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  • We present here the Bedmap3 ice thickness, bed and surface elevation aggregated points and survey lines. The aggregated points consist of statistically-summarised shapefile points (centred on a continent-wide 500 m x 500 m grid) that reports the average values of Antarctic ice thickness, bed and surface elevation from the full-resolution survey data and information on their distribution. The points presented here correspond to the added points since the last release of Bedmap2. The data comes from 14 different data providers and 75 individual surveys. They are available as geopackages and shapefiles. The associated Bedmap datasets are listed here: https://www.bas.ac.uk/project/bedmap/#data This work is supported by the SCAR Bedmap project and the British Antarctic Survey''s core programme: National Capability - Polar Expertise Supporting UK Research

  • This dataset contains bed and surface elevation picks derived from airborne radar collected during the POLARGAP 2015/16 project funded by the European Space Agency (ESA) and with in-kind contribution from the British Antarctic Survey, the Technical University of Denmark (DTU), the Norwegian Polar Institute (NPI) and the US National Science Foundation (NSF). This collaborative project collected ~38,000 line-km of new aerogeophysical data using the 150MHz PASIN radar echo sounding system (Corr et al., 2007) deployed on a British Antarctic Survey (BAS) Twin Otter. The primary objective of the POLARGAP campaign was to carry out an airborne gravity survey covering the southern polar gap beyond the coverage of the GOCE orbit. This dataset covers the South Pole as well as parts of the Support Force, Foundation and Recovery Glaciers. The bed pick data acquired during the POLARGAP survey over the Recovery Lakes is archived at NPI: https://doi.org/10.21334/npolar.2019.ae99f750.

  • During the austral summer of 2012/13 a major international collaboration between Danish, US, UK, Norwegian and Argentinian scientists collected ~29,000 line km (equivalent to 464,317 km2) of aerogeophysical data over 132 hours of flight time and covering the previously poorly surveyed Recovery Glacier and Recovery Subglacial Lakes, as well as the area of Coats Land inboard from Halley VI using airborne survey systems mounted in Twin Otter aircraft. Our aircraft was equipped with dual-frequency carrier-phase GPS for navigation, radar altimeter for surface mapping, wing-tip magnetometers, an air-sea gravity meter, and an ice-sounding radar system (PASIN). We present here the full radar dataset consisting of the deep-sounding chirp in its processed form, as well as the navigational information of each trace, the surface and bed elevation picks, ice thickness, and calculated absolute surface and bed elevations. This dataset comes primarily in the form of NetCDF and georeferenced SEGY files. To interactively engage with this newly-published dataset, we also created segmented quicklook PDF files of the radar data.

  • This dataset includes ~3,000 line km of radio-echo sounding data along the English Coast of western Palmer Land in the Antarctic Peninsula. Data was acquired by the British Antarctic Survey Polarimetric-radar Airborne Science Instrument (PASIN2) ice sounding radar system in the austral summer of 2016/2017. Radar lines collected at ~3-5 km line spacing transect a number of outlet glacier flows, close to the grounding line, where continental ice begins to float. Data were funded by a BAS National Capability grant.

  • We use polarimetric radar sounding to investigate variation in ice crystal orientation fabric within the near-surface (top 40-300 m) of Rutford Ice Stream, West Antarctica. To assess the influence of the fabric on ice flow, we use an analytical model to derive anisotropic enhancements of the flow law from the fabric measurements. In the shallowest ice (40-100 m) the azimuthal fabric orientation is consistent with flow-induced development and correlates with the surface strain field. Notably, toward the ice-stream margins, both the horizontal compression angle and fabric orientation tend toward 45 degrees relative to ice flow. This result is consistent with theoretical predictions of flow-induced fabric under simple shear, but to our knowledge has never been observed. The fabric orientation in deeper ice (100-300 m) is significantly misaligned with shallower ice in some locations, and therefore inconsistent with the local surface strain field. This result represents a new challenge for ice flow models which typically infer basal properties from the surface conditions assuming simplified vertical variation of ice flow. Our technique retrieves azimuthal variations in fabric but is insensitive to vertical variation, and we therefore constrain the fabric and rheology within two end-members: a vertical girdle or a horizontal pole. Our hypotheses are that fabric near the center of the ice-stream tends to a vertical girdle that enhances horizontal compression, and near the ice-stream margins tends to a horizontal pole that enhances lateral shear. ApRES radar data were collected as part of the BEAMISH Project (NERC AFI award numbers NE/G014159/1 and NE/G013187/1). Tom Jordan would like to acknowledge support from EU Horizon 2020 grant 747336-BRISRES-H2020-MSCA-IF-2016.

  • The EISCAT (European Incoherent Scatter ) data is from either the Ultra High Frequency (UHF) or Very High Frequency (VHF) radar observations of Polar Mesospheric Summer Echoes/Winter Echoes (PMSE/PMWE). The data archive contains EISCAT UHF or VHF radar data, processed with GUISDAP (Grand Unified Incoherent Scatter Design and Analysis Package) analysis software, of electron density, ion temperature, electron temperature or ion velocity as a function of altitude along with estimates of their uncertainty. The time and range resolution is variable depending on the analysis settings. Data was collected in July 2012, June-July 2013, June-July 2014 and November 2014.

  • During the austral summer of 2005/06 a collaborative UK/Italian field campaign collected ~61,000 line km of aerogeophysical data over the previously poorly surveyed Wilkes subglacial basin, Dome C, Transantarctic Mountains, George V Land and Northern Victoria Land using airborne survey systems mounted in a Twin Otter aircraft. Our aircraft was equipped with dual-frequency carrier-phase GPS for navigation, radar altimeter for surface mapping, wing-tip magnetometers, a LaCoste and Romberg air-sea gravimeter, and an ice-sounding radar system (PASIN). We present here the full radar dataset consisting of the deep-sounding chirp and shallow-sounding pulse-acquired data in their processed form, as well as the navigational information of each trace, the surface and bed elevation picks, ice thickness, and calculated absolute surface and bed elevations. This dataset comes primarily in the form of NetCDF and georeferenced SEGY files. To interactively engage with this newly-published dataset, we also created segmented quicklook PDF files of the radar data.

  • This data set contains bed and surface elevation picks derived from airborne radar collected during the WISE/ISODYN project. This collaborative UK/Italian project collected ~ 61000 line km of new aerogeophysical data during the 2005/2006 austral summer, over the previously poorly surveyed Wilkes subglacial basin, Dome C, George V Land and Northern Victoria Land.

  • An airborne radar survey was flown over the Institute and Moller ice streams in the Weddell Sea sector of West Antarctica in the austral summer of 2010/11 as part of the Institute-Moller Antarctic Funding Initiative (IMAFI) project (grant reference number: NE/G013071/1). This project was a NERC Antarctic Funding Initiative (AFI) collaborative project between the British Antarctic Survey and the Universities of Edinburgh, York, Aberdeen and Exeter with the aim to test the hypothesis that the Institute and Moller ice streams are underlain by weak marine sediments which control the flow of the overlying ice. Operating from two static field camps close to the ice divide between the Institute and Moller ice streams and Patriot Hills, we collected ~25,000 km of airborne radio-echo sounding data across 28 survey lines. Our aircraft was equipped with dual-frequency carrier-phase GPS for navigation, radar altimeter for surface mapping, wing-tip magnetometers, a LaCoste and Romberg air-sea gravimeter, and an ice-sounding radar system (PASIN). We present here the full radar dataset consisting of the deep-sounding chirp and shallow-sounding pulse-acquired data in their processed form, as well as the navigational information of each trace, the surface and bed elevation picks, ice thickness, and calculated absolute surface and bed elevations. This dataset comes primarily in the form of NetCDF and georeferenced SEGY files. To interactively engage with this newly-published dataset, we also created segmented quicklook PDF files of the radar data.

  • An airborne radar survey was flown as part of the seven nation Antarctica''s Gamburtsev Province (AGAP) expedition over the Gamburtsev Subglacial Mountains, Dome A, and the interior of East Antarctica during the International Polar Year 2007-2009. Operating from field camps located on either side of Dome A (namely AGAP-N and AGAP-S), we collected ~120,000 km (equivalent to 180,000 km2) of airborne survey data using two Twin Otter aircrafts - one from BAS and one from the United States Antarctic Program (USAP). The aircrafts were equipped with dual-frequency carrier-phase GPS for navigation, laser ranging systems, magnetometers, gravity meters, and ice-sounding radars. We present here the full radar dataset from the BAS PASIN radar system consisting of the deep-sounding chirp and shallow-sounding pulse-acquired data in their processed form, as well as the navigational information of each trace, the surface and bed elevation picks, ice thickness, and calculated absolute surface and bed elevations. This dataset comes primarily in the form of NetCDF and georeferenced SEGY files. To interactively engage with this newly-published dataset, we also created segmented quicklook PDF files of the radar data.