Description
Summary:The metadata record at the end of the report outlining the development of the bathymetric grid of the region 60E to 90E and 55S to 70S includes details about Lineage, Positional Accuracy, Attribute Accuracy, Logical Consistency and Completeness. The merging of this grid with the grid to the north was done in ArcGIS 9.2 using the Mosaic tool in ArcToolbox (Data Management Tools - Raster - Mosaic) with the 'Blend' method. Contours (100 metre interval) were derived from the final grid in ArcGIS 9.2 using the following procedure: 1) The final grid was smoothed using the Focal Statistics tool in ArcToolbox (Spatial Analyst Tools - Neighbourhood - Focal Statistics) with a mean value over a 3x3 rectangular window. 2) Contours were generated from the smoothed grid using the Spatial Analyst extension. 3) The contours were generalised using the GENERALIZE command in ArcInfo workstation using the bendsimplify option with a weed tolerance of 0.01 degrees. 4) The generalised contours were smoothed using the SPLINE command in Arcedit with a grain distance of 0.002 degrees. Steps 3 and 4 were carried out at the Australian Antarctic Data Centre. This dataset is a bathymetric grid of the region 60E to 90E and 48.45S to 70S, created in a geographic coordinate system based on a WGS84 horizontal datum. The grid has a cell size of 0.005 degrees. Most of the work involved creating a bathymetric grid of the region 60E to 90E and 55S to 70S which was generated from the latest available multibeam swath bathymetry, fisheries' surveys and satellite altimetry data. A report outlining the development of this grid is available for download (see the related url below). This grid was then merged with the bathymetric grid described by the metadata record 'Bathymetric Grid of Heard Island - Kerguelen Plateau Region (2005)', which covers the region 68E to 80E and 48S to 56S. Hence the final grid has two 'No data' areas between 48.45S to 55S: 60E to 68E and 80E to 90E. The final grid is available for download as a geotiff and ArcInfo ascii file and contours derived from the grid are available for download as a shapefile (see the related urls below).