Surface snow samples were collected daily from a Canadian high Arctic location at Eureka, Nunavut (80N, 86W) from the end of February to the end of March in 2018 and 2019. The snow samples were collected at several sites representing distinct environments: sea ice, inland close to sea level, and a hilltop ~600 m above sea level. Ion Chromatography (IC) analysis was performed for most of the snow samples. Snow salinity measurement is mainly for surface snow. Surface ozone was measured at sea level (from the Zero Altitude PEARL Auxiliary Laboratory (0PAL)) and lower tropospheric BrO (0-4 km) was measured by MAX-DOAS instrument (at ~610 m located at the Polar Environment Atmospheric Research Laboratory (PEARL)). This study was supported by the UK NERC Arctic office via two UK-Canada bursary programs: "The role of tundra snowpack chemistry in the boundary layer bromine budget at Eureka, Canada" (2018), and "A second investigation of the role of tundra snowpack chemistry in the boundary layer ''bromine explosion''" (2019). The Eureka MAX-DOAS BrO measurements made at the PEARL Ridge Laboratory by the Canadian Network for the Detection of Atmospheric Change (CANDAC) was primarily supported by the Natural Sciences and Engineering Research Council of Canada (NSERC), the Canadian Space Agency (CSA), and Environment and Climate Change Canada (ECCC).

This dataset provides a geopackage of the predicted subglacial water flow pathways beneath Whillans Ice Plain, West Antarctica, the contributory Whillans Ice Stream and neighbouring Kamb and Mercer Ice Streams. Flow paths were estimated based on hydropotential gradients using static grids of ice-surface elevation from the REMA mosaic (Howat and others, 2019) and ice thickness from Bedmachine Antarctica version 3 (Morlighem and others, 2020; 2022) from which bed elevation is inferred. Wilson Sauthoff (dataset creator) was funded by NASA award 80NSSC21K0912. 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).

This dataset contains the position and depth (ice thickness) of three spatially-extensive Internal Reflecting Horizons (IRHs) mapped from ice-penetrating radar data acquired with the British Antarctic Survey''s PASIN and PASIN2 ice radar systems across central East Antarctica. The dataset extends geographically from Dome A to South Pole. Using previous dated IRHs from Winter et al (2019), an independent validation of IRH ages from the South Pole ice-core chronology and a 1-D steady-state model, we assigned ages to our three IRHs: (H1) 38.5 +/- 2.2 ka, (H2) 90.4 +/- 3.57, and (H3) 161.9 +/- 6.76 ka. This study was motivated by the AntArchitecture Action Group of the Scientific Committee for Antarctic Research (SCAR). The project was supported by the National Environmental Research Council (NERC)-funded ONE Planet Doctoral Training Partnership (NE/S007512/1), hosted jointly by Newcastle and Northumbria Universities. The authors thank the BAS science and logistics teams for acquiring both the AGAP PASIN and PolarGAP PASIN2 data which is fully available on the Polar Airborne Geophysics Data Portal of the UK Polar Data Center (https://www.bas.ac.uk/project/nagdp/). BedMachine (version 2) data are available at https://doi.org/10.5067/E1QL9HFQ7A8M.

Incoming irradiance at the surface and transmitted through snow and sea ice was measured during a cruise to the Chukchi Sea in August 2019 with the Korean RV Araon using TriOS RAMSES planar radiometers. The data was collected to improve understanding of how the physical and optical properties of various sea ice conditions affect the solar partitioning by snow and sea ice in the Arctic Ocean and how this might affect the ecosystem trophic levels relying on photosynthesis. The data is also used to improve parameterisation in models or for remote sensing applications in order to upscale to a pan-Arctic level. This dataset resulted from the NERC project (NE/R012725/1) Eco-Light, part of the Changing Arctic Ocean programme, jointly funded by the UKRI Natural Environment Research Council (NERC) and the German Federal Ministry of Education and Research (BMBF).

This dataset is a sequential list of all the terrestrial snow and ice samples taken at Robert Island, Antarctica from January 2023 to March 2023. Sample date, location, bloom colour and what the sample was subsequently used for (metabolomics, pigment, DNA, DOC, FTIR, CN), along with cell counts is provided. Cell counts and biometric measurements of Ancylonema are included in the dataset. The samples were taken by small 15ml or 50ml plastic tube sampling in the snow pack or on the icecap hard ice. This was to study the habitat and ecosystem progression over the season and linking this to other satellite or drone or vegetation data. A remote sensing output (red snow algae vector for Robert Island) was also produced. The expedition and sampling was carried out by Matthew Davey (PI), Alex Thomson, Andrew Gray, Hannah Moulton, Charlotte Walshaw with support from INACH, Chile and BAS. This was part of a wider project with Claudia Colesie, Naomi Thomas, Peter Convey, Alison G. Smith, Peter Fretwell, Lloyd Peck. Samples were transferred to UK (SAMS) for further analysis. This project was funded by Standard NERC References: NE/V000764/1 and NE/V000896/1. The past, present and future of snow algae in Antarctica: a threatened terrestrial ecosystem?

Measurements of mean annual temperature in degrees Celsius at 22 sites in Pine Island Glacier, located by hand held Garmin GPS position, and altitude recorded by survey quality Leica GPS. The mean annual temperature of a remote ice sheet site is generally agreed to be equivalent to the temperature measured at 10m depth in a borehole. This dataset records the 10m temperatures at 22 remote sites in the Pine Island Glacier region of the West Antarctic Ice Sheet. Data were recorded on a single thermistor logging thermometer for a period of 12 to 24 hours on the date noted in table (marked in table as ''Single thermistor'') or as the mean of two cables with parallel triple thermistors measured at a single time (date/time noted in table) after a minimum of 12 hours settling in the borehole (marked in table as ''Average of six thermistors''). Measurements were made independently in two boreholes: one drilled to approximately 12m for deployment of a neutron source ice density probe (marked in table as ''10m temperature neutron probe borehole''); one drilled to approximately 50m during recovery of an ice core (marked in table as ''10m temperature ice core borehole''). Some have argued that the mean annual temperature is better measured at 15m in a borehole to remove any trace of the seasonal surface temperature cycle. In the table we additionally record the temperature in the ice core borehole at 15m (marked in table as ''15m temperature ice core borehole'') using a logging PT-100 temperature device (marked in table as ''Single PT-100'').

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).