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  • The dataset lists information about the instrumentation of boreholes drilled into Khumbu Glacier, Nepal. Boreholes were drilled in May 2017 and May 2018 to investigate the internal properties of Khumbu Glacier, specifically ice thickness, temperature, deformation and structure, as part of the NERC-funded ''EverDrill'' research project. The information provided includes each borehole''s ID, length, location, elevation and instrumentation, including the type and depth of each sensor. Funding was provided by the NERC grant NE/P00265X/1 and NE/P002021/1.

  • The dataset lists information about boreholes drilled by hot water into Khumbu Glacier, Nepal. Boreholes were drilled in May 2017 and May 2018 to investigate the internal properties of Khumbu Glacier, specifically ice thickness, temperature, deformation and structure, as part of the NERC-funded ''EverDrill'' research project. The information provided includes each borehole''s ID, length, location (at the time of drilling), elevation and instrumentation. Funding was provided by the NERC grant NE/P00265X/1 and NE/P002021/1.

  • Model output from a series of idealised ice shelf-ocean simulations, demonstrating a new synchronously coupled modelling method as well as the response of ice shelf buttressing to melt under various temperature forcings.

  • The survey collected a total of 11,500 km of data along 22 lines, spaced 12 km apart and oriented perpendicular to the strike of both the Bouguer anomaly field, as derived from land data (McGibbon and Smith, 1991), and the major sub-ice topographical features (Doake et al., 1983). The speed of the aircraft was set to produce a sample spacing of about 60 m and the data were collected at heights between 1600 and 2000 m above sea level. The gravity signal was recorded using a LaCoste and Romberg air/sea gravimeter, S-83, which has been kindly loaned to BAS by the Hydrographic Office of the Royal Navy. The meter was modified by the ZLS company for use in an aircraft. The equipment was deployed in a BAS De-Havilland Twin Otter aircraft. Differential, dual frequency, carrier phase, GPS measurements of the aircraft''s motion were made using Trimble and Ashtech geodetic receivers and antennas. Ice thickness data were obtained using a BAS-built, radio echo sounding system (Corr and Popple, 1994). Ice-bottom returns over most of the survey area were obtained at a sample spacing of approximately 28 m. GPS measurements were tied into base stations in International Terrain Reference Frame network (Dietrich et al., 1998) and gravity measurements to base stations in the IGSN71 net (Jones and Ferris, 1999). We present here the processed bed elevation picks from airborne radar depth sounding collected using the BAS PASIN radar system. Data are provided as XYZ ASCII line data.

  • The data set was produced for the work detailed in ''The response of ice sheets to climate variability'' by K Snow et al (2017, Geophys Research Letters). A coupled ice sheet-ocean model is configured in an idealised setting with an inland-deepening bedrock, forced by far-field hydrographic profiles representative of the Amundsen Sea continental shelf. Similar to observed variability, the thermocline depth in the far-field is moved up and down on various times scales as detailed in the publication, with periods ranging from 2 to ~50 years. Bedrock elevation is provided, and annual melt rate and ice thickness (or sub-annual for short time scales) is provided as well for each forcing period. In addition, similar experiments were carried out with an ice-only model with parameterised forcing. These outputs are provided too.

  • The output of a 40-year coupled ice-ocean run of Smith Glacier, the adjoining Dotson and Crosson ice shelves, and the nearby continental shelf, with ocean boundary conditions forced with a climatology downscaled from a regional model of the Amundsen Sea. Funding was provided by the NERC Standard Grant NE/M003590/1 - Is ice loss from West Antarctica driven by ocean forcing or ice and ocean feedbacks?

  • This data set corresponds to the processing of 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 dataset includes the processed calibration data collected over the sea surface near Rothera Research Station during the Antarctic Summers campaigns in 2016/17 FISS (Filchner Ice Shelf System) and 2019/20 BEAMISH (Bed Access, Monitoring and Ice Sheet History) projects, and the processed SAR images as depth profiles in the Recovery Ice Stream near its grounding line, in 2016/17 (FISS). 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. After processing several 2D SAR images (range and along-track dimensions) with transmitter-receiver pairs, the directional ambiguities are resolved, obtaining the across-track Direction of Arrival (DoA, elevation angle) estimation. Finally, from the 3D geometry of range, along-track and across-track angle, the real depths and across-track distances are estimated, regarding the case of the incorrectly assumed vertical DoA of a single SAR image. The calibration flights assessed and validated the instrument antenna patterns and processing performances. In this dataset, only the simulated and measured antenna patterns, and SAR and DoA images are included. By resolving directional ambiguities and accounting for reflector across-track location, the true ice thickness and bed elevation are obtained, thereby removing the error of the usual assumption of vertical DoA, that greatly influence the output of flow models of ice dynamics. This work was supported by NERC grant reference NE/L013444/1.

  • SAR-processed two-dimensional radargram data in SEG-Y format acquired from the Institute and Moller ice streams, West Antarctica between mid-December 2010 and mid-January 2011. Data were collected using the British Antarctic Survey (BAS) Polarimetric radar Airborne Science Instrument (PASIN) radar, operated at a centre frequency of 150 MHz, and installed on the BAS Twin Otter aircraft "Bravo Lima". In total, ~25,000km of aerogeophysical data were collected, with coverage extending from the ice stream grounding zone to the ice divide. A high-resolution grid, with a line-spacing of 7.5 x 25 km, was acquired over the central parts of the ice stream catchments. Data were acquired during twenty-eight survey flights (sixteen flown from remote field camp C110, ten from Patriot Hills and two "transit" flights). Funding for this data acquisition was provided by the UK NERC AFI grant NE/G013071/1. These data should be cited as follows: Siegert, Martin et al. (2017); Synthetic-aperture radar (SAR) processed airborne radio-echo sounding data from the Institute and Moller ice streams, West Antarctica, 2010-11; Polar Data Centre, Natural Environment Research Council, UK; doi:10.5285/8a975b9e-f18c-4c51-9bdb-b00b82da52b8

  • The dataset consists of 14 selected lines of radar data, collected from the Little Dome C region close to Concordia Station in East Antarctica. The data were collected in austral field seasons 2016-17, and 2017-18, from within the search region for the planned European project Beyond EPICA - Oldest Ice, an EU-funded 10-nation consortium project to drill an ice core that spans up to 1.5 million years of climate and atmospheric history. Radar lines were recorded using the BAS DELORES sledge-borne, over-snow, ice radar system and geolocated with a precise GPS system. This data was generated within the project Beyond EPICA - Oldest Ice (BE-OI). The project has received funding from the European Union''s Horizon 2020 research and innovation programme under grant agreement No. 730258 (BE-OI CSA). It has received funding from the Swiss State Secretariat for Education, Research and Innovation (SERI) under contract number 16.0144. It is further supported by national partners and funding agencies in Belgium, Denmark, France, Germany, Italy, Norway, Sweden, Switzerland, the Netherlands and the UK. Logistic support is mainly provided by AWI, BAS, ENEA and IPEV. Collection of this data also benefited from support by the joint French-Italian Concordia Programme, which established and runs the permanent station Concordia at Dome C. We particularly acknowledge those who collected the data in the field, and assisted with the processing: Robert Mulvaney, Massimo Frezzotti, Marie Cavitte, Ed King, Carlos Martin, Catherine Ritz, Julius Rix.

  • An airborne radar survey was flown as part of the GRADES-IMAGE project funded by BAS over the Evans Ice stream/Carson Inlet region mainly to image englacial layers and bedrock topography during the 2006/07 field season. Aeromagnetic data were also opportunistically collected. 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.