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EARTH SCIENCE > Spectral/Engineering > Radar

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  • 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.

  • 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.

  • A new version of this dataset exists. Please have a look at: Corr, H., Robinson, C., Jordan, T., Nicholls, K., Brisbourne, A., & Bodart, J. (2024). Processed airborne radio-echo sounding data from the FISS 2016 surveys covering the Filchner and Halley Ice Shelves, and the English Coast (western Palmer Land), West Antarctica (2016/2017) (Version 2.0) [Data set]. NERC EDS UK Polar Data Centre. https://doi.org/10.5285/e203926b-7a54-4c33-a5df-04df2293d7d3 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.

  • A new version of thhis dataset exists. Please have a look at: Nicholls, K., Robinson, C., Corr, H., Jordan, T., & Bodart, J. (2024). Processed airborne radio-echo sounding data from the FISS 2015 survey covering the Foundation Ice Stream, Bungenstock Ice Rise and the Filchner Ice Shelf system, West Antarctica (2015/2016) (Version 2.0) [Data set]. NERC EDS UK Polar Data Centre. https://doi.org/10.5285/ef482413-623b-4e71-a054-d394fc28ed54 An airborne radar survey was flown during the austral summer of 2015/16 over the Foundation Ice Stream, Bungenstock Ice Rise, and the Filchner ice shelf as part of the 5-year 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 2015/16 aerogeophysics survey acquired ~7,000 line km of aerogeophysical data with a particular focus on the Foundation Ice Stream. Our Twin Otter aircraft was equipped with dual-frequency carrier-phase GPS for navigation, radar altimeter for surface mapping, wing-tip magnetometers, 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 dataset contains bed and surface elevation picks derived from airborne radar collected in 2016/17 over the Filchner Ice Shelf and Halley Ice Shelf (West Antarctica) as part of the 5-year Filchner Ice Shelf System (FISS) project funded by NERC (grant reference number: NE/L013770/1) and awarded to the British Antarctic Survey with contribution from the National Oceanography Centre, the Met Office Hadley Centre, University College London, the University of Exeter, Oxford University, and the Alfred Wenger Institute. The aim of this project was 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. This collaborative initiative collected ~15,000 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 majority of flights were flown as part of FISS over the Support Force, Recovery, Slessor, and Bailey ice streams. Separate flights over Halley 6 research station and Brunt Ice Shelf were also collected as part of this season. The bed and surface elevation picks for the English Coast part of this season are available at: https://doi.org/10.5285/e07d62bf-d58c-4187-a019-59be998939cc.

  • This dataset contains bed and surface elevation picks derived from airborne radar collected in 2015/16 over Foundation Ice Stream and Filchner Ice Shelf as part of the 5-year Filchner Ice Shelf System (FISS) project funded by NERC (grant reference number: NE/L013770/1) and awarded to the British Antarctic Survey with contribution from the National Oceanography Centre, the Met Office Hadley Centre, University College London, the University of Exeter, Oxford University, and the Alfred Wenger Institute. The aim of this project was 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. This collaborative initiative collected ~7,000 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 data set comprises ionospheric vorticity estimates determined from measurements of ionospheric velocity made by overlapping pairs of northern hemisphere radars in the Super Dual Auroral Radar Network (SuperDARN). The vorticity estimates are separated into data files for each pair of SuperDARN radars that contributed to the whole data set. These data cover large regions of the northern hemisphere polar ionosphere, and the locations of the vorticity estimates are presented in both geographic and Altitude-Adjusted Corrected GeoMagnetic (AACGM) co-ordinates. The data cover the interval from 2000 to 2005 inclusive. This work was funded by NERC grant reference NE/R016038/1.

  • This dataset contains data from three ground-penetrating radar surveys undertaken to image ice thickness and englacial stratigraphy during the 2019-20 Antarctic field season, as part of the International Thwaites Glacier Collaboration (funded by NERC and NSF). The ground-penetrating radar data are presented as SEG-Y, along with the GPS tracks of the surveys, presented as GPS Exchange Format (GPX). The subglacial extensions of ridges of three nunataks close to Pine Island and Larter Glaciers in the Hudson Mountains region were surveyed, with the aim of determining their suitability as subglacial bedrock drill sites. Those nunataks are Winkie Nunatak (74 degrees 51' 41.0" S/99 degrees 46' 49.4" W), Evans Knoll (74 degrees 51' 00.0" S/100 degrees 25' 00.0" W), and Webber Nunatak (74 degrees 47' 00.0" S/99 degrees 50' 00.0" W). This work was funded by NERC grants NE/S00663X/1 and NE/S006710/1.

  • 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. ***** PLEASE BE ADVISED THIS DATA SET HAS BEEN RETRACTED ***** This data set had incorrect coordinates for one of the sites. In addition, some files were incorrectly labelled as belonging to one of the sites A new data set (see 'Related Data Set Metadata' link below) addresses these issues and also includes significant additional data, as well as updated metadata and additional authors. Hence it is a wholly new data set, rather than an updated version of this data set. Please use this new data set instead.

  • This dataset includes double-difference interferograms derived from TerraSAR-X synthetic aperture radar data acquired at the grounding line downstream of Engelhardt Subglacial Lake on the Gould Coast, Antarctica, in September 2012, April 2016, July 2023 and October 2023. The September 2012, July 2023 and October 2023 interferograms were generated by Oliver J. Marsh (British Antarctic Survey) using the Gamma Remote Sensing software and geocoded with the Bedmap2 DEM. The April 2016 interferogram was generated by Dana Floricioiu (DLR, German Aerospace Center) using DLR's Integrated Wide Area Processor (IWAP; Rodriguez et al, 2013). The image processing information, acquisition time and coincident modelled tide heights for all data used to derive the TerraSAR-X interferograms are provided in the lineage section. For each interferogram (September 2012, April 2016, July 2023 and October 2023) we provide a shapefile of the derived grounding line, which was manually traced along the landward boundary of the dense fringe belt associated with the vertical tidal motion of the ice (Point F). This dataset was produced as part of the study: Freer et al. (2024) Synchronous lake drainage and grounding line retreat at Engelhardt Subglacial Lake, West Antarctica. Journal of Geophysical Research: Earth Surface. Funding: 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). Dana Floricioiu (dataset creator) was supported by DLR's Polar Monitor II and Antarctic Ice Sheet CCI projects (ESA/Contract No. 4000126813/18/I-NB). Images were acquired under DLR TerraSAR-X science data proposal HYD3673 (PI Dana Floricioiu).