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  • Microwave radiometer data at Halley Station, Antarctica, 2013-present

  • This dataset presents the input and output data from a set of sensitivity experiments to simulate the evolution of the Laurentide ice sheet in the Early Holocene (10-7 thousand years ago). These data are presented in the manuscript "Simulating the Early Holocene demise of the Laurentide Ice Sheet with BISICLES (public trunk revision 3298)". Simulating the demise of the Laurentide Ice Sheet covering the Hudson Bay in the early Holocene is important for understanding the role of accelerated changes in ice sheet topography and melt in the ''8.2 ka event'', a century long cooling of the Northern Hemisphere by several degrees. Freshwater released from the ice sheet through a surface mass balance instability (known as the saddle collapse) has been suggested as a major forcing for the 8.2 ka event, but the temporal evolution of this pulse has not been constrained. Dynamical ice loss and marine interactions could have significantly accelerated the ice sheet demise, but simulating such processes requires computationally expensive models that are difficult to configure and are often impractical for simulating past ice sheets. Here, we developed an ice sheet model setup for studying the Laurentide Ice Sheet''s Hudson Bay saddle collapse and the associated meltwater pulse in unprecedented detail using the BISICLES ice sheet model, an efficient marine ice sheet model of the latest generation, capable of refinement to kilometre-scale resolution and higher-order ice flow physics. The setup draws on previous efforts to model the deglaciation of the North American Ice Sheet for initialising the ice sheet temperature, recent ice sheet reconstructions for developing the topography of the region and ice sheet, and output from a general circulation model for a representation of the climatic forcing. The modelled deglaciation is in agreement with the reconstructed extent of the ice sheet and the associated meltwater pulse has realistic timing. Furthermore, the peak magnitude of the modelled meltwater equivalent (0.07-0.13 Sv) is compatible with geological estimates of freshwater discharge through the Hudson Strait. The results demonstrate that while improved representation of the glacial dynamics and marine interactions are key for correctly simulating the pattern of early Holocene ice sheet retreat, surface mass balance introduces by far the most uncertainty. The new model configuration presented here provides future opportunities to quantify the range of plausible amplitudes and durations of a Hudson Bay ice saddle collapse meltwater pulse and its role in forcing the 8.2 ka event. Ilkka Matero was funded by the Leeds-York Natural Environment Research Council (NERC) Spheres Doctoral Training Partnership (NE/L002574/1). The contribution from Ruza Ivanovic was partly supported by NERC grant NE/K008536/1. Lauren Gregoire is funded by a UKRI Future Leaders Fellowship (MR/S016961/1). The work made use of the N8 HPC facilities, which are provided and funded by the N8 consortium and EPSRC (EP/K000225/1) and co-ordinated by the Universities of Leeds and Manchester.

  • Three separate airborne radar surveys were flown during the austral summer of 2016/17 over the Filchner Ice Shelf and Halley Ice Shelf (West Antarctica), and over the outlet glacier flows of the English Coast (western Palmer Land, Antarctic Peninsula) during the Filchner Ice Shelf System (FISS) project. This project was a NERC-funded (grant reference number: NE/L013770/1) collaborative initiative between the British Antarctic Survey, the National Oceanography Centre, the Met Office Hadley Centre, University College London, the University of Exeter, Oxford University, and the Alfred Wenger Institute to investigate how the Filchner Ice Shelf might respond to a warmer world, and what the impact of sea-level rise could be by the middle of this century. The 2016/17 aerogeophysics surveys acquired a total of ~26,000 line km of aerogeophysical data. The FISS survey consisted of 17 survey flights totalling ~16,000 km of radar data over the Support Force, Recovery, Slessor, and Bailey ice streams of the Filchner Ice Shelf. The Halley Ice Shelf survey consisted of ~4,600 km spread over 5 flights and covering the area around the BAS Halley 6 station and the Brunt Ice Shelf. The English Coast survey consisted of ~5,000 km spread over 7 flights departing from the Sky Blu basecamp and linking several outlet glacier flows and the grounding line of the western Palmer Land, including the ENVISAT, CRYOSAT, GRACE, Landsat, Sentinel, ERS, Hall, Nikitin and Lidke ice streams. 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 processed line aeromagnetic data collected using the Scintrex cs3 caesium wing-tip magnetometers mounted in the BAS aerogeophysically equipped Twin Otter aircraft. Data are provided as XYZ ASCII line data.

  • Water column acoustic data collected in the Scotia Sea (from 2008-04-16 to 2008-04-17) during cruise JR186. Multi-frequency (38,120 and 200 kHz) acoustic data were collected using a Simrad EK60 echo sounder. The dataset comprises of calibrated and processed 38 kHz volume backscattering strength (Sv, dB re 1m-1). Data processing was undertaken using Echoview and Matlab. Processed netCDF data files are made available as part of the NERC Southern Ocean Network of Acoustics (SONA) and the EU MESOPP project.

  • This dataset contains bed and surface elevation picks derived from airborne radar collected in 2016/17 over the Filchner Ice Shelf and Halley Ice Shelf (West Antarctica) as part of the 5-year Filchner Ice Shelf System (FISS) project funded by NERC (grant reference number: NE/L013770/1) and awarded to the British Antarctic Survey with contribution from the National Oceanography Centre, the Met Office Hadley Centre, University College London, the University of Exeter, Oxford University, and the Alfred Wenger Institute. The aim of this project was to investigate how the Filchner Ice Shelf might respond to a warmer world, and what the impact of sea-level rise could be by the middle of this century. This collaborative initiative collected ~15,000 line-km of new aerogeophysical data using the 150MHz PASIN radar echo sounding system (Corr et al., 2007) deployed on a British Antarctic Survey (BAS) Twin Otter. The majority of flights were flown as part of FISS over the Support Force, Recovery, Slessor, and Bailey ice streams. Separate flights over Halley 6 research station and Brunt Ice Shelf were also collected as part of this season. The bed and surface elevation picks for the English Coast part of this season are available at: https://doi.org/10.5285/e07d62bf-d58c-4187-a019-59be998939cc.

  • UK Met Office UM (Unified Model) output for Larsen Ice Shelf, run at 4km resolution. Modelling was carried out to support the Orographic Flows and the Climate of the Antarctic Peninsula (OFCAP) project during the 2010-2011 field season.

  • The KRILLBASE-length frequency database comprises individual length measurements of 613487 Euphausia superba from 6470 scientific net hauls. Some of these individually-measured krill have additional information on their sex and maturity stage. Most of these E. superba are postlarvae, but some of the hauls include small (< 20 mm) krill which likely include furcilia larvae as well as juveniles. Much of these data were compiled at British Antarctic Survey in 2007 by Mark Jessopp, with additional compilation by Angus Atkinson, Catherine Brewster and Natalie Ensor, and later data checking by Angus Atkinson with Helen Peat. The circumpolar distribution of records is illustrated in the file KRILLBASE_LF_DISTRIBUTION that is available along with this dataset. Examples of uses of KRILLBASE-length frequency are in Atkinson et al. (2009), Tarling et al. (2016), Perry et al. (2019) and Atkinson et al. (2019). The KRILLBASE-length frequency records were provided by contributing authors of the database or transcribed from the literature or from other institutional databases. At the time of data compilation, data from commercial-size large mesh trawls and from the commercial fishery was also transcribed, providing valuable information on the larger krill caught by these nets. These data are not included in this current KRILLBASE-length frequency database version, because of the difficulty in comparing them with the finer mesh scientific nets compiled here, and because length and population structure are also available in more complete form from CCAMLR. The KRILLBASE-length frequency database forms a complementary database to the KRILLBASE-abundance database (doi:10.5285/8b00a915-94e3-4a04-a903-dd4956346439), which compiles the abundance of Euphausia superba and salps in the Southern Ocean (Atkinson et al 2017). Both databases are multi-national, circumpolar compilations of net samples spanning years 1926 to 2016. The KRILLBASE-length frequency database uses some of the stations as KRILLBASE-abundance but also additional ones from targeted hauls or horizontal hauls.

  • This dataset contains bed and surface elevation picks derived from airborne radar collected in 2015/16 over Foundation Ice Stream and Filchner Ice Shelf as part of the 5-year Filchner Ice Shelf System (FISS) project funded by NERC (grant reference number: NE/L013770/1) and awarded to the British Antarctic Survey with contribution from the National Oceanography Centre, the Met Office Hadley Centre, University College London, the University of Exeter, Oxford University, and the Alfred Wenger Institute. The aim of this project was to investigate how the Filchner Ice Shelf might respond to a warmer world, and what the impact of sea-level rise could be by the middle of this century. This collaborative initiative collected ~7,000 line-km of new aerogeophysical data using the 150MHz PASIN radar echo sounding system (Corr et al., 2007) deployed on a British Antarctic Survey (BAS) Twin Otter.

  • Biological tissue samples from octopus species collected from the Southern Ocean, James Clark Ross cruise no. JR147/145. A large collection of tissue samples from deep sea and Antarctic target groups had already been collected in previous cruises. The specific objective of this cruise was to target three species of octopus, Pareledone charcoti (peak abundance 100m depth), Pareledone turqueti (peak abundance 100-200m) and Adelieledone polymorpha (peak abundance 250-350m), for the micro-evolution (i.e. population genetics) component of the project. Most of the octopuses were captured with an otter trawl, due to its relatively large sampling area and the fact that it can be trawled quickly (4 knots) which prevents octopuses from swimming out of it.

  • Input and results files for the ice dynamics model Ua simulating potential past and future ice geometry of Cook Glacier, East Antarctica. Results seek to explain potential causes of recent observed acceleration and speculate on future causes of acceleration. This work was funded by NERC grant NE/R000719/1.