AUSGeoid98 v.1.0 data files: (sd54-06)

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 Data format: AUSGeoid98 data files have a header record at the start of each file, to distinguish them from the superseded AUSGeoid93 data files. AUSGeoid98 data files show the geoid-ellipsoid separation to 3 decimal places, while the superseded AUSGeoid93 data files showed only 2 decimal places.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.

AUSGeoid98数据文件包含覆盖澳大利亚区域的2分分辨率格网数据集，可针对所需点位的大地水准面-椭球面分离值（geoid-ellipsoid separations）开展插值计算。用户既可使用自研插值软件，也可选用澳大利亚地质科学局（Geoscience Australia）推出的Windows版插值工具Winter。该类数据文件为标准格式文本文件，其覆盖范围与标准地形图图幅一致，涵盖1:250000（约100×150千米）与1:1000000（约400×600千米）两种比例尺的图幅数据。所有图幅的四周均设置有4分的重叠区域。数据格式说明：AUSGeoid98数据文件的每个文件起始处均带有头部记录，用于与已废止的AUSGeoid93数据文件相区分。AUSGeoid98数据文件将大地水准面-椭球面分离值精度保留至小数点后三位，而已废止的AUSGeoid93数据文件仅保留两位小数。AUSGeoid98的垂线偏差基于大地水准面-椭球面分离曲面计算得到，而AUSGeoid93的垂线偏差则以OSU91A模型为计算依据。