Bathymetry of the 47 lakes on King George Island

The dataset contains information on the bathymetry of the 46 postglacial lakes located within the catchment area of Admiralty Bay (King George Island), as well as the Petrel Lake crater located on nearby Penguin Island. Fieldwork measurements were conducted in January and February 2025. The following weather conditions were recorded during the field works: air temperature: 0-5°C, wind speed: 0-5 m/s, cloudiness: 50-100% and there was no precipitation. Bathymetry measurements were taken with an Echo Sounder Deeper CHIRP+2, set to scan with a 16° beam at 240 kHz. The echo sounder was fixed to a small inflatable boat propelled by oars and connected by Bluetooth to a Nokia T21 tablet, which enabled the data to be saved. Depth was measured with an accuracy of 2.4 cm; depths shallower than 0.15 m were not recorded (https://support.deeper.eu/). The limitation of the measurements is the accuracy of the GPS on the tablet, which registers data with an accuracy of 1–10 metres depending on a clear sky and the number of satellites. Considering the positions of the points relative to each other, which were consistent with the route of the boat, most of them were registered correctly; only the whole lake may be shifted from its real position. Points registered in incorrect locations were deleted from the dataset (8.9% of all points). The approximate shoreline of the lakes was created based on field measurements using a Garmin Montana GPS, field observations, Sentinel-2 satellite images (resolution 5 m), facilitated by the Copernicus Data Space Ecosystem (https://browser.dataspace.copernicus.eu/) and satellite images available at Google Earth. On average, 23 depth measurements were taken per 100 m² of lake surface area. For very shallow lakes and lakes with a large surface area, there were fewer than 10 measurements per 100 m². Most lakes do not have an official name. In these cases, the names given in the database refer to the official name of a nearby geographical feature (e.g. a glacier, hill or nunatak) and are numbered if there is more than one lake.

The datasets consists of the three files: - KGI_lakes_bathymetry.csv: coordinates of each measured bathymetry point (latitude and longitude in the WGS-84 Antarctic Polar Stereographic georeferenced system), depth (in metres) and lake name. - KGI_lakes_information.csv: additional information about the lakes, including latitude and longitude of the lake's location, name, altitude (in metres above sea level), maximum depth (in metres), approximate time of creation, source of water supply and remarks from field observations. - KGI_lakes_shoreline.csv: coordinates of the approximate shoreline points of the lakes (latitude and longitude in the WGS-84 Antarctic Polar Stereographic georeferenced system, depth = 0.0 m). In case when there is no assigned depth = 0 m to shoreline point it means that a lake touches a glacier or a snowpack.

References to the sources of information about age of the lakes: - Battke Z. 1990. Admiralty Bay, King George Island, topographic map 1:50 000 scale. Państwowe Przedsiębiorstwo Wydawnictw Kartograficznych, Warszawa. - Pudełko R. 2002. Site of Special Scientific Interest No. 8 (SSSI 8), King George Island topographic map 1:12 500 scale, Department of Antarctic Biology, Polish Academy of Sciences. - Pudełko R., Angiel J.P., Potocki M., Jędrejek A., Kozak M. 2018. Fluctuation of Glacial Retreat Rates in the Eastern Part of Warszawa Icefield, King George Island, Antarctica, 1979-2018. Remote Sensing 10(6), 892; https://doi.org/10.3390/rs10060892 - Copernicus Data Space Ecosystem, https://browser.dataspace.copernicus.eu, access 24.07.2025 - Google Earth, access 24.07.2025 - Global Volcanism Program, 2025. [Database] Volcanoes of the World (v. 5.3.1; 6 Aug 2025). Distributed by Smithsonian Institution, compiled by Venzke, E. https://doi.org/10.5479/si.GVP.VOTW5-2025.5.3

The survey was financially supported by a grant from the National Science Center Poland (Narodowe Centrum Nauki): „ Bathymetric surveys of lakes on King George Island (South Shetland Islands, West Antarctica)” no. 2024/08/X/ST10/00760. The research was conducted with the support of the Henryk Arctowski Polish Antarctic Station. For more information please contact: Joanna Plenzler; joannapl@ibb.waw.pl

All papers, theses, abstracts and presentations created based on this data, either wholly or in part, should include the following sentence in the acknowledgements or dedicated section of the work: ‘This work was created using the infrastructure of the Henryk Arctowski Polish Antarctic Station’.