Processed airborne radio-echo sounding data for the Thwaites Glacier 2019 survey, West Antarctica (2019/2020) ...

• Main Authors: Jordan, Tom, Robinson, Carl
• Format: Dataset
• Language: English
• Published: NERC EDS UK Polar Data Centre 2021
• Subjects: "EARTH SCIENCE","CRYOSPHERE","SNOW/ICE","ICE DEPTH/THICKNESS"; "EARTH SCIENCE","HYDROSPHERE","GLACIERS/ICE SHEETS","GLACIER THICKNESS/ICE SHEET THICKNESS"; "EARTH SCIENCE","CRYOSPHERE","GLACIERS/ICE SHEETS"; Antarctica; Geophysics; FOS Earth and related environmental sciences; ITGC; Radar; Thwaites Glacier; aerogeophysics; ice thickness; surface elevation; Antarctic; West Antarctica; Antarc*; British Antarctic Survey; Ice Sheet
• Online Access: https://dx.doi.org/10.5285/e7aba676-1fdc-4c9a-b125-1ebe6124e5dc; https://data.bas.ac.uk/full-record.php?id=GB/NERC/BAS/PDC/01322

As part of the International Thwaites Glacier Collaboration (ITGC) ~4432 km of new radar depth sounding data was acquired over the Thwaites Glacier catchment by the British Antarctic Survey. Data was collected using the PASIN-2 polametric radar system, fitted on the BAS aerogeophysical equipped survey aircraft "VP-FBL". The survey operated from Lower Thwaites Glacier camp, and focused on collecting data in regions of ice >1.5 km thick between 70 and 180 km from the grounding line. Additional profiles from the coast to the Western Antarctic Ice Sheet (WAIS) divide and over the eastern shear margin were also flown. Ice thicknesses between 418 and 3744 m were measured, with a minimum bed elevation of -2282 m imaged. 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 ... : ** Instrumentation and Processing: Radar data were collected using the new bistatic PASIN-2 radar echo sounding system mounted on the BAS Twin Otter aircraft "VP-FBL" and operating with a centre frequency of 150 MHz and using a 4-microseconds, 13 MHz bandwidth linear chirp. The PASIN system transmitted 5 separate pulses from the wing arrays as follows; Port 4 microseconds chirp; Starboard 4 microseconds chirp; Port 4 microseconds chirp 180deg phase shift; Starboard 4 microseconds chirp 180deg phase shift; Port 1 microseconds chirp. Data for every antenna and pulse is recorded separately, in 20 second segments. Chirp compression was applied using a Blackman window to minimise sidelobe levels, resulting in a processing gain of 10 dB. The chirp data was processed using a coherent averaging filter (commonly referred to as unfocused Synthetic Aperture Radar (SAR) processing) with Doppler beam sharpening to enhance the signal to clutter ratio of the bed echo and improve visualisation. The chirp data is best suited ...