.You can use your own interpolation software, or you can use Geoscience Australia's Windows Interpolation software (Winter). The data files are text files in a standard format that cover the same area as standard topographic map areas. Files covering both 1:250,000 (approximately 100 x 150 km) and 1:1,000,000 (approximately 400 x 600 km) map areas are available. There is a 4 minute overlap on all sides of each area. Data format: AUSGeoid98 data files have a header record at the start of each file, to distinguish them from the superseded AUSGeoid93 data files. AUSGeoid98 data files show the geoid-ellipsoid separation to 3 decimal places, while the superseded AUSGeoid93 data files showed only 2 decimal places. AUSGeoid98 deflections of the vertical were computed from the geoid-ellipsoid separation surface, while the AUSGeoid93 deflections of the vertical were computed from OSU91A.

澳大利亚大地水准面模型98（AUSGeoid98）数据文件包含覆盖澳大利亚区域的2分钟分辨率网格数据，可用于对所需点位插值计算大地水准面与椭球面的偏差（大地水准面差距）。用户可选用自研插值软件，亦可使用澳大利亚地球科学局（Geoscience Australia）开发的Windows版插值工具Winter。当前提供采用标准格式的文本数据文件，其覆盖范围与标准地形图图幅一致，涵盖1:250,000（约100×150千米）及1:1,000,000（约400×600千米）两种比例尺的地形图图幅。所有图幅的各边界均设有4分钟的重叠区域。数据格式说明：每个澳大利亚大地水准面模型98（AUSGeoid98）数据文件的起始位置均包含头部记录，用于与已被取代的AUSGeoid93数据文件进行区分。澳大利亚大地水准面模型98的数据可将大地水准面与椭球面的偏差精确至小数点后三位，而已被取代的AUSGeoid93数据仅能精确至小数点后两位。澳大利亚大地水准面模型98的垂线偏差基于大地水准面差距表面计算得到，而AUSGeoid93的垂线偏差则基于OSU91A模型计算得出。