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    AntAir ICE is an air temperature dataset for terrestrial Antarctica, the ice shelves, and the seasonal sea ice around Antarctica in a 1km2 spatial grid resolution and a daily temporal resolution available from 2003-2021. AntAir ICE was produced by modelling air temperature from MODIS ice surface temperature and land surface temperature using linear models. In-situ measurements of air temperature from 117 Automatic Weather Stations were used as the response variable. Each day has a bricked spatial raster with two layers, saved as a GeoTIFF format and in the Antarctic Polar Stereographic projection (EPSG 3031). The first layer is the predicted near surface air temperature for that day in degree Celsius * 10 and the second layer is the number of available MODIS scenes for that day ranging from 0 to 4. Areas with cloud contamination or without sea ice are marked with no data. Files for each year (2003-2021) are compressed with a ZIP files for each quarter. Python 3.8 was used for conversion of the MODIS products from HDF files to raster and all data handling and processing was thereafter done in R version 4.0.0. All data processing and modelling procedures are available as R scripts on a public Github repository: https://github.com/evabendix/AntAir-ICE. Using this code it is possible to download new available MODIS LST and IST scenes and apply the model to continue the near-surface air temperature dataset. Related Publication: https://doi.org/10.1038/s41597-023-02720-z GET DATA: https://doi.org/10.1594/PANGAEA.954750

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    This metadata record represents the code and data used for the first application of WRF-Hydro/Glacier in the McMurdo Dry Valleys (Commonwealth Glacier), which as a fully distributed hydrological model has the capability to resolve the streams from the glaciers to the bare land that surround them. We applied a glacier and hydrology model in the McMurdo Dry Valleys (MDV) to model the start and duration of melt over a summer in this extreme polar desert. To do so, we found it necessary to prevent the drainage of melt into ice and optimize the albedo scheme. We show that simulating albedo (for the first time in the MDV) is critical to modelling the feedbacks of albedo, snowfall and melt in the region. This is a first step towards more complex spatial modelling of melt and streamflow. The Zenodo data includes output point data (*.csv) and namelist used in: Pletzer, T., Conway, J.P., Cullen, N.J., Eidhammer, T., & Katurji, M. (2024). The application and modification of WRF-Hydro/Glacier to a cold-based Antarctic glacier. *Hydrology and Earth System Sciences*, 28(3), 459-478. https://doi.org/10.5194/hess-28-459-2024 The modifications to the WRF-Hydro/Glacier model used in the paper can be found on GitHub: https://github.com/tpletzer/wrf_hydro_nwm_coldglacier GET DATA: https://doi.org/10.5281/zenodo.10565032

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    Altitude profile measurements of water vapour, ozone and aerosols using balloon packages flown through the troposphere into the stratosphere as part of the Ross Island GRUAN site activities. Maximum altitude recorded was 29 km. This project is a collaboration between the National Institute of Water and Atmospheric Research (NIWA) and NOAA. Timeline: - November 2022: 2 flights - February 2023: 1 flight - October 2023: 3 flights Data are held internally at NIWA and NOAA, and will be stored in the GRUAN database (https://www.gruan.org/data) GET_DATA: https://www.gruan.org/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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    The thicknesses of sea ice and sub-ice platelet layer were measured at regular intervals on fast ice in McMurdo Sound, Antarctica in November and December of 2011. Thirty-metre cross-profiles were established at each site, and snow depths were measured at 0.5 m intervals along the transect lines with a metal ruler. A mean snow depth for each site was derived from these 120 measurements. Freeboard, sea ice thickness and sub-ice platelet layer thickness were recorded at five locations at each site - at the central crossing point and at the end points of each transect. The mean of these was then calculated and taken as representative of the site. Ice thicknesses were measured by using a tape measure with a brass T-anchor attached at the zero mark. This was deployed vertically through the drill-hole and allowed to rotate to a horizontal alignment when exiting the bottom of the drill-hole at the ice-ocean interface. From this position the anchor is slowly pulled upwards until some resistance is met and the first measurement is taken. This resistance is taken to mark the sub-ice platelet layer/ocean interface. The tape measure is then pulled harder, forcing the bar to pass through the sub-ice platelet layer until it sits flush against the sea ice/sub-ice platelet layer interface where a second measurement is taken. Measurement sites were about 5 km apart.

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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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    Plot data Mc Nemar: To enable comparisons with the 1961 and 2004 survey results, the Lambert Conformal Conic projection from the 2004 survey was used to precisely georeference and trim the RGB image across a 1-m2 grid, generating a total of 3,458 1-m2 grid cells. For each grid cell moss, lichen, or algae/cyanobacteria cover was extracted as one of the four cover classes: Heavy (>40%), Patchy (10–40%), Scattered (less than 10%), and None (0%) for the survey years 1962, 2004 and 2018. Ground truthing: To test the overall accuracy of cover classifications and ensure consistency with 2004 survey methodologies, a ground-truthing approach was performed. Photographs were taken of individual cells along eight transects, running west to east across the plot at 0.5, 1.5, 15.5, 16.5, 28.5, 29.5, 116.5 and 117.5 m distance from the NW corner. Each grid cell could be identified individually with an x/y coordinate in the centre and was surrounded by a rectangular frame parallel to the outer edge of the plot. A total of 174 photographs were taken and archived with Antarctica New Zealand. For each photographed grid cell, the presence of each functional group of vegetation and their cover class was assessed visually. Orthomosaic image: Aerial images were obtained using a DJI Matrice 600 Pro hex-rotor remotely piloted aircraft system equipped with a Canon EOS 5Ds camera (image size: 8688×5792 pixels, focal length: 50 mm, pixel size: 4.14 μm) on November 28, 2018. The flight altitude was 30 m above ground level, and a total of 10 ground-control points were included to provide accurate geo-referencing. An orthomosaic photo and accompanying DEM was generated with the acquired aerial images using Agisoft PhotoScan (now known as Metashape by Agisoft LLC, https://www.agisoft.com/) RELATED PUBLICATION: https://doi.org/10.1029/2022EF002823 GET DATA: https://doi.org/10.7488/ds/3417

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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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    As part of the Scott Base Redevelopment Marine Monitoring Programme, the impact of Scott Base's activities on the local marine environment was assessed. Sampling took place at three sites around Hut Point Peninsula on the southern half of Ross Island during October – November 2019 to assess anthropogenic contamination. Two acoustic doppler current profilers (ADCP; Nortek Signature 500) were deployed, and set with a 2-minute sampling period in 1m vertical depth bins from the seabed to the underside of the ice. Instrument heads were kept ~0.5 m beneath the under-surface. ADCP data were downloaded, extracted from their raw formats, and averaged into 10-minute intervals. A magnetic declination of 141.09° E was applied to the measured current direction to correct the readings to reflect true north and a pressure offset was applied to standardise depths relative to ambient air pressure at the seawater surface. Information on habitats and benthic epifauna assemblage composition were collected using high resolution video across 2 25m transects at ~22m depth. Multiple overlapping passes were made across the seabed transects at ~0.5 m depth contours between ~20 – 26 m in order to create a 2D orthomosaic image of each site. Analysis of the diver-collected video was done using individual frames. The video along each transect was divided into 10 equal time segments and still frames were taken at random from the first, third, fifth, seventh and ninth segments. Eight video frames were analysed per transect (i.e., n=8 per transect and n=16 per site) by one individual to minimise observer bias. Sediment samples were collected by divers to determine contaminant concentrations and sediment characteristics (sediment particle size composition, organic matter content, organic carbon content and algal pigment content) at each site. Sponge species (Sphaerotylus antarcticus and Laternula elliptica) were collected for tissue contaminant analysis. Full description of methods is available at: https://doi.org/10.1007/s00300-023-03181-1 GET DATA: drew.lohrer@niwa.co.nz