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    This metadata record represents the first direct comparison of seismic and ultrasonic data with measured crystallographic preferred orientations Crystallographic preferred orientations (CPO) in a polar shear margin (Priestly Glacier, Antarctica). Analyses of seismic, ultrasonic and measured CPO datasets were combined to assess the potential of active-source seismic surveys for the constraint of shear margin anisotropy, which provide an assessment of ice flow dynamics and stability. A continuous ice core of 58 m length was drilled and recovered in December 2019 and January 2020 in a lateral shear margin of the Priestley Glacier, located in Victoria Land, Antarctica. Core samples were analysed for CPO using electron backscatter diffraction (EBSD) measurements. The core orientation was carefully preserved during drilling, which enabled azimuthal orientation of the CPO. To complete the link between seismic anisotropy of the ice volume around the borehole and CPO measurements from the core, multi-azimuthal ultrasonic velocity measurements were made on core samples in the laboratory. The vertical-seismic-profile (VSP) dataset was recorded at the Priestley drill site using a three-component borehole seismometer to investigate seismic properties and anisotropy within the glacier ice. Additionally, multi-azimuthal ultrasonic velocity measurements were conducted on core samples in the laboratory, complementing the seismic data analysis. Further details are provided at: Lutz, F., Prior, D.J., Still, H., Hamish Bowman, M., Boucinhas, B., Craw, L., Fan, S., Kim, D., Mulvaney, R., Thomas, R.E., & Hulbe, C.L. (2022). Ultrasonic and seismic constraints on crystallographic preferred orientations of the Priestley Glacier shear margin, Antarctica. *Cryosphere*, 16(8), 3313-3329. https://doi.org/10.5194/tc-16-3313-2022 GET DATA: https://auckland.figshare.com/articles/dataset/Priestley_Glacier_seismic_and_ultrasonic_constraints_on_crystallographic_orientation/17108639

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    This metadata record represents snow radar profiling for regional snow accumulation rate and radar echo profiling for tracing firn layers at Hot Water Drill Site 2 (HWD2). GET DATA: wolfgang.rack@canterbury.ac.nz

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    Here we examine the water stable-isotope data from the Roosevelt Island Climate Evolution (RICE) ice core. In this study, we use empirical orthogonal function (EOF) analysis to investigate the relationship between RICE ice-core oxygen-18 isotopes (δ18O) and Southern Hemisphere atmospheric circulation during the extended austral winter (April–November). - Deep Location: 79.364°S, 161.706°W, elevation 550 m a.s.l. - 12/13B Location: 79.362°S, 161.698°W, elevation 550 m a.s.l. - Core depth 763 m. Depth interval provided here: 1.29 to 38.56 m - txt data file, NaN = no data Further details are available at https://doi.org/10.1007/s00382-022-06568-8 GET DATA: https://github.com/demanuelsson/ClimDyn_2022_Matlab/tree/main/data

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    Ocean current speed and direction were recorded at 5-minute intervals at a nominal depth of 100 m in McMurdo Sound at 77.7667 °S, 165.2000 °E by an Aanderaa Seaguard single-point current meter. The dates covered by the ocean current observations are from 3-11-2017 06:35:02 UTC to 20-11-2017 22:55:02 UTC. Current speed is provided in units of cm/s. Current direction is provided in degree relative to true north and is the direction the current is flowing towards.

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    Acoustic volume backscatter measurements were made by an ASL Environmental Sciences Acoustic Zooplankton Fish Profiler (AZFP) operating at four-frequencies (125 kHz, 200 kHz, 455 kHz and 769 kHz). README: https://store.pangaea.de/Publications/Robinson-etal_2020/AZFP2016_README.pdf Further details are provided at: Frazer, E. K., Langhorne, P. J., Leonard, G. H., Robinson, N. J., & Schumayer, D. (2020). Observations of the size distribution of frazil ice in an Ice Shelf Water plume. Geophysical Research Letters, 47, e2020GL090498. https://doi.org/10.1029/2020GL090498

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    Acoustic volume backscatter measurements were made by an ASL Environmental Sciences Acoustic Zooplankton Fish Profiler (AZFP) operating at four-frequencies (125 kHz, 200 kHz, 455 kHz and 769 kHz). README: https://store.pangaea.de/Publications/Robinson-etal_2020/AZFP2017_README.pdf Further details are provided at: Frazer, E. K., Langhorne, P. J., Leonard, G. H., Robinson, N. J., & Schumayer, D. (2020). Observations of the size distribution of frazil ice in an Ice Shelf Water plume. Geophysical Research Letters, 47, e2020GL090498. https://doi.org/10.1029/2020GL090498

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    Ocean salinity was recorded at 10 second intervals by a Seabird Electronics SBE 37 microCAT CTD at a nominal depth of 100 m in McMurdo Sound at 77.6152 °S, 164.8821 °E. The dates covered by the salinity observations at 100 m depth are from 28-10-2016 06:43:11 UTC to 13-11-2016 21:59:51 UTC. The salinity is reported in units of practical salinity. Ocean temperature was recorded at 10 second intervals by a Seabird Electronics SBE 56 thermistor at a nominal depth of 75 m in McMurdo Sound at 77.6152 °S, 164.8821 °E. The dates covered by the temperature observations at 75 m depth are from 3-11-2017 08:26:01 UTC to 20-11-2017 23:00:01 UTC. The temperature is reported in units of °C in the ITS-90 temperature scale.

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    The data are approximately 800 km of airborne electromagnetic survey of coastal sea ice and sub-ice platelet layer (SIPL) thickness distributions in the western Ross Sea, Antarctica, from McMurdo Sound to Cape Adare. Data were collected between 8 and 13 November 2017, within 30 days of the maximum fast ice extent in this region. Approximately 700 km of the transect was over landfast sea ice that had been mechanically attached to the coast for at least 15 days. Most of the ice was first-year sea ice. Unsmoothed in-phase and quadrature components are presented at all locations. Data have been smoothed with an 100 point median filter, and in-phase and quadrature smoothed data are also presented at all locations. Beneath level ice it is possible to identify the thickness of an SIPL and a filter is described (Langhorne et al) to identify level ice. Level ice in-phase, quadrature and SIPL thickness, derived from these, are presented at locations of level ice. For rough ice, the in-phase component is considered the best measure of sea ice thickness. For level ice where there is the possibility of an SIPL, then the quadrature component is considered the best measure of ice thickness, along with SIPL thickness. All data are in meters.

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    These data are described in detail by 'Melting and refreezing in an ice shelf basal channel at the grounding line of the Kamb Ice Stream 1/ HWD1. ApRES observations were made in December 2019 and repeated in December 2020 at the same locations. Data collection and processing followed the method described in Stewart et al. (2019). ApRES dataset.zip' contains raw ApRES data and processed results from a spatial survey of basal mass balance - detailed in Sections 2.2.4 and 3.2.2 of: Whiteford, A., Horgan, H. J., Leong, W. J., & Forbes, M. (2022). Melting and refreezing in an ice shelf basal channel at the grounding line of the Kamb Ice Stream, West Antarctica. Journal of Geophysical Research: Earth Surface, 127, e2021JF006532. https://doi.org/10.1029/2021JF006532 GET DATA: https://doi.org/10.5281/zenodo.5574647

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    Geodetic GNSS (Global Navigation Satellite Systems) and GNSS-RR (GNSS reflectometry /refractometry) experiments sharing a common tower and power supply were installed at Kamb Ice Stream site 3 (-82.628074, -156.306129). GNSS logging was set at 30 second intervals and data were saved in. sbf format. Deployments were used to capture the motion of the ice stream and ice shelf with a particular focus on the grounding zone. Total stations will also be used to monitor ice motion and deformation. These data combined provide boundary conditions and reveal controlling processes (ice deformation and tidal processes). GET DATA: r.levy@gns.cri.nz