0df5d4e9-2fcd-4420-b403-24d76848a5a5 eng utf8 dataset dataset NERC EDS UK Polar Data Centre +44 (0)1223 221400 British Antarctic Survey, High Cross, Madingley Road Cambridge Cambridgeshire CB3 0ET United Kingdom polardatacentre@bas.ac.uk https://www.bas.ac.uk/team/business-teams/information-services/uk-polar-data-centre/ information pointOfContact 2024-05-31 ISO 19115 Geographic Information - Metadata ISO 19115:2003(E) European Petroleum Survey Group (EPSG) Geodetic Parameter Registry 2008-11-12 publication European Petroleum Survey Group EPSGadministrator@iogp.org https://www.epsg-registry.org/ EPSG Geodetic Parameter Dataset The EPSG Geodetic Parameter Dataset is a structured dataset of Coordinate Reference Systems and Coordinate Transformations, accessible through this online registry. information publisher urn:ogc:def:crs:EPSG::3031 6.18.3 Subglacial water flow paths beneath Whillans Ice Plain, West Antarctica 2024-05-31 creation 2024-05-31 revision 2024-05-31 publication 2024-05-31 released 1.0 https://doi.org/10.5285/0df5d4e9-2fcd-4420-b403-24d76848a5a5 doi GB/NERC/BAS/PDC/01854 https://data.bas.ac.uk/ NE/T00939X/1 award Please cite this item as: Sauthoff, W., & Freer, B. (2024). Subglacial water flow paths beneath Whillans Ice Plain, West Antarctica (Version 1.0) [Data set]. NERC EDS UK Polar Data Centre. https://doi.org/10.5285/0df5d4e9-2fcd-4420-b403-24d76848a5a5 This dataset provides a geopackage of the predicted subglacial water flow pathways beneath Whillans Ice Plain, West Antarctica, the contributory Whillans Ice Stream and neighbouring Kamb and Mercer Ice Streams. Flow paths were estimated based on hydropotential gradients using static grids of ice-surface elevation from the REMA mosaic (Howat and others, 2019) and ice thickness from Bedmachine Antarctica version 3 (Morlighem and others, 2020; 2022) from which bed elevation is inferred. Wilson Sauthoff (dataset creator) was funded by NASA award 80NSSC21K0912. Bryony I. D. Freer (project lead) was supported by Natural Environment Research Council (NERC) Satellite Data in Environmental Science (SENSE) Centre for Doctoral Training (grant no. NE/T00939X/1). No credit. completed Sauthoff, Wilson Colorado School of Mines Researcher author Freer, Bryony British Antarctic Survey Researcher author NERC EDS UK Polar Data Centre +44 (0)1223 221400 British Antarctic Survey, High Cross, Madingley Road Cambridge Cambridgeshire CB3 0ET United Kingdom PDCServiceDesk@bas.ac.uk https://www.bas.ac.uk/team/business-teams/information-services/uk-polar-data-centre/ information pointOfContact asNeeded completed EARTH SCIENCE > Hydrosphere > Ground Water > Ground Water Discharge/Flow EARTH SCIENCE > Cryosphere > Snow/Ice theme Global Change Master Directory (GCMD) Science Keywords 2026-01-27 publication 23 Global Change Data Center, Science and Exploration Directorate, Goddard Space Flight Center (GSFC) National Aeronautics and Space Administration (NASA) Greenbelt MD United States of America https://earthdata.nasa.gov/about/gcmd/global-change-master-directory-gcmd-keywords Global Change Master Directory (GCMD) Keywords The information provided on this page seeks to define how the GCMD Keywords are structured, used and accessed. It also provides information on how users can participate in the further development of the keywords. information publisher Antarctica Engelhardt Subglacial Lake Siple Coast Subglacial hydrology Whillans Ice Plain flow paths subglacial lakes theme Whillans Ice Plain Antarctica Whillans Ice Stream Antarctica Kamb and Mercer Ice Streams Antarctica place Hydrography Meteorological geographical features theme GEMET - INSPIRE themes, version 1.0 2021-01-06 revision otherRestrictions no limitations to public access otherRestrictions no limitations license Open Government Licence v3.0 otherRestrictions None doi doi dependency doi doi crossReference doi doi crossReference doi doi crossReference doi doi crossReference doi doi crossReference doi doi crossReference url url crossReference textTable eng utf8 geoscientificInformation -174.33 -97.58 -88.3 -79.54 1961-01-01 2021-12-31 2446.31 3805.99 urn:ogc:def:crs:EPSG::5714 MSL height Not specific to any location or epoch. Hydrography. It is recommended that careful attention be paid to the contents of any data, and that the author be contacted with any questions regarding appropriate use. If you find any errors or omissions, please report them to polardatacentre@bas.ac.uk. NERC EDS UK Polar Data Centre +44 (0)1223 221400 British Antarctic Survey, High Cross, Madingley Road Cambridge Cambridgeshire CB3 0ET United Kingdom PDCServiceDesk@bas.ac.uk https://www.bas.ac.uk/team/business-teams/information-services/uk-polar-data-centre/ information distributor application/octet-stream application/geopackage+sqlite3 bytes 1048576 http://ramadda.data.bas.ac.uk/repository/entry/show?entryid=0df5d4e9-2fcd-4420-b403-24d76848a5a5 WWW:LINK-1.0-http--link Get Data Download data download bytes 1048576 http://ramadda.data.bas.ac.uk/repository/entry/show?entryid=0df5d4e9-2fcd-4420-b403-24d76848a5a5 WWW:LINK-1.0-http--link Get Data Download data download dataset Methodology: We used static grids of ice surface elevation from the REMA mosaic (Howat and others, 2019) and ice thickness (from which bed elevation is inferred; Morlighem and others, 2020; 2022) to predict the subglacial water flow routing pathways based on hydropotential gradients. Hydropotential gradients control where water is driven to flow by gravitational potential (bed elevation) and ice overburden pressure (Shreve, 1972), given by equation 1: del-phi = rho . g . del-z . del-Pw where phi is the hydropotential gradient, rho is the density of water, g is gravitational acceleration, z is bed elevation, and Pw is water pressure. Pw assumes effective pressure (N) is zero, which is a common assumption in subglacial hydrology where effective pressure is challenging to measure. Instead Pw is calculated solely from the depth of the ice column above. Flow routing pathways were modelled based on the hydropotential surface using the Python package, pysheds release 0.3.5 (Bartos, 2020). We conditioned the hydropotential surface by pit and depression filling and resolved flats. Flow direction and accumulation used the default directional mapping that specifies the routing algorithm. We extracted flow paths with flow accumulations >1,000 upstream cells. Flow paths were clipped at the grounding line (Depoorter and others, 2013) and filtered to only include flow paths intersecting the region of interest (Whillans Ice Plain, West Antarctica, the contributory Whillans Ice Stream and neighbouring Kamb and Mercer Ice Streams). Computation was conducted using a ~32 GB server on CryoCloud cloud-computing hub (Snow and others, 2023). Temporal coverage: * We used static grids of ice surface elevation from BedMachine Antarctica, Version 3 (Morlighem and others, 2020; 2022) that uses the REMA mosaic (Howat and others, 2019), which was created with sub-meter resolution Maxar optical satellite imagery acquired across multiple austral summer seasons between 2009 and 2021. * We used static grids of ice thickness from BedMachine Antarctica, Version 3 (Morlighem and others, 2020; 2022). BedMachine Antarctica uses a variety of input datasets with temporal coverage spanning 1961 to 2020. Location: The dataset covers the region of interest, the Whillans Ice Plain, plus the upstream ice drainage basin of Whillans Ice Stream and neighbouring Kamb and Mercer Ice Streams as defined in the refined basins in the MEaSUREs Antarctic Boundaries for IPY 2007-2009 from Satellite Radar, Version 2 dataset (Mouginot and others, 2017). CRS: Polar stereographic projection (?EPSG:3031?) Data collection: To generate the predicted subglacial flow paths, we used the Python package, pysheds release 0.3.5 (Bartos, 2020). Data quality: Ice-surface elevations from REMA (Howat and others, 2019) have relatively low error, typically less than 1 m. Sources of error in BedMachine Antarctica's estimates of ice thickness and thus bed elevation include error in ice velocity direction and magnitude, error in surface mass balance, and ice thinning rates. Below grounded ice, the error in mass conservation derived ice thickness and bed elevation ranges from 36 m to exceeding 200 m based on the density radar sounding coverage (Morlighem and others, 2020; 2022). Within the region of subglacial flow path mapping, BedMachine Antarctica has a mean error of 74.8 m and a maximum error of 786.0 m, which is most prominent in the upper catchment of Kamb Ice Stream. asNeeded completed