All scientific data collected by the Australian Antarctic program (AAp) are eventually described in the Catalogue of Australian Antarctic and Subantarctic Metadata (CAASM). CAASM can be used to search through AAp data descriptions, and it also provides links to access publicly available datasets, which can either be immediately downloaded or obtained from the Australian Antarctic Data Centre (AADC).
Bathymetric Contours and height range polygons of approaches to Davis Station, derived from RAN Fair sheet, Aurora Australis and GEBCO soundings.
All the soundings from three RAN fair Sheets were digitised as points using Microstation. The fair sheets used were Approaches to Davis - Sheets
HI 171 V5/519-6877/9Scale 1:5 000
HI 120 V5/463-6877/1Scale 1:10 000
HI 120 SUP 1 V5/480-6877/7 Scale 1:10 000
Centre of gravity of the text was regarded as point position.
The points from each sheet were assigned the relevant Data Quality Indicator and merged into a single dataset. The data were then converted to ArcInfo format and merged with GEBCO 97 data and Aurora Australis data supplied by the Australian Antarctic Data Centre. DQI Regions and contours were generated from the resulting merged data set.
Contouring was performed using Intergraph's Siteworks. The contour interval was 5 metres in areas of scale 1:10 000, 2 metres in areas of 1:5000 scale and 50-200 metres in areas of much smaller scale (GEBCO and Aurora Australis). Resulting contour lines were converted to ArcInfo format and checked for overlapping lines. These were fixed where they occurred. The ends of the contours were closed using connectors and the resulting data set was built for polygons. The contour height values were transferred to the polygon tables. Depressions were determined by isolating closed polygons (without connectors); if these contained contours which went below the height range of the surrounding contours then they were tagged as depressions. Feature values for polygons were also determined from their surrounding lines.
The final data set was subdivided into Data Quality Indicator (DQI) regions so that the polygons and arcs could be tagged with the correct DQI value. DQI regions were assigned using the bounds of the most accurate data set first and then working out to the least accurate data set.
Stored data format: Shapefile
Available format type: Shapefile. Stored as geographicals with a projection file.
Access constraint: Data are available on the web. Conditions apply.
This data set conforms to the CCBY Attribution License
(http://creativecommons.org/licenses/by/4.0/).
Please follow instructions listed in the citation reference provided at http://data.aad.gov.au/aadc/metadata/citation.cfm?entry_id=davisbathy_gis when using these data.