The AADC (Australian Antarctic Data Centre) is in the process of converting all internally held spatial datasets to the ITRF2000 horizontal datum. This consolidated dataset consists of surveys HI623_alatB_gg, HI625_alatB_GG, HI632_alat_B_gg, HI632_alat_C_gg, LADSII_MMI20756_HSDB_T0001_SD_100029052_op, LADSII_MMI20756_HSDB_T0001_SD_100029053_op, LADSII_MMI20756_HSDB_T0001_SD_100029054_op converted to ITRF2000 horizontal datum with Z conversion values for multiple height datums. The data was provided to the AAD by Paul Digney of Jacobs consulting in March 2021.
Included survey datasets:
• HI623_alatB_gg
• HI625_alatB_GG
• HI632_alat_B_gg
• HI632_alat_C_gg
• LADSII_MMI20756_HSDB_T0001_SD_100029052_op
• LADSII_MMI20756_HSDB_T0001_SD_100029053_op
• LADSII_MMI20756_HSDB_T0001_SD_100029054_op
All data are in horizontal datum ITRF2000 and have been combined into a single ESRI geodatabase feature class titled AHS_Surveys_Macca_ITRF2000.
Attribute data shows quality information, conversion factors (shift in metres) for multiple datums and the MSL orthometric height:
Column Name Alias Meaning
Easting Easting Easting ITRF2000
Northing Northing Northing ITRF2000
LAT_to_GRS LAT_to_GRS LAT (Chart Datum) to GSR80
LAT_to_Mac LAT_to_Mac LAT to Macca MSL
Z_To_GRS80 Z_To_GRS80 Height to the Ellipsoid
Z_To_Macca Z_To_Macca Local MSL orthometric height
Vertical_U Vertical_U How good is the Vertical Position
Horizontal Horizontal How good is the Horizontal Position
Uncertaint Uncertaint Uncertainty Comments
Depth_Comm Depth_Comments
Vertical uncertainty ranges from 0.5 to 1.2 m and horizontal uncertainty ranges from 2 to 5.5 m. Null values indicate unknown uncertainty.
See the attached document ‘Metadata_Record_Macqaurie Island Final.xlsx’ for further details.