AUSGeoid98 v.1.0 data files: (sd51-01)

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 Data format: AUSGeoid98 data files have a header record at the start of each file, to distinguish them from the superseded AUSGeoid93 data files. AUSGeoid98 data files show the geoid-ellipsoid separation to 3 decimal places, while the superseded AUSGeoid93 data files showed only 2 decimal places.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分钟网格数据，可用于对所需位置的大地水准面-椭球面差距（geoid-ellipsoid separations）进行插值计算。您可以使用自行开发的插值软件，也可采用澳大利亚地球科学局（Geoscience Australia）的Windows插值软件Winter。这些数据文件为标准格式的文本文件，覆盖范围与标准地形图区域一致，包含1:250,000（约100×150公里）和1:1,000,000（约400×600公里）两种比例尺的地图区域，且每个区域四周存在4分钟的重叠。数据格式上，每个文件开头设有头记录，以区分已被取代的AUSGeoid93数据文件；AUSGeoid98数据将大地水准面-椭球面差距精确至小数点后三位，而AUSGeoid93仅保留至两位。此外，AUSGeoid98的垂直偏差由大地水准面-椭球面差距表面计算得出，AUSGeoid93的垂直偏差则基于OSU91A计算。