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 It has not been peer-reviewed. 1 An Australian Hydrographic Service survey acquired singlebeam bathymetry data using a CEESCOPE 200kHz SBES with CMAX SSS, with vertical and horizontal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)

From February to March 2010, Geoscience Australia (GA) conducted a multibeam sonar survey of the coastal waters of the Vestfold Hills in the Australian Antarctic Territory. The survey was conducted jointly with Australian Antarctic Division (AAD) and the Deployable Geospatial Survey Team (DGST) of the Royal Australian Navy. The survey was aimed primarily at understanding the character of the sea floor around Davis Station to better inform studies of the benthic biota and the possible impacts of the Davis sewage outfall. DGST were involved to ensure that the bathymetric data could be used to update and extend the nautical charts of the Davis area. The survey was conducted using GA's Kongsberg EM3002D multibeam echo sounder and C-Nav Differential GPS system mounted on the AAD work boat Howard Burton. Sixteen under water videos were also collected using the GA Raytech camera system and 3 grabs were also collected to compliment an intensive sampling program by AAD divers and a sampling program conducted in the 1990's by University of Tasmania (Franklin, 1996). An area of 42 km2 was surveyed intensively immediately off Davis and additional survey lines were run to Long Fjord in the north and to Crooked Fjord and the Sorsdal Glacier in the south. The main survey area had between 150% and 200% coverage as the seabed was esonified from opposing angles to resolve and provide detail to the numerous features of the seafloor such as rocky reefs, iceberg scours, boulders, anchor chain drag marks and grounded icebergs. The new high resolution data provided detailed maps of sea bed morphology and texture classification to complement sample data. Sixteen video transects were collected and 3 grab samples collected in water too deep for the Australian Antarctic Division Diving program. New high resolution bathymetric grids have been prepared for scientific use and further processing for hydrographic charting is ongoing. A new sea floor geomorphic map has been prepared using the multibeam data, preliminary video and sampling data. The project was a component of Australian Antarctic Science (AAS) Project 2201 - Natural Variability and Human Induced Change on Antarctic Nearshore Marine Benthic Communities. In 2011, Dr Phil O'Brien provided to the Australian Antarctic Data Centre the following interim data: 75 cm multibeam data in CARIS format; and a 4 metre resolution bathymetric grid and an image of the sea floor, both derived from the 75 cm multibeam data. This data was made available for download from this metadata record. In August 2013, Geoscience Australia released 2 metre resolution bathymetric and backscatter grids after further processing of the multibeam data. The bathymetry and backscatter data have now been fully processed checked and validated by Geoscience Australia and supersede the interim data. The interim data has been archived by the Australian Antarctic Data Centre. The 2 metre resolution grids and final report are available for download from the Geoscience Australia website.

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).

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.

This terrestrial dataset was collected at Ursula Harris’s behest by Craig Hamilton and a Naval Survey team on 09 January 2018 when sea conditions prevented the team from taking bathymetric measurements. This survey was intended to fill gaps in the existing Mawson Station survey data and includes 29 previously unrecorded features comprised of bollards, HF towers, flagpoles, masts, antennae, ionosonde transmitter and receiver, the Mawson Signpost and the Douglas Mawson Bust.

The Davis Coastal Seabed Mapping Survey, Antarctica (GA-4301 / AAS2201 / HI468) was conducted on the Australian Antarctic Division workboat Howard Burton during February-March 2010 as a component of Australian Antarctic Science (AAS) Project 2201 - Natural Variability and Human Induced Change on Antarctic Nearshore Marine Benthic Communities. The survey was undertaken as a collaboration between Geoscience Australia, the Australian Antarctic Division and the Australian Hydrographic Service (Royal Australian Navy). The survey acquired multibeam bathymetry and backscatter datasets from the nearshore region of the Vestfold Hills around Davis Station, Antarctica. These datasets are described by the metadata record with ID Davis_multibeam_grids. This dataset comprises an interpreted geomorphic map produced for the central survey area using multibeam bathymetry and backscatter grids and their derivatives (e.g. slope, contours). Six geomorphic units; basin, valley, embayment, pediment, bedrock outcrop and scarp were identified and mapped using definitions suitable for interpretation at the local scale (nominally 1:10 000). Polygons were created using a combination of automatic extraction and manual digitisation in ArcGIS. For further information on the geomorphic mapping methods and a description of each unit, please refer to OBrien P.E., Smith J., Stark J.S., Johnstone G., Riddle M., Franklin D. (2015) Submarine geomorphology and sea floor processes along the coast of Vestfold Hills, East Antarctica, from multibeam bathymetry and video data. Antarctic Science 27:566-586. This metadata record was created using information in Geoscience Australia's metadata record at http://www.ga.gov.au/metadata-gateway/metadata/record/89984/

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.

This GIS dataset is the result of the interpolation of bathymetry from depth measurements made in Long and Tryne Fjords in the Vestfold Hills, Antarctica (see Entry: VH_bathy_99). The Topogrid command within the ArcInfo GIS software, version 8.0.2, was used to do the interpolation. Coastline and spot height (heights above sea level) data, extracted from the Australian Antarctic Data Centre's Vestfold Hills topographic GIS dataset (see Entry: vest_hills_gis), was also used as input data to optimise the interpolation close to the coastline. See related URLs for a map showing the interpolated bathymetry.

Geoscience Australia, the Royal Australian Navy (RAN) and the Australian Antarctic Division (AAD) conducted a hydrographic and seafloor characterisation survey in nearshore waters offshore from Davis Station in the Australian Antarctic Territory. Multibeam bathymetry data was acquired during January-February 2017 and a high-resolution (2 m) bathymetry grid produced for the survey area.

Water depth measurements were taken in Long Fjord during early winter in 2007. The measurements were collected by Graham Cook, station leader at Davis Station in the Australian Antarctic Territory. The measurements were made by dropping a weighted line off the back of a quad bike, after drilling a hole through the sea ice. Measurements were made approximately every 100 metres. The download file contains a csv spreadsheet which lists each waypoint, plus the corresponding water depth and any comments. The text file contains the waypoint information collected by the Garmin GPS unit. Data in the text file are comma separated and are interpreted as follows: WP,D,001 (waypoint) , -68.51341000, 78.06903000,(Latitude and Longitude) 05/25/2007, 10:25:35, (Date and time Downloaded to Computer) 24-MAY-07 11:40:42 (Date and time of reading). Time is in local time. Vegetation was found on the weight that we used when we first started at the seaward end of the Fjord and then again in shallow water between Brookes Hut and a small island 800 or 900 metres out from Brookes. The weight is quite smooth and does not pick up a lot. The reference given below provides some further information about previously collected bathymetry data in Long Fjord. Furthermore, also see the metadata records: 'Bathymetric data of Long and Tryne Fjords at Vestfold Hills, Antarctica, collected in December 1999 [VH_bathy_99]' 'Interpolated bathymetry of Long and Tryne Fjords, Vestfold Hills, Antarctica [long_tryne_bathy]' The fields in this dataset are: Waypoint Latitude Longitude Water Depth Date Time