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 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 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.

The dataset contains depth information (in meters) for pixels of subglacial overdeepenings with an area of 10000 m2 or larger, across five regions: Alaska, European Alps, New Zealand Southern Alps, the Central Himalayas, and the Peruvian Andes. These overdeepenings were derived by subtracting ice thickness data from Digital Elevation Models (DEMs) that describe the surface topography. Five ice thickness models were used for all regions: Farinotti's Ensemble, GlabTop2, Huss and Farinotti were downloaded from Farinotti et al., (2019). OGGM's ice thickness was downloaded from Farinotti et al., 2019 for all regions except for the Himalayas where it was generated by keeping the default same. Millan's ice thickness was downloaded from Millan et al., (2022). The primary DEM used was the ALOS PALSAR DEM. For Central Himalayas, in addition to ALOS PALSAR, three other DEMs were used: ASTER, SRTM, and Copernicus. NERC standard grant NE/S013318/1.

In 2011, aerogeophysics data were acquired over Pine Island Glacier, West Antarctica on a grid comprising 30 transverse lines across the glacier, each around 20 km long, and with a spacing of roughly 500 m between the lines. The orientation of the lines was selected to be perpendicular to the surface features visible in satellite images in the central part of the ice shelf. Elevation of the ice-surface directly beneath the aircraft was simultaneously measured using a nadir-pointing laser altimeter. 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.

This is a collection of all vintage BAS radar data that went into BEDMAP 1 (Lythe and Vaughan, 2001) that have not been released so far as line data. BEDMAP data describes the thickness of the Antarctic ice sheet. They have been collected on surveys undertaken over the past 50 years and brought together into a single database. These data have allowed the compilation of a suite of seamless digital topographic models for the Antarctic continent and surrounding ocean. Data are provided as XYZ ASCII line data.

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.

A British Antarctic Survey Twin Otter and survey team acquired 8,300 line-km of aerogeophysics data during the Austral summer of 1998/99. Gravity and radio-echo data were acquired simultaneously with the magnetic data at a compromise constant barometric height of 2,200 m, which provides a terrain clearance of 100 m over the highest peaks. Two separate surveys were conducted; one at 5 km line spacing (tie lines at 20 km) over and stretching beyond the southern extent of the Forrestal range (main survey), and one at 2 km line spacing (tie lines at 8 km) covering the Dufek Massif (detailed survey). Ashtech Z12 dual frequency GPS receivers were used for survey navigation. Pseudorange data were supplied to a Picodas PNAV navigation interface computer, which was used to guide the pilot along the pre-planned survey lines. The actual flight path was recovered, using carrier-phase, continuous, kinematic GPS processing techniques. All pseudorange navigation data were recorded at 1 Hz on a Picodas PDAS 1000, PC-based data acquisition system. We present here the processed bed elevation picks from airborne radar depth sounding collected using the "BAS-built" radar system (Corr and Popple, 1994; Fremand, Bodart et al., 2022), which used a 4 us linear frequency modulated pulse in addition to a standard short 0.25 us pulse Data are provided as XYZ ASCII line data.

Thwaites Glacier, West Antarctica. An animated time series plot of 64 profiles of ice base and surface elevation along a flowline based on the mean flow direction. The flowline passes through a region of large elevation change that took place between 2014 and 2017. The work was funded by NERC projects NE/P011365/1 and NE/S006605/1

A time series of surface elevation at a point on Thwaites Glacier, West Antarctica. The point is on grounded ice and is upstream of a sub-shelf cavity on the west flank of the fast-moving core of Thwaites Glacier. There are a total of 88 points. First column = yyyy-mm-dd, second column = elevation in metres. The work was funded by NERC projects NE/P011365/1 and NE/S006605/1.