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

Raw images (over approximately 20.000 unique images) collected during the Adelie Penguin Census across 30+ colonies since 1981 (see associated metadata resource for list full list of colonies). Photographs were taken using a black and white film camera from 1981 to 2004 (inclusive) and 2008. Images are available in .tif fomrat. Images are digital from 2005 onwards (except 2008). Raw images are available in cr2/cr3 formats, and processed images are available across tif and jpg formats. High resolution scanning was initiated in 2011 to scan all the negatives in the collection. There are approximately 10,000 negatives in the collection. Images are taken from helicopter at between 2000-2500 feet. All images collected during the 2324 season are georeferenced with latitude and longitude positions in decimal degrees (WGS 84). Camera Settings: ISO = 400 Shutter speed = greater than 1/1000 Focus = manual, pre-focus to 800m Lens = 135mm with UV filter Aperture/ Exposure = F8 (or up to F11) Image Size = Full size White Balance Setting = Daylight Captures per minute = ~80 GET DATA: m.meredyth-young@antarcticanz.govt.nz

Data provided here have been collected as part of the project "Measurements and Improved Parameterization of the Thermal Conductivity and Heat Flow through First-Year Sea Ice", OPP-0126007* and include measurements of temperature and various ice properties at selected sites in first-year and multiyear sea ice in McMurdo Sound, Antarctica in the years 2002-2004. Data from earlier installations of thermistor chains for measurements of ice temperature carried out by the New Zealand team have also been included. Data files are in Microsoft Excel format, with individual worksheets for specific cores or temperature data sets. Detailed information and comments on data sampling location etc. are provided in the files. Further information on data collection, results etc. can be found in the following publications: Backstrom, L. G. E., and H. Eicken 2007, submitted, Capacitance probe measurements of brine volume and bulk salinity in first-year sea ice, Cold Reg. Sci. Tech. Pringle, D. J., H. Eicken, H. J. Trodahl, and L. G. E. Backstrom 2007, submitted, Thermal conductivity of landfast Antarctic and Arctic sea ice, J. Geophys. Res. Trodahl, H. J., S. O. F. Wilkinson, M. J. McGuinness, and T. G. Haskell 2001, Thermal conductivity of sea ice; dependence on temperature and depth, Geophys. Res. Lett., 28, 1279-1282. Data are in Microsoft Excel format. Abbreviations: AH = Arrival Heights; CH = Camp Haskell (near Delbridge Islands); VUW = Victoria University Wellington; UAF = University Alaska Fairbanks. RELATED PUBLICATION: https://doi.org/10.1017/jog.2022.108 GET DATA: https://drive.google.com/drive/folders/1ooUH9dPvWT66afFC51Cb0JOHg66rn0sy

This metadata record presents observations of ice shelf anisotropy derived from borehole seismic data. Hot-water-drilled boreholes were created at two sites: Windless Bight (WB) near the grounding line on Ross Island and HWD-2 in the central Ross Ice Shelf. The boreholes housed seismometers frozen at various depths within the ice, enabling seismic observations of shear wave splitting (SWS) using active seismic sources. At Windless Blight, borehole seismometers were installed at depths of 40 and 190 meters within the ∼220 m thick ice shelf during the 2016/2017 Antarctic field season. Seismic shots were recorded with a 2,000 Hz sampling rate and a 2 s record length, triggered by striking plates. The site was revisited in December 2017 to validate sensor survivability and reproduce survey geometry for SWS analysis using multiazimuth shots. At HWD-2, eight seismometers were deployed at depths ranging from 80 to 325 meters inside the ∼370 m thick ice shelf during the 2017/2018 field season. A total of 747 shots at 53 different shot points were recorded, with clear observations of split shear waves in the data. The study contributes valuable seismic data and methodology for understanding ice shelf anisotropy, enhancing our knowledge of Antarctic ice dynamics and seismic behavior. Further details are provided at: Lutz, F., Eccles, J., Prior, D. J., Craw, L.,Fan, S., Hulbe, C., et al. (2020). Constraining ice shelf anisotropy using shear wave splitting measurements from active‐source borehole seismics.Journal of Geophysical Research: EarthSurface,125, e2020JF005707. https://doi.org/10.1029/2020JF005707 GET DATA: https://auckland.figshare.com/s/9f783802272b825d7ad7

In Antarctica, ice shelves such as the Ross Ice Shelf (RIS) fringe 75% of the coastline and cover over 1.5 million km2, creating distinct and largely unexplored marine environments. It is fundamental to characterize the communities under these shelves to understand their biogeochemical role and predict how they might respond to future ice-shelf collapse 1,2. While historical studies suggested the RIS harbors active microorganisms 3–5, nothing is known about the composition of these communities. In this study, we profiled the composition, function, and activities of microbial communities in three seawater samples (400, 550, 700 m depth) underlying the shelf interior. We combined rate measurements with multi-omics (i.e. single-cell genomics, metagenomics, metatranscriptomics, and metaproteomics). Overall, below-shelf waters harbour microbial communities of comparable abundance and diversity to deep pelagic waters. Based on the meta-omic data, the community is inferred to be sustained by dark carbon fixation using ammonia, nitrite, and sulfur compounds as electron donors. In turn, these chemolithoautotrophs are predicted to support the aerobic heterotrophic majority and various trophic interactions. Consistently, this study and previous activity measurements suggest that dark carbon fixation is sufficient to sustain prokaryotic heterotrophic production, making the waters below the RIS presumably the largest chemolithotrophic system in the global ocean. Further details are provided at https://doi.org/10.1038/s41467-021-27769-5 GET DATA: https://www.ebi.ac.uk/ena/browser/view/PRJEB35712 GET DATA: https://www.ncbi.nlm.nih.gov/bioproject/?term=PRJNA593264

Aerial reconnaissance and photography are used in the Ross Sea sector of Antarctica to determine the breeding locations of Adélie penguins and to count the numbers of nests occupied during the early incubation period. From 1981 to present (two-year embargo), all islands and sea coasts between 158°E and 175°E have been searched, and 11 previously unreported breeding colonies discovered. The aim is to census Adélie (Pygoscelis adeliae) populations to provide basic data against which future population levels can be compared in order to monitor environmental change of the Antarctic Ocean ecosystem, both natural and man-induced. GET DATA: https://datastore.landcareresearch.co.nz/en_AU/dataset/adelie-penguin-census-data

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

Cosmogenic surface exposure chronologies were used to quantitatively constrain past rates of ice thinning, and the absolute timing of ice discharge and thinning events. We sampled glacial erratics and bedrock from Byrd Glacier (LW1 Nunatak, LW2 Nunatak, Lonewolf Nuntataks, Tiger Nunatak, Mt. Tadpole). Samples were analysed for their exposure history, and all sites contained glacial erratics. In particular, the Lonewolf Nunataks sites, which is located along the margin of the East Antarctic Ice Sheet revealed a plethora of glacial cobbles. Details of laboratory procedures can be found in the related publication. RELATED PUBLICATION: https://doi.org/10.1002/esp.5701 GET DATA: https://version2.ice-d.org/antarctica/publication/1139/

This work was primarily funded by the NASA-funded RISE-UP: Ross Ice Shelf & Europa Underwater Probe (PI Britney E. Schmidt) project. Field work at the KIS-1 site during the 2019-2020 season was completed through international collaboration between NASA, NSF/USAP, and Antarctica New Zealand, funded by the Aotearoa New Zealand Antarctic Science Platform (ANTA1801) Antarctic Ice Dynamics Project (ASP02101), and the NZARI-funded Aotearoa New Zealand Ross Ice Shelf Programme, “Vulnerability of the Ross Ice Shelf in a Warming World” (grant no. 2014-11). The data contained in this directory are merged and calibrated data files from three missions conducted with ROV Icefin through a borehole drilled through Ross Ice Shelf at KIS1 (-82.78410, -155.26267), near the Kamb Ice Stream grounding zone. Missions were conducted in 2019 on December 16th, 18th, and 21st (UTC). For questions or assistance working with the data please contact Britney Schmidt (britneys@cornell.edu) and Justin Lawrence (jdl287@cornell.edu). Related Publication: https://doi.org/10.1038/s41561-023-01129-y GET DATA: https://doi.org/10.15784/601625

The data is generated through modelling simulations using the University of Victoria Earth system climate model. The modelling dataset presented here corresponds to the study entitled "Transient response of Southern Ocean ecosystems during Heinrich stadials". This dataset contains data files of the complete transient simulations (FW,FE and FWFE) and 40ka-control simulation mentioned in Table 1 and Table 2 of the manuscript. We first performed a control simulation 40ka-control integrating a total of 10000 years. We use only the last 200 years of this control simulation for our analysis. The data is generated through modelling simulations using the University of Victoria Earth system climate model. All the final data is in nc format, which can be easily read by Python/ferret or any other common data analysing software. RELATED PUBLICATION: Saini,H., Meissner,K.J., Menviel,L., & Kvale,K.(2024). Transient response of Southern Ocean ecosystems during Heinrich stadials. Paleoceanography and Paleoclimatology, 39, e2023PA004754. https://doi.org/10.1029/2023PA004754 GET DATA: https://doi.org/10.5061/dryad.k3j9kd5dt