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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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    Radiolarians (holoplanktonic Protozoa) found in marine sediments are commonly used in Southern Ocean as palaeoclimate proxies. Generating such reconstructions of past climate based on radiolarian abundances requires a spatially and environmentally comprehensive reference dataset of modern radiolarian census counts. The Southern Ocean RADiolarian (SO-RAD) dataset includes census counts for 237 radiolarian taxa from 228 surface sediment samples located in the Atlantic, Indian and South-west Pacific sectors of the Southern Ocean. This compilation is the largest radiolarian census dataset derived from surface sediment samples in the Southern Ocean. The SO-RAD dataset may be used as a reference dataset for palaeoceanographic reconstructions, or for studying modern radiolarian biogeography and species diversity. RELATED PUBLICATION: https://doi.org/10.5194/essd-13-5441-2021

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    This metadata record represents the R phytoclass package. Determine the chlorophyll a (Chl a) biomass of different phytoplankton groups based on their pigment biomarkers. The method uses non-negative matrix factorisation and simulated annealing to minimise error between the observed and estimated values of pigment concentrations (Hayward et al. (2023) https://doi.org/10.1002/lom3.10541). The approach is similar to the widely used 'CHEMTAX' program (Mackey et al. 1996) https://doi.org/10.3354/meps144265), but is more straightforward, accurate, and not reliant on initial guesses for the pigment to Chl a ratios for each phytoplankton group. Further details are provided at: Hayward, A., M. H. Pinkerton, and A. Gutierrez-Rodriguez. 2023. phytoclass: A pigment-based chemotaxonomic method to determine the biomass of phytoplankton classes. Limnol. Oceanogr. Methods 21: 220–241. https://doi.org/10.1002/lom3.10541 GET PACKAGE: https://cran.r-project.org/web/packages/phytoclass/readme/README.html

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    This metadata record represents the data from 15 passive seismic stations at Kamb Ice Stream (site 2). Seismic stations measure vibrations in the ice providing boundary conditions and revealing controlling processes (ice-substrate interaction). Seismometers were deployment within 50 km radius of KIS2 borehole (subglacial channel). GET DATA: r.levy@gns.cri.nz

  • GET DATA: https://doi.org/10.5281/zenodo.3940766 This archive provides the ice sheet model outputs produced as part of the publication "ISMIP6 Antarctica: a multi-model ensemble of the Antarctic ice sheet evolution over the 21st century", published in The Cryosphere, https://tc.copernicus.org/articles/14/3033/2020/ Contact: Helene Seroussi, Helene.seroussi@jpl.nasa.gov Further information on ISMIP6 and ISMIP6 Antarctica Projections can be found here: http://www.climate-cryosphere.org/activities/targeted/ismip6 http://www.climate-cryosphere.org/wiki/index.php?title=ISMIP6-Projections-Antarctica Users should cite the original publication when using all or part of the data. In order to document CMIP6’s scientific impact and enable ongoing support of CMIP, users are also obligated to acknowledge CMIP6, ISMIP6 and the participating modeling groups. About the dataset: - The results are based on model output computed from the ISMIP6 native grids that vary between models. - The results are calculated over the ice-covered area of Antarctica, corrected for map projection errors, ice sheet model specific densities taken into account. - Results for the experiments 'exp*' are provided both as raw results and calculated as differences to the control experiment (ctrl_proj_open or ctrl_proj_std depending on the experiment). The later files are named with "minus_ctrl_proj" to indicate that the control run is substracted. - Results for ctrl_proj_open, ctrl_proj_std, hist_open and hist_std are not corrected to remove the control run. ----------------> Directory structure: groupname1 modelname1 expid computed_iareafl_AIS_groupname1_modelname1_expid.nc computed_iareafl_minus_ctrl_proj_AIS_groupname1_modelname1_expid.nc computed_iareagr_AIS_groupname1_modelname1_expid.nc computed_iareagr_minus_ctrl_proj_AIS_groupname1_modelname1_expid.nc computed_icearea_AIS_groupname1_modelname1_expid.nc computed_icearea_minus_ctrl_proj_AIS_groupname1_modelname1_expid.nc computed_ivol_AIS_groupname1_modelname1_expid.nc computed_ivol_minus_ctrl_proj_AIS_groupname1_modelname1_expid.nc computed_ivaf_AIS_groupname1_modelname1_expid.nc computed_ivaf_minus_ctrl_proj_AIS_groupname1_modelname1_expid.nc computed_smb_AIS_groupname1_modelname1_expid.nc computed_smb_minus_ctrl_proj_AIS_groupname1_modelname1_expid.nc computed_smbgr_AIS_groupname1_modelname1_expid.nc computed_smbgr_minus_ctrl_proj_AIS_groupname1_modelname1_expid.nc computed_bmbfl_AIS_groupname1_modelname1_expid.nc computed_bmbfl_minus_ctrl_proj_AIS_groupname1_modelname1_expid.nc ... ----------> Description of variables: icearea - ice area [m^2] iareafl - floating ice area [m^2] iareagr - grounded ice area [m^2] ivol - ice volume [m^3] ivaf - ice volume above floatation [m^3] smb - spatially integrated surface mass balance [kg/s] smbgr - spatially integrated surface mass balance over grounded ice [kg/s] bmbfl - spatially integrated basal melt rate under floating ice (negative for melting ice) [kg/s] Variables per file: rhoi - model specific ice density [kg m-3] rhow - model specific ocean water density [kg m-3] time - time, in years [variable] - global variable integrated over the Antarctica ice sheet [variable]_region_1 - variable integrated over West Antarctica [variable]_region_2 - variable integrated over East Antarctica [variable]_region_3 - variable integrated over the Antarctic Peninsula [variable]_sector_X - variable integrated over the X sector of the Antarctic ice sheet (18 sectors, from 1 to 18) -------------------> Data usage notice: If you use any of these results, please acknowledge the work of the people involved in producing them. Acknowledgements should have language similar to the below. "We thank the Climate and Cryosphere (CliC) effort, which provided support for ISMIP6 through sponsoring of workshops, hosting the ISMIP6 website and wiki, and promoted ISMIP6. We acknowledge the World Climate Research Programme, which, through it's Working Group on Coupled Modelling, coordinated and promoted CMIP5 and CMIP6. We thank the climate modeling groups for producing and making available their model output, the Earth System Grid Federation (ESGF) for archiving the CMIP data and providing access, the University at Buffalo for ISMIP6 data distribution and upload, and the multiple funding agencies who support CMIP5 and CMIP6 and ESGF. We thank the ISMIP6 steering committee, the ISMIP6 model selection group and ISMIP6 dataset preparation group for their continuous engagement in defining ISMIP6." You should also refer to and cite the following papers: https://doi.org/10.5194/tc-14-3033-2020, 2020. https://doi.org/10.5194/tc-14-2331-2020, 2020.

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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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    This data publication contains biostratigraphic age events for the CIROS-1 drill core, updated age ranges for a suite of samples from the McMurdo erratics sample collection, age-depth tie points for CIROS-1, CRP-2/2A, DSDP 270, DSDP 274, ANDRILL 2A and ANDRILL 1B, and glycerol dialkyl glycerol tetraethers (GDGTs) abundances and indices for samples from the McMurdo erratics, CIROS-1, CRP-2/2A, DSDP 270, DSDP 274, ANDRILL 2A, and ANDRILL 1B. All sample sites are in the Ross Sea region of Antarctica. The McMurdo erratics are glacial erratics collected in the McMurdo Sound region between 1991 and 1996 (Harwood and Levy, 2000). The CIROS-1 drill core was collected from McMurdo sound in 1986 with samples spanning the upper Eocene to lower Miocene. CRP-2/2A drill core was collected in 1999 from offshore Victoria Land with samples for this study from the upper Oligocene-lower Miocene. DSDP Site 270 was recovered from the Eastern Basin of the central Ross Sea in 1973, with samples spanning the upper Oligocene-lower Miocene. DSDP Site 274 was drilled on the lower continental rise in the northwestern Ross Sea in 1973, and samples for this study have been taken from the middle Miocene sections of the drill core. The ANDRILL-2A core was recovered in 2007 from Southern McMurdo Sound, samples span the lower Miocene to middle Miocene and data was originally published in Levy et al. (2016). The ANDRILL-IB core was drilled from the McMurdo Ice Shelf in 2006, samples are compiled from the Plio-Pleistocene section of the core and were originally published in McKay et al. (2012). Biostratigraphic age events are described for CIROS-1, expanding on and updating previously published age models and biostratigraphic ranges. Ages are also revised for the McMurdo erratics by updating the ages of the biostratigraphic markers described by (Harwood and Levy (2000) to more recently published age ranges. Age models for the sample sites are developed using published age datums and the Bayesian age-depth modelling functionality in the R package Bchron (Haslett and Parnell, 2008) to ensure a consistent approach for assigning ages to core depths between datums. GDGT abundances and indices for Ross Sea sites are presented to reconstruct ocean temperatures over the Cenozoic era. Detailed methodology for the processing and analysis of samples for GDGTs is described in the methods section of supplement paper. Further details are provided at: Duncan, B., McKay, R., Levy, R. et al. Climatic and tectonic drivers of late Oligocene Antarctic ice volume. Nat. Geosci. 15, 819–825 (2022). https://doi.org/10.1038/s41561-022-01025-x GET DATA: https://doi.org/10.1594/PANGAEA.946801

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    Diatom census counts were used to quantitatively estimate summer sea-surface temperatures (SST) over the last 40,000 years in core MD11-3353, collected in 2011 on board the R.V. Marion Dusfresne west of Kerguelen Island, Southern Ocean. The transfer function used to reconstruct summer (January to March) SST is the Modern Analog Technique that here uses 249 surface sediment samples (modern analogs), the relative abundances of 32 diatom species and the chord distance to select the five most similar modern analogs (Crosta et al., 2020). This method yields a root mean square error of prediction of ~1 °C. The core chronology is detailed in Thöle et al. (2019). RELATED PUBLICATION: Civel-Mazens, Matthieu; Crosta, Xavier; Cortese, Giuseppe; Michel, Elisabeth; Mazaud, Alain; Ther, Olivier; Ikehara, Minoru; Itaki, Takuya (2021): Impact of the Agulhas Return Current on the oceanography of the Kerguelen Plateau region, Southern Ocean, over the last 40 kyrs. Quaternary Science Reviews, 251, 106711, https://doi.org/10.1016/j.quascirev.2020.106711

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    This metadata record represents the data from 12 passive seismic stations at Kamb Ice Stream (site 1). Seismic stations measure vibrations in the ice providing boundary conditions and revealing controlling processes (ice-substrate interaction). Kamb Ice Stream ceased flowing from the West Antarctic Ice Sheet into the Ross Ice Shelf approximately 150 years. Stagnation of this ice stream has been attributed to changes in the routing of subglacial water. The KambSeis experiment targets a major subglacial drainage channel that crosses the ice-sheet ice-shelf transition and enters the sub ice shelf cavity. Using four small arrays surrounding the surface expression of the subglacial channel we aim to characterise drainage of subglacial water through the channel. GET DATA: http://ds.iris.edu/mda/5K/?timewindow=2019-2020

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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