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  • During the austral summer of 2001/02 five thousand line kilometres of airborne radio echo sounding and aeromagnetic data were collected in the region of three tributaries of Slessor Glacier, East Antarctica, which drains into the Filchner Ice Shelf. We present here the processed bed elevation picks from airborne radar depth sounding acquired using the BAS aerogeophysicaly equipped Twin Otter aircraft. Data are provided as XYZ ASCII line data. Data were collected as part of UK Natural Environment Research Council (NERC) grant GR3/AFI2/65

  • A British Antarctic Survey Twin Otter and survey team acquired 15,500 line-km of aerogeophysical data during the 2001/02 Antarctic field season along a 1-km line spacing grid with tie-lines 8 km apart. Twenty-five flights were flown from the South African base SANAE, for a total of 100 survey hours. We present here the processed bed elevation picks from airborne radar depth sounding. The airborne-radio echosounding data were collected for 5 flights, to image ice-thickness and bedrock configuration. Data are provided as XYZ ASCII line data. This high-resolution aerogeophysical survey was part of the "Magmatism as a Monitor of Gondwanabreak-up" project (MAMOG) of the British Antarctic Survey, which included new geochemical investigations, structural geology, geochronology, and AMS studies over western Dronning Maud Land.

  • During the 2001-02 field season a regional survey was flown on a 10 km line spacing grid over the drainage basin of the Rutford Ice stream (West Antarctica), as part of the TORUS (Targeting ice stream onset regions and under-ice systems) project. We present here the bed elevation picks from airborne radar depth sounding collected using the "BAS-built" radar depth sounding system mounted on the BAS aerogeophysical equipped Twin Otter aircraft. Data are provided as XYZ ASCII line data

  • During the 2010/2011 Antarctic field season a collaborative NERC AFI (Antarctic Funding Initiative) project studying the basal boundary conditions of the Institute & Moller ice streams, West Antarctica, collected ~25,000 km of new high quality aerogeophysics data. Data were acquired using the BAS PASIN depth sounding radar mounted in the BAS aerogeophysically equipped Twin Otter "Bravo Lima". Data are provided as XYZ ASCII line data. Data were collected as part of the UK Natural Environment Research Council AFI grant NE/G013071/1.

  • During the austral summer of 2015/16, a major international collaboration 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), acquired ~38,000 line km of aerogeophysical data. The primary objective of the POLARGAP campaign was to carry out an airborne gravity survey covering the southern polar gap of the ESA gravity field mission GOCE, beyond the coverage of the GOCE orbit (south of 83.5degS), however aeromagnetics and ice-penetrating radar data were also opportunistically acquired. This survey covers the South Pole and Recovery Lakes, as well as parts of the Support Force, Foundation and Recovery Glaciers. Our Twin Otter 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 a new ice-sounding radar system (PASIN-2). 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 is Version 2 of the dataset. This version differs from Version 1, as follows: 1. The variables "fast_time" and "UTC_time_layerData" have been updated due to errors found. The error in the fast_time variable related to an error in the sampling frequency of the system, which should have been 24 MHz instead of 22MHz. This has been updated. The error in the "UTC_time_layerData" related to a rounding issue which affected the precision of this variable. This has been updated. 2. The units in the "surface_pick_layerData" and the "bed_pick_layerData" variables should have been "samples relative to the BAS radar system", instead of "microseconds". This has been corrected. 3. The metadata in this DMS entry and in the NetCDF files has also been updated. Mainly, the sampling frequency has been modified from 22 MHz to 24 MHz to reflect the radar system characteristics. This also affected the value provided for the radar system resolution and sampling interval, which have both been updated in the metadata. 4. The SEGY sampling interval value (byte numbers: 117-118 (SI)) has also been updated to reflect the change in sampling frequency mentioned above. All other variables remain unchanged. Note that these changes do not affect the radar data or the associated radar-derived data in the files.

  • Three separate airborne radar surveys were flown during the austral summer of 2016/17 over the Filchner Ice Shelf and Halley Ice Shelf (West Antarctica), and over the outlet glacier flows of the English Coast (western Palmer Land, Antarctic Peninsula) during the Filchner Ice Shelf System (FISS) project. This project was a NERC-funded (grant reference number: NE/L013770/1) collaborative initiative between the British Antarctic Survey, the National Oceanography Centre, the Met Office Hadley Centre, University College London, the University of Exeter, Oxford University, and the Alfred Wenger Institute to investigate how the Filchner Ice Shelf might respond to a warmer world, and what the impact of sea-level rise could be by the middle of this century. The 2016/17 aerogeophysics surveys acquired a total of ~26,000 line km of aerogeophysical data. The FISS survey consisted of 17 survey flights totalling ~16,000 km of radar data over the Support Force, Recovery, Slessor, and Bailey ice streams of the Filchner Ice Shelf. The Halley Ice Shelf survey consisted of ~4,600 km spread over 5 flights and covering the area around the BAS Halley 6 station and the Brunt Ice Shelf. The English Coast survey consisted of ~5,000 km spread over 7 flights departing from the Sky Blu basecamp and linking several outlet glacier flows and the grounding line of the western Palmer Land, including the ENVISAT, CRYOSAT, GRACE, Landsat, Sentinel, ERS, Hall, Nikitin and Lidke ice streams. Our Twin Otter aircraft was equipped with dual-frequency carrier-phase GPS for navigation, radar altimeter for surface mapping, wing-tip magnetometers, an iMAR strapdown gravity system, and a new ice-sounding radar system (PASIN-2). 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 is Version 2 of the dataset. This version differs from Version 1, as follows: 1. The variables "fast_time" has been updated due to errors found. The error in the variable related to an error in the sampling frequency of the system, which should have been 24 MHz instead of 22MHz. This has been updated. 2. The units in the "surface_pick_layerData" and the "bed_pick_layerData" variables should have been "samples relative to the BAS radar system", instead of "microseconds". This has been corrected. 3. The metadata in this DMS entry and in the NetCDF files has also been updated. Mainly, the sampling frequency has been modified from 22 MHz to 24 MHz to reflect the radar system characteristics. This also affected the value provided for the radar system resolution and sampling interval, which have both been updated in the metadata. 4. The SEGY sampling interval value (byte numbers: 117-118 (SI)) has also been updated to reflect the change in sampling frequency mentioned above. All other variables remain unchanged. Note that these changes do not affect the radar data or the associated radar-derived data in the files.

  • This data set corresponds to data acquired by the British Antarctic Survey (BAS) airborne Synthetic Aperture Radar (SAR) PASIN2 (Polarimetric Airborne Scientific INstrument, mark 2), designed for deep ice sounding and basal 3d-mapping. The data set includes the processed SAR images as depth profiles in the Recovery Ice Stream and Rutford Ice Stream, respectively downstream and upstream of the grounding line, and respectively for the 2016/17 FISS (Filchner Ice Shelf System) and the 2019/20 BEAMISH (Bed Access, Monitoring and Ice Sheet History) projects, both during the Antarctic Summer. With multiple antennas for transmission and reception at 150-MHz central frequency, and an across-track physical array, PASIN2 resolves the ambiguities for distinguishing between scatterers from port and starboard directions; however, in the two SAR images of the current dataset the port/starboard ambiguities are not resolved. On this dataset the user will be able to apply the RGB Doppler Decomposition method in the Doppler domain, interpret the results, and modify the different parameters and colours to contrast the results, all with the outcome of conducting new decompositions according to other datasets and needs. The RGB Spectral Decomposition is a generalised framework to interpret the SAR images: first, the Doppler or range spectral domains are first split into three sub-bandwidths; next, to each of the three a colour of a triplet of colours is assigned; and finally the three are superposed into one single image by the addition of the three colours. If the decomposition is applied on the Doppler spectrum, the new image contains the directional information related to the Doppler frequencies: positive frequencies when the radar approaches the target, near zero frequencies when the relative distance from radar to target is near stationary, and negative when the radar leaves it behind. If the backscattering is characterised by a very broad beamwidth the target will be gray/white, and if by a very narrow beamwidth then the target will be represented by one of the colours of the triplet. This work has received funding from the NERC grant NE/L013444/1, project: Ice shelves in a warming world: Filchner Ice Shelf System (FISS), Antarctica. The 2016/17 data were collected as part of the NERC grant NE/L013770/1, project: Ice shelves in a warming world: Filchner Ice Shelf System (FISS), Antarctica. The 2019/20 data were collected as part of the BAS National Capability contribution to the NERC/NSF International Thwaites Glacier Collaboration (ITGC) program.

  • During the austral summer of 2004/05 a collaborative US/UK field campaign undertook a systematic geophysical survey of the entire Amundsen Sea embayment using comparable airborne survey systems mounted in Twin Otter aircraft. Here we present the portion of the survey covering the Pine Island Glacier basin led by British Antarctic Survey. Operating from a temporary field camp (PNE, S 77deg34'' W 095deg56''); we collected ~35,000 km of airborne survey data. Our aircraft was equipped with dual-frequency carrier-phase GPS for navigation, radar altimeter for surface mapping, wing-tip magnetometers, gravity meter, and a new ice-sounding radar system (PASIN). We present here the bed elevation picks from airborne radar depth sounding collected using the BAS PASIN radar depth sounding system. Data are provided as XYZ ASCII line data.

  • During the austral summer of 2015/16, a major international collaboration 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), acquired ~38,000 line km of aerogeophysical data. The primary objective of the POLARGAP campaign was to carry out an airborne gravity survey covering the southern polar gap of the ESA gravity field mission GOCE, beyond the coverage of the GOCE orbit (south of 83.5degS), however aeromagnetics and ice-penetrating radar data were also opportunistically acquired. This survey covers the South Pole and Recovery Lakes, as well as parts of the Support Force, Foundation and Recovery Glaciers. Our Twin Otter 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 a new ice-sounding radar system (PASIN-2). 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. NOTE: Please note that an issue with the floats in the NetCDF variable "UTC_time_layerData" has resulted in this variable having rounded up decimal numbers. In order to fix this issue, we advise users who need this variable to download the separately published bed pick data for the POLARGAP survey (doi: https://doi.org/10.5285/d55e87dd-a74d-4182-be99-93ab805103ab) and use the ''DateTime_YYYY-MM-DD_HH:MM:SS.S'' column which is the same as the one used to produce the NetCDF.

  • 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.