This archive is a suite of ground penetrating radar (GPR) data acquired by Project MIDAS during field campaigns on Larsen C, in 2014 and 2015. All data were acquired with a Sensors&Software pulsEKKO PRO GPR system, fitted with antennas of 200 MHz centre-frequency. The system was towed behind a snowmobile, with distances recorded with GPS. These data are part of the NERC-funded MIDAS (''Impact of surface melt and ponding on ice shelf dynamics and stability'') research project, with grant references NE/L006707/1 and NE/L005409/1. Other MIDAS data are available.

Firstly, simulations of surface pressure, 10 m zonal wind speed, 10 m meridional wind speed, 1.5 m air temperature, and 1.5 m specific humidity over the Larsen C Ice Shelf for the duration of the OFCAP (Orographic Flows and the Climate of the Antarctic Peninsula) field campaign from 8 January 2011 to 8 February 2011 were conducted using the regional atmosphere-only configuration of the Met Office Unified Model (MetUM) at 4 km grid spacing by the British Antarctic Survey, Cambridge, UK. The datasets produced were necessary to compare with corresponding measurements derived from five Automatic Weather Stations (AWSs) distributed across the Larsen C Ice Shelf to evaluate the main biases in the simulations. Secondly, further MetUM simulations at grid spacings of 1.5 and 0.5 km of a foehn wind event that occurred on 27 January 2011 were conducted, with the datasets produced used to compare results at 4, 1.5 and 0.5 km grid spacing and examine whether the added benefit of sub-kilometre scale grid spacing improves the model representation of foehn winds. Thirdly, a simulation of the foehn wind event on 27 January 2011 using the MetUM at 4 km grid spacing but replacing the ''sharp'' stability function used by the boundary layer scheme with the ''long-tail'' stability function were also conducted, with the dataset produced used to examine the impact of stronger turbulent mixing for statically stable conditions on the model representation of foehn winds. Funding was provided by NERC grant NE/G014124/1.

The data consists of 30 minute observations recorded by an automatic weather station (iWS 18) in Cabinet Inlet on Larsen C Ice Shelf on the Antarctic Peninsula. The iWS consists of a custom-built weather station unit, assembled at the Institute of Marine and Atmospheric research Utrecht (IMAU). There are sensors for air temperature, surface air pressure, relative humidity, as well as a GPS, an acoustic snow height sensor, an ARGOS communication antenna, and three Lithium batteries that fuel the unit when solar radiation is absent. The unit is complemented by a propeller-vane Young anemometer measuring wind direction and speed. Additionally, all radiation fluxes are measured with a Kipp and Zonen CNR4 radiometer. This dataset runs from 25 November 2014 to 13 November 2017. Funding was provided by the NERC grant NE/L005409/1.

The datasets are temperature time series from thermistor strings installed into two boreholes drilled to a depth of ~7 m in the northern sector of Larsen C Ice Shelf, Antarctica. Supporting borehole information is presented by Ashmore and others (2017). These data are part of the NERC-funded MIDAS (''Impact of surface melt and ponding on ice shelf dynamics and stability'') research project, with grant references NE/L006707/1 and NE/L005409/1. Associated (longer) borehole temperature records, OPTV logs and density records are also available, as are other MIDAS datasets.

The data consists of 30 minute observations recorded by an automatic weather station (iWS 18) in Cabinet Inlet on Larsen C Ice Shelf on the Antarctic Peninsula. The iWS consists of a custom-built weather station unit, assembled at the Institute of Marine and Atmospheric research Utrecht (IMAU). There are sensors for air temperature, surface air pressure, relative humidity, as well as a gps, an acoustic snow height sensor, an ARGOS communication antenna, and three Lithium batteries that fuel the unit when solar radiation is absent. The unit is complemented by a propeller-vane Young anemometer measuring wind direction and speed. Additionally, all radiation fluxes are measured with a Kipp and Zonen CNR4 radiometer. This dataset runs from November 2014 to January 2017. Funded was provided by the NERC grant NE/L005409/1. ***** PLEASE BE ADVISED TO USE VERSION 2.0 DATA ***** The VERSION 2.0 data set (see ''Related Data Set Metadata'' link below) has an additional 10 months of measurements.

This dataset contains output from a hydrodynamic model of the ocean in the Larsen C Ice Shelf (LCIS) cavity and a nearby area of the western Wedell Sea. Simulations were run using the MITgcm numerical ocean model and included an ice shelf with steady thickness. A new LCIS bathymetry was used in the simulations, referred to as the ''Brisbourne'' bathymetry. The data provided here includes these geometry grids and ocean velocity and basal melt rate fields output from the final year of an arbitrary 10-year simulation, or a 6-month extension run. Calculated marine ice fields beneath the ice shelf based on the simulation''s melt rate results are also included. In addition, output from several simulations using different initial and boundary ocean temperature conditions and runs with different cavity geometries are also provided. This work was supported by the Natural Environment Research Council and the EnvEast Doctoral Training Partnership [grant number NE/L002582/1] and PICCOLO [grant number NE/P021395/1].

These are vertical density profiles of snow, firn and ice reconstructed from the vertical luminosity trace of digital optical televiewer (OPTV) logs of five boreholes drilled by hot water to ~100 m depth in Larsen C Ice Shelf, Antarctica. Boreholes were drilled in austral summers of 2014 and 2015 in order to investigate the internal properties of the ice shelf, and specifically the influence of surface melting and melt pond formation on those properties. These data are part of the NERC-funded MIDAS (''Impact of surface melt and ponding on ice shelf dynamics and stability'') research project, with grant references NE/L006707/1 and NE/L005409/1. The associated borehole OPTV logs and temperature profiles are also available, as are other MIDAS datasets.

Seismic refraction experiments were conducted in four locations in the Whirlwind Inlet, Larsen C Ice Shelf, with the main purpose of estimating firn density profiles. The data were collected as part of NERC Project MIDAS. The locations, procedures and raw data files produced along with quality descriptions are all summarised in the observer''s log provided along with the datasets. Funding was provided by NERC Standard Grant ''Impact of surface melt and ponding on ice shelf dynamics and stability'', 2014-2017, NERC Reference NE/L005409/1.

The datasets are temperature time series from strings of thermistors, each located at a discrete depth within one of six boreholes drilled to a depth of ~100 m in the northern sector of Larsen C Ice Shelf, Antarctica. Supporting borehole information is presented by Ashmore and others (2017). These data are part of the NERC-funded MIDAS (''Impact of surface melt and ponding on ice shelf dynamics and stability'') research project, with grant references NE/L006707/1 and NE/L005409/1. Associated (near-surface) borehole temperature records, OPTV logs and density records are also available, as are other MIDAS datasets.

In 2016, a series of ice shelf cavity bathymetry point measurements were made across Larsen C Ice Shelf, West Antarctica. The sites were selected to address deficiencies in the coverage provided by existing data sets. A hammer and plate seismic source was used. Seismic reflection data were recorded on 24 receivers at 10 m interval and 30 m offset. Sea bed reflections are observed at all sites. Surface elevation measurements are provided to allow estimation of ice thickness when an ice base reflection is not visible. Funded as part of the Polar Science for Planet Earth Programme, British Antarctic Survey, Natural Environment Research Council.