AUSGeoid98 v.1.0 data files: (sb52-16)

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 Data format: AUSGeoid98 data files have a header record at the start of each file, to distinguish them from the superseded AUSGeoid93 data files. AUSGeoid98 data files show the geoid-ellipsoid separation to 3 decimal places, while the superseded AUSGeoid93 data files showed only 2 decimal places.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（AUSGeoid98）数据文件包含覆盖澳大利亚区域的2分钟格网数据集，可用于对指定点位的大地水准面-椭球面差距（geoid-ellipsoid separations）进行插值计算。用户可选用自研插值软件，亦可使用澳大利亚地质科学局（Geoscience Australia）推出的Windows版插值工具Winter。 该数据文件均为符合标准格式的文本文件，覆盖范围与标准地形图图幅保持一致。当前可获取比例尺为1:250000（约100×150千米）及1:1000000（约400×600千米）的两类图幅数据，所有图幅的四周均设有4分钟的重叠区域。 数据格式说明如下：每个AUSGeoid98数据文件的起始位置均带有头记录，用于与已废止的AUSGeoid93数据文件进行区分。AUSGeoid98数据将大地水准面-椭球面差距保留至小数点后三位，而已废止的AUSGeoid93数据仅保留两位小数。AUSGeoid98的垂线偏差（deflections of the vertical）由大地水准面-椭球面分离曲面计算得到，而AUSGeoid93的垂线偏差则基于OSU91A模型计算得出。