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    This metadata record represents meteorological data and in situ and isotopic measurements of the isotopic ratio of water vapor from the ablating ice from two lakes in the McMurdo Dry Valleys, Antarctica. Lake ice and water samples (from the surface water and at depth via SCUBA) were collected in vials. Ice samples at Lake Bonney were collected daily, and at Lake Fryxell samples were collected approximately twice per day. Lake ice samples were also collected at Lake Fryxell along three transects spaced approximately every 300 to 500 m (meters) across the lake surface. Water vapor isotope flux measurements were collected via air inlets which were installed at 0.5, 1.0, and 3.0 m on the tower using ¼″ OD Teflon tubes. The lines were insulated and continuously pumped at a flow rate of approximately 10 L min−1 using a secondary pump. Meteorological measurements with a Vaisala HMP100 probe for temperature and relative humidity readings and an RM Young wind vane (model 05108) for wind velocity measurements, at heights of 3.0 and 0.5 m. Air temperature, relative humidity, wind velocity, and lake surface temperature measurements were recorded every minute via a Campbell Scientific CR1000 data logger. Spatial Coordinates: Lake Bonney (-77.60672778, 162.44982222) Lake Fryxell (-77.60672778, 163.12508611) Further details are provided at: A. W. Bellagamba, M. Berkelhammer, L. Winslow, P. T. Doran, K. F. Myers, S. Devlin & I. Hawes (2021) The magnitude and climate sensitivity of isotopic fractionation from ablation of Antarctic Dry Valley lakes, Arctic, Antarctic, and Alpine Research, 53:1, 352-371, https://doi.org/10.1080/15230430.2021.2001899 GET DATA: https://uofi.app.box.com/s/6vakvltbsn1nhrpzudffclrn5iufpoux/folder/88268262341

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    This dataset contains 5 s average phase and amplitude data from VLF radio wave communication transmitters received on two subionospheric propagation paths. The first is the path from NPM (Hawaii, 21.4 kHz, 21.4⁰N, 158.2⁰E), recorded at the field-site for New Zealand's Scott Base, Arrival Heights, in Antarctica (77.8⁰S, 166.8⁰E). The propagation path is ~11 Mm long, oriented nearly north-south, with the mid-point at 28.9⁰S, 164.4⁰W. The second is from NAA (Culter, Maine, USA, 24.0 kHz, 44.7⁰N, 67.3⁰E), and recorded at Sodankylä Geophysical Observatory (Lapland, Finland, 67.4⁰N, 26.4⁰E). The propagation path is ~6 Mm. Both VLF recievers are UltraMSK software defined radio systems connected to magnetic field sensing loops. The data files are formatted as ASCII text files with columns of time (s), amplitude (dB) & phase (degrees) data. The MATLAB script plotUltraMSK.m can be used to plot the data files and an example data plot has been included in the dataset. Further details provided at: Belcher, S. R. G., Clilverd, M. A., Rodger, C. J., Cook, S., Thomson, N. R., Brundell, J. B., & Raita, T. (2021). Solar flare X-ray impacts on long subionospheric VLF paths. Space Weather, 19, e2021SW002820. https://doi.org/10.1029/2021SW002820 GET DATA: https://doi.org/10.5281/zenodo.4774464

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    Data of apparent ice thickness from airborne electromagnetic (AEM) surveys of fast ice in McMurdo Sound, Antarctica, carried out in Nov/Dec 2009, 2011, 2013, 2016, and 2017. Values are given for apparent thicknesses derived from both, in-phase and quadrature signals. The difference between both thicknesses is a scaled measure of sub-ice platelet layer thickness. Data are from east-west transects across McMurdo Sound, at fixed latitudes. Data were smoothed and interpolated onto a regular longitude grid (0.001 degree increments). More information can be found in Haas et al. (2021). Related Publication: Haas, C., Langhorne, P. J., Rack, W., Leonard, G. H., Brett, G. M., Price, D., Beckers, J. F., and Gough, A. J.: Airborne mapping of the sub-ice platelet layer under fast ice in McMurdo Sound, Antarctica, The Cryosphere, 15, 247–264, https://doi.org/10.5194/tc-15-247-2021, 2021

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    Sea ice thickness and sub-ice platelet layer thickness under fast ice were measured at regular intervals at two North-South oriented profiles and four east-west oriented profiles in McMurdo Sound, Antarctica in November 2013. Holes were drilled at regular intervals into sea ice at measurement sites about 10 km apart. The thickness was measured using measurement tapes. Snow depth on sea ice was also measured at all sites

  • The structural glaciology and movement of the Taylor Glacier, was investigated over several seasons (98-01) by excavating a tunnel in the right side of the Taylor Glacier, 1.5km upstream of the terminus, to provide access to basal ice and the glacier substrate. Basal ice was sampled and analysed for concentration of base cations and chlorides present. Strain arrays and precision dial gauges were installed to monitor movement and deformation of the tunnel and ice velocity. In situ samples of clean and debris bearing glacier ice shear samples were taken from the basal ice to test in a laboratory. The tunnel was re-cut 1.3km upstream of the terminus in the 99-00 season as the other had closed in, with strain arrays and plumb lines installed and basal ice re-sampled. Ice cores were sampled for mechanical tests from the tunnel and the glacier surface. Ice cores were taken from the ice margin of Lake Bonny. Strain arrays and plumb lines were resurveyed and the deformation of the tunnel measured. This metadata record represents: - Data set from Taylor Glacier tunnel - Photographs of tunnel excavation - Video of tunnel excavation Further details are provided at: Fitzsimons, S., Samyn, D., & Lorrain, R (2024). Deformation, strength and tectonic evolution of basal ice in Taylor Glacier, Antarctica. Journal of Geophysical Research: Earth Surface, 129, e2023JF007456. https://doi.org/10.1029/2023JF007456 GET DATA: https://doi.org/10.5281/zenodo.8232003

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    The major histocompatibility complex (MHC) is a highly polymorphic gene family that is crucial in immunity, and its diversity can be effectively used as a fitness marker for populations. Despite this, MHC remains poorly characterised in non-model species (e.g., cetaceans: whales, dolphins and porpoises) as high gene copy number variation, especially in the fast-evolving class I region, makes analyses of genomic sequences difficult. To date, only small sections of class I and IIa genes have been used to assess functional diversity in cetacean populations. Here, we undertook a systematic characterisation of the MHC class I and IIa regions in available cetacean genomes. We extracted full-length gene sequences to design pan-cetacean primers that amplified the complete exon2 from MHC class I and IIa genes in one combined sequencing panel. We validated this panel in 19 cetacean species and described 354 alleles for both classes. Furthermore, we identified likely assembly artefacts for many MHC class I assemblies based on the presence of class I genes in the amplicon data compared to missing genes from genomes. Finally, we investigated MHC diversity using the panel in 25 humpback and 30 southern right whales, including four paternity trios for humpback whales. This revealed copy-number variable class I haplotypes in humpback whales, which is likely a common phenomenon across cetaceans. These MHC alleles will form the basis for a cetacean branch of the Immuno-Polymorphism Database (IPD-MHC), a curated resource intended to aid in the systematic compilation of MHC alleles across several species, to support conservation initiatives. The dataset contains 85 fastq files. Each file contains reads of amplicons from five MHC loci (DQA, DQB, DRA, DRB, and class I genes) combined across separate sequencing runs from a single cetacean. Details on individual cetacean sample abbreviations can be found in the manuscript. Reads are paired and merged with the Illumina adapter removed. It also contains one fastq file with all class I alleles found and one fastq file with non-functional DRB alleles found. Alleles are labeled with four letter species abbreviation followed by locus designation (DRB or N for class I) and are numbered in the order they were discovered. Further details are provided at: Heimeier, D., Garland, E. C., Eichenberger, F., Garrigue, C., Vella, A., Baker, C. S., & Carroll, E. L. (2024). A pan-cetacean MHC amplicon sequencing panel developed and evaluated in combination with genome assemblies. Molecular Ecology Resources, 00, e13955. https://doi.org/10.1111/1755-0998.13955 GET DATA: https://doi.org/10.5061/dryad.wh70rxwvb

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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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    These data were aquired with a Terrestrial Radar Interferometer overlooking the grounding zone of Priestley Glacier, Antarctica. The time series contains differential interferograms with a 12h temporal baseline covering an approximately 8 day period in November 2018. Tidal modulation of ice streams and their adjacent ice shelves is a real-world experiment to understand ice-dynamic processes. We observe the dynamics of Priestley Glacier, Antarctica, using Terrestrial Radar Interferometry (TRI) and GNSS. Ocean tides are predominantly diurnal but horizontal GNSS displacements oscillate also semi-diurnally. The oscillations are strongest in the ice shelf and tidal signatures decay near-linearly in the TRI data over >10 km upstream of the grounding line. Tidal flexing is observed >6 km upstream of the grounding line including cm-scale uplift. Tidal grounding line migration is small and <40 % of the ice thickness. The frequency doubling of horizontal displacements relative to the ocean tides is consistent with variable ice-shelf buttressing demonstrated with a visco-elastic Maxwell model. Taken together, this supports previously hypothesized flexural ice softening in the grounding-zone through tides and offers new observational constraints for the role of ice rheology in ice-shelf buttressing. Related Publication: Drews, R., Wild, C. T., Marsh, O. J., Rack, W., Ehlers, T. A., Neckel, N., & Helm, V. (2021). Grounding-zone flow variability of Priestley Glacier, Antarctica, in a diurnal tidal regime. Geophysical Research Letters, 48, e2021GL093853. https://doi.org/10.1029/2021GL093853 GET DATA: https://doi.org/10.1594/PANGAEA.935707

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    Microsatellites are widely used in population genetics, but their evolutionary dynamics remain poorly understood. It is unclear whether microsatellite loci drift in length over time. This is important because the mutation processes that underlie these important genetic markers are central to the evolutionary models that employ microsatellites. We identify more than 27 million microsatellites using a novel and unique dataset of modern and ancient Adélie penguin genomes along with data from 63 published chordate genomes. We investigate microsatellite evolutionary dynamics over two time scales: one based on Adélie penguin samples dating to approximately 46.5 kya, the other dating to the diversification of chordates more than 500 Mya. We show that the process of microsatellite allele length evolution is at dynamic equilibrium; while there is length polymorphism among individuals, the length distribution for a given locus remains stable. Many microsatellites persist over very long time scales, particularly in exons and regulatory sequences. These often retain length variability, suggesting that they may play a role in maintaining phenotypic variation within populations. Further details are provided at: Bennet J McComish, Michael A Charleston, Matthew Parks, Carlo Baroni, Maria Cristina Salvatore, Ruiqiang Li, Guojie Zhang, Craig D Millar, Barbara R Holland, David M Lambert, Ancient and Modern Genomes Reveal Microsatellites Maintain a Dynamic Equilibrium Through Deep Time, Genome Biology and Evolution, Volume 16, Issue 3, March 2024, evae017, https://doi.org/10.1093/gbe/evae017 GET DATA: https://doi.org/10.5061/dryad.7gt3rg2

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    These data were aquired with a Terrestrial Radar Interferometer overlooking the grounding zone of Priestley Glacier, Antarctica. The time series contains differential interferograms with a 12h temporal baseline covering an approximately 8 day period in November 2018. Tidal modulation of ice streams and their adjacent ice shelves is a real-world experiment to understand ice-dynamic processes. We observe the dynamics of Priestley Glacier, Antarctica, using Terrestrial Radar Interferometry (TRI) and GNSS. Ocean tides are predominantly diurnal but horizontal GNSS displacements oscillate also semi-diurnally. The oscillations are strongest in the ice shelf and tidal signatures decay near-linearly in the TRI data over >10 km upstream of the grounding line. Tidal flexing is observed >6 km upstream of the grounding line including cm-scale uplift. Tidal grounding line migration is small and <40 % of the ice thickness. The frequency doubling of horizontal displacements relative to the ocean tides is consistent with variable ice-shelf buttressing demonstrated with a visco-elastic Maxwell model. Taken together, this supports previously hypothesized flexural ice softening in the grounding-zone through tides and offers new observational constraints for the role of ice rheology in ice-shelf buttressing. Time series of line-of-sight flowfields averaged over approximately three hours. Data were taken with a Terrestrial Radar Interferometer in November 2018 at the grounding zone of Priestley Glacier, Antarctica – The Zip Archive contains 288 Geotiff in South polar stereographic projection – Each raster has 4027 x 4746 entries – The file name details the approximately 3h time inverval of aquisition with Stack_YYYYMMDD_HHMMSS_YYYYMMDD_HHMMSS marking the beginning and end of the time interval, respectively. – The line of sight velocities are given in meters per year Related Publication: Drews, R., Wild, C. T., Marsh, O. J., Rack, W., Ehlers, T. A., Neckel, N., & Helm, V. (2021). Grounding-zone flow variability of Priestley Glacier, Antarctica, in a diurnal tidal regime. Geophysical Research Letters, 48, e2021GL093853. https://doi.org/10.1029/2021GL093853 GET DATA: https://doi.org/10.1594/PANGAEA.935702