A database containing sounding data around Macquarie Island. Track line data for each data source is included.

The soundings were digitized from bathymetric chart: Bathymetry of Lutzow-Holm Bukta (Lutzow-Holm Bay) by the Japanese, National Institute of Polar Research (NIPR) from Special Map Series of National Institute of Polar Research No. 4b, 2002 - map number 12852 in the SCAR map catalogue. These data have been created by the Japanese, but as such no metadata record for the data exists in the Japanese portal of the Antarctic Master Directory. Australian users of these data should use this metadata record (providing credit to the Japanese), until a Japanese version has been created.

This dataset consists of underway data, including bathymetric data, collected aboard Australian Antarctic Division research vessels between 1985 and 2012. The data are available in csv format and the raw SIMRAD format. In the csv files bathymetric data is in the WTR_DEPTH_M column. Some voyages will not have bathymetric data associated with them. The csv data may have been quality checked. Most of the underway data was quality checked ('dot zapped') up to and including voyage 4 2003/04. Data quality reports are available by searching at http://data.aad.gov.au/aadc/voyages/ Other than on Marine Science voyages, the Aurora Australis bathymetric data gathering procedures prior to about 2000 were not checked during the voyage. The echo sounder was turned on in Hobart and if it stopped working during the voyage, then there was no one to get it going again. Bathymetric data from these voyages that has been processed by the Royal Australian Navy is available via other metadata records linked to the parent record with ID AAD_voyage_soundings.

A high resolution bathymetric grid of the nearshore area at Casey station, Antarctica was produced by Geoscience Australia by combining data from two multibeam hydrographic surveys: 1) A survey conducted by the Royal Australian Navy in 2013/14. Refer to the metadata record 'Hydrographic survey HI545 by the RAN Australian Hydrographic Service at Casey, December 2013 to January 2014' with ID HI545_hydrographic_survey. 2) A survey conducted by Geoscience Australia and the Royal Australian Navy in 2014/15. Refer to the metadata record 'Hydrographic survey HI560 by the RAN Australian Hydrographic Service at Casey, December 2014 to February 2015' with ID HI560_hydrographic_survey and the metadata record 'Seafloor Mapping Survey, Windmill Islands and Casey region, Antarctica, December 2014 - February 2015' with ID AAS_3326_seafloor_mapping_casey_2014_15. The grid has a cell size of one metre and is stored in a UTM Zone 49S projection, based on WGS84. Further information is available from the Geoscience Australia website (see a Related URL).

A polygonised bathymetric dataset covering the Southern Ocean. The dataset was compiled from data sourced from the General Bathymetric Chart of the Oceans (GEBCO) Digital Atlas, 2003 edition, and the Antarctic Digital Database, version 4.

This metadata record is a modified child record of an original parent record originating from custodians of data associated with Geoscience Australia (The identifier of the parent record is ANZCW0703009248, and can be found on the Australian Spatial Data Directory website - see the URL given below). Taken from the report: A bathymetric grid of the Heard Island-Kerguelen Plateau Region (Longitudes 68 degrees E - 80 degrees E, Latitudes 48 degrees S - 56 degrees S) is produced. In doing so, the individual datasets used have been closely examined and any deficiencies noted for further follow up or have been rectified immediately and the changes documented. These datasets include modern multibeam data, coastline data obtained from the World Vector Shoreline, echosounder data from research, fishing and Customs vessels and satellite derived bathymetric data. A hierarchical system was employed whereby the best and most extensive datasets were gridded first and applied as a mask to the next best dataset. A new masking grid would be formed from these datasets to pass non-overlapping data in the next best dataset. This procedure was employed until finally the satellite data were masked. All the various levels of masked data were then brought together by the gridding algorithm (Intrepid - Desmond Fitzgerald Associates) and an ERMapper format grid produced. A grid cell size of 0.005 degrees (nominal 500m) was used with many iterations of minimum curvature gridding and several passes of smoothing. The final grid is available in ERMapper, ArcInfo and ASCII xyz formats.

This metadata record is a modified child record of an original parent record originating from custodians of data associated with Geoscience Australia (The identifier of the parent record is ANZCW0703006701, and can be found on the Australian Spatial Data Directory website - see the URL given below). A bathymetric grid of the Macquarie Island Region (Longitudes 151 E and 167 E, Latitudes 48 S and 62 S) was produced. In doing so, the individual datasets used were closely examined and any deficiencies noted for further follow up or were rectified immediately and the changes documented. These datasets include modern multibeam data, coastline data obtained from georeferenced SPOT imagery, hydrographic quality data, echosounder data from research and fishing vessels and satellite derived bathymetric data. A hierarchical system was employed whereby the best and most extensive datasets were gridded first and applied as a mask to the next best dataset. A new masking grid would be formed from these datasets to pass non-overlapping data in the next best dataset. This procedure was employed until finally the satellite data were masked. All the various levels of masked data were then brought together by the gridding algorithm (Intrepid and Desmond Fitzgerald Associates) and an ERMapper format grid produced. A grid cell size of 0.00225 (nominal 250m) was used with many iterations of minimum curvature gridding and several passes of smoothing. The final grid is available in geotiff, ArcInfo ascii and xyz text formats. A detailed report of the work completed is also available.

Pre-processed satellite imagery [Mawson Station_Preprocessed_WV2_Shallow Water.tif] IMPORTANT: This data cannot be shared due to licensing conditions and is provided for archival purposes only. Worldview-2 Imagery was provided at Processing level 2A in GCS WG84. The following Pre-processing steps were applied: Radiometric Correction: Digital Numbers converted to TOA Reflectance Atmospheric Correction: Dark Object Subtraction Masking: Masking of Land and Ice features using classification of accompanying PAN imagery Shallow Water Masking: Deep water masked out by thresh-holding the green and yellow bands The pre-processed data is provided as an 8-band Geotiff in wg84 with pixels of 0.000018° Satellite-derived bathymetry grid [Mawson Station_SDB_wg84_alat.tiff] This bathymetry dataset was produced by applying the SMART-SDB model to Worldview 2 Multispectral Image acquired on 20170129 at 05:21:13Z. Singlebeam bathymetry data acquired in February 20191 using a CEESCOPE 200kHz SBES with CMAX SSS, with vertical and horizontal accuracy of 0.50m and 3.00m respectively, was used for both calibration and validation of the SMART-SDB model. Derived data was smoothed using a low pass filter, and manually cleaned for erroneous returns (however some may still exist). A description of the methods is available in the attached reports. Projection: GCS WG84 Tidal datum: ALAT (approximate lowest astronomical tide) Format: geotiff, ASCI xyz Depths Derived from Satellite Imagery. For SA awareness only. Not for Navigation. Vertical Accuracy is un-assessable and should be considered worse than ZOC C. Undetected features significant to surface navigation may exist. Bathymetry map (Mawson Station SDB Chart_OFFICIAL.pdf) This map shows the hydrographic chart from Mawson Station overlayed with the new satellite-derived bathymetry data. Python Scripts and Guide These scripts were developed to automate extraction of satellite-derived bathymetry from the Worldview-2 imagery. Details of the scripts and how to apply them are outlined in the guide: Antarctica SDB Project How To.docx Final report [AASP4392_Antarctica SDB Project_FINAL_REPORT.docx] This report “Potential of Satellite-Derived Bathymetry mapping in Antarctica using high-resolution multispectral imagery” outlines the objectives, methods, results and conclusions for the satellite-derived bathymetry project (AASP4392). It has not been peer-reviewed. 1 An Australian Hydrographic Service survey acquired singlebeam bathymetry data using a CEESCOPE 200kHz SBES with CMAX SSS, with vertical and horizontal accuracy of 0.50m and 3.00m respectively, in the nearshore waters of Holmes Bay near Mawson station in February 2019. This survey is part of Australian Antarctic Project (AAP) 5093: Hydrographic Surveying and Seabed Characterisation (CI: Ursula Harris) The data was extracted from the Australian Hydrographic Office database (20190208 Hydrographic survey) and is available at: O'Brien, P.E. (2011) Coastal seabed mapping survey, Vestfold Hills, Antarctica, February-March 2010, Ver. 2, Australian Antarctic Data Centre https://data.aad.gov.au/metadata/records/Davis_multibeam_grids)

Bathymetric Contours and height range polygons of approaches to Casey Station, derived from RAN Fair sheet, Aurora Australis and GEBCO soundings.

This dataset contains temperature data obtained from XBTs (expendable bathythermographs) deployed by vessels during different cruises between Tahiti and Auckland (New Zealand). Expendable Bathythermographs (XBTs) have been used for many years by oceanographers to measure the temperature of the upper ocean. These instruments are simple devices which are designed to be deployed from moving vessels, enabling broad scale coverage of the world's oceans.