# au_ga_README.txt The files in this section result from the conversion of datasets originating from [Geoscience Australia](http://www.ga.gov.au) ### Australia: AUSGeoid98: GDA94 -> AHD height *Source*: [Geoscience Australia](http://www.ga.gov.au/ausgeoid/comp.html) *Format*: GeoTIFF converted from GTX *License*: [Creative Commons Attribution 4.0] *Converter*: gdal_translate -of GTX AUSGeoid98.gsb AUSGeoid98.gtx -b 1 * au_ga_AUSGeoid98.tif ### Australia: AUSGeoid09: GDA94 -> AHD height *Source*: [Geoscience Australia](http://www.ga.gov.au/ausgeoid/comp.html) *Format*: GeoTIFF converted from GTX *License*: [Creative Commons Attribution 4.0] *Converter*: gdal_translate -of GTX AUSGeoid09_V1.01.gsb AUSGeoid09_V1.01.gtx -b 1 Uses AusGeoid09 model which uses bi-cubic interpolation; bi-linear interpolation of the grid file will give results agreeing to within 1cm 99.97% of the time. * au_ga_AUSGeoid09_V1.01.tif ### Australia: AUSGeoid2020: GDA2020 -> AHD height *Source*: [Geoscience Australia](http://www.ga.gov.au/ausgeoid/comp.html) *Format*: GeoTIFF converted from GTX *License*: [Creative Commons Attribution 4.0] *Converter*: gdal_translate AUSGeoid2020_20180201.gsb tmp.tif -a_nodata -999 -b 1 && gdalwarp tmp.tif AUSGeoid2020_20180201.gtx -dstnodata -88.8888015747070312 -of GTX Uses AusGeoid2020 model. * au_ga_AUSGeoid2020_20180201.tif ### Australia: AGQG (version 20191107): GDA2020 -> AVWS height *Removed*: in PROJ-data v1.7 (use v1.6 to get it). Superseded by au_ga_AGQG_20201120.tif *Source*: [Geoscience Australia](https://www.icsm.gov.au/sites/default/files/2020-08/AVWS%20Technical%20Implementation%20Plan_V1.2.pdf) *Format*: GeoTIFF converted from source GeoTIFF *License*: [Creative Commons Attribution 4.0] * au_ga_AGQG_20191107.tif ### Australia: AGQG (version 20201120): GDA2020 -> AVWS height *Source*: [Geoscience Australia](https://icsm.gov.au/sites/default/files/2020-12/AVWS%20Technical%20Implementation%20Plan_V1.3_0.pdf) *Format*: GeoTIFF converted from source GeoTIFF *License*: [Creative Commons Attribution 4.0] * au_ga_AGQG_20201120.tif [Creative Commons Attribution 4.0]: https://creativecommons.org/licenses/by/4.0/