Satellite-derived bathymetry – Mawson station, Holme Bay, 2017

Full description

1. 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:
1.    Radiometric Correction: Digital Numbers converted to TOA Reflectance
2.    Atmospheric Correction: Dark Object Subtraction
3.    Masking: Masking of Land and Ice features using classification of accompanying PAN imagery
4.    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°

2. 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.

3. 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.

4. 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

5. 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)

Lineage

Progress Code: completed

Statement: Significant banding and spectral variability was encountered in the source Worldview-2 Imagery. The accuracies calculated from the validation dataset are likely to decrease in areas further away from the location of the calibration data.