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  • The dataset comprises of analyses of two sediment cores (LC12 and LC7), extracted from Blaso, a large epishelf lake on the margin of 79 degrees N Ice Shelf, NW Greenland in July-August 2017. The data are used to constrain ice shelf dynamics over the last 8500 calibrated years before present (cal. years B.P., where present is A.D. 1950). Data for the LC7 and LC12 sediment records consist of radiocarbon (14C) chronology data. Overlapping 2 m-long sediment cores were recovered with a UWITEC KOL ''Kolbenlot percussion piston corer to a total sediment depth of 3.74 m (LC7) and 5.24 m (LC12). Accelerator mass spectrometry (AMS) was used for radiocarbon (14C) dating. Core LC7: 87 m water depth; 79.589 degrees N, 22.494 degrees E. Core LC12: 90 m water depth; 79.5948 degrees N, 22.44233 degrees E. This project was funded by the Natural Environment Research Council (NERC) through Standard Grant NE/N011228/1. We thank the Alfred Wegner Institute, and particularly Angelika Humbert and Hicham Rafiq, for their significant logistic support through the iGRIFF project. Additional support was provided from Station Nord (Jorgen Skafte), Nordland Air, Air Greenland and the Joint Arctic Command. Naalakkersuisut, Government of Greenland, provided Scientific Survey (VU-00121) and Export (046/2017) licences for this work

  • Changes of circulation pattern in the Southern Ocean have been invoked to explain a significant portion of the increase in the atmospheric carbon dioxide during the last deglaciation. However, the accurate timing and thus underlying mechanisms of these changes are still controversial, requiring knowledge of different water masses movements with absolute age constraints. Aragonitic scleractinian deep-sea corals, recovered from a broad range of depths in the Drake Passage, provide a unique opportunity to investigate Southern Ocean ventilation with precise U-Th age control. A rapid age-screening technique achieved by coupling a laser system to Multi-Collector Inductively Coupled Plasma Mass Spectrometry (MC-ICPMS) enables us to get an approximate age distribution of the coral samples in order to select appropriate specimens for more accurate isotope-dilution age and radiocarbon age determination. Thus far more than 1800 deep-sea corals from the Drake Passage have been dated using this and other techniques, and about 400 samples have been dated precisely using isotope-dilution method. The age results show that deep-sea corals can be found across nearly the whole of the last deglaciation across a wide range of depths and locations. With known radiocarbon contents and U-Th ages of the deep-sea corals, the ventilation state of different water masses in the past can be assessed based on their decay-corrected 14C activities. This data submission includes all U-Th and 14C data available for the Drake Passage corals. Funding was provided by the NERC standard grant NE/N003861/1.

  • The dataset comprises reconstructed temperature and tephra deposits age data from Yanou Lake, Fildes Peninsula, King George Island, South Shetland Islands. Data are calibrated to the 2020 radiocarbon calibration curves. The Antarctic and global glycerol dialkyl glycerol tetraether (GDGT) lipid biomarker temperature calibration are included. GDGT MSAT (mean summer air temperature) data was obtained by recalibrating the Pearson et al. (2011) global and Foster et al. (2016) Antarctic lake surface GDGT MSAT datasets. This dataset includes updates with new calibration of data originally published in Roberts et al. (2017). These revisions were funded as part of the IMCONet (FP7 IRSES, action no. 318718) program led by Doris Abele (AWI); the Natural Environment Research Council (NERC/BAS-CGS Grant no.81); the NERC/BAS science programmes CACHE-PEP: Natural climate variability - extending the Americas palaeoclimate transect through the Antarctic Peninsula to the pole and GRADES-QWAD: Quaternary West Antarctic Deglaciations.

  • The dataset comprises of sedimentological, geochemical, biological and chronological data from a sediment core record extracted from Kiteschsee Lake sediment, Fildes Peninsula, King George Island, South Shetland Islands. We undertook multi-proxy analyses (diatom, grain size, geochemical and sedimentological) on a 77 cm-long sediment record extracted from the flat-bottomed eastern basin depocentre of Kiteschsee Lake and compared data obtained with published lake records from the Fildes Peninsula. Data collected in this study were funded by: Centro de Investigaciones en Ciencias de la Tierra (CICTERRA), the Direccion Nacional del Antartico/Instituto Antartico Argentino (DNA/IAA) in the framework of the Project PICTA, 2011 - 0102, IAA "Geomorfologia y Geologia Glaciar del Archipielago James Ross e Islas Shetland del Sur, Sector Norte de la Peninsula Antartica"; the Alfred Wegener Institute (AWI) research program Polar regions and Coasts in a changing Earth System (PACES II); IMCONet (FP7 IRSES, action no. 318718); the Natural Environment Research Council (NERC/BAS-CGS Grant no.81); the NERC/BAS science programmes CACHE-PEP: Natural climate variability - extending the Americas palaeoclimate transect through the Antarctic Peninsula to the pole and GRADES-QWAD: Quaternary West Antarctic Deglaciations. We thank the crews of the Argentine research station "Carlini" and the adjoined German Dallmann-Labor (AWI) Laboratory, the Uruguayan research station "Artigas", the Russian Bellingshausen Station, the Chinese Great Wall Station, Base Presidente Eduardo Frei Montalva, the Brazilian Navy Almirante Maximiano, the UK Navy HMS Endurance and NERC/BAS James Clark Ross for logistical support during the 2006, 2011, 2014 and 2015 field seasons.