Description: A new 21.3m firn core was drilled in 2015 at a coastal Antarctic high accumulation site in Adélie Land (66.78°S; 139.56°E, 602ma.s.l.). The core was dated by annual layers counting based on non-sea-salt sulfate and methanesulfonate summer peaks, refined by a comparison between the reconstructed surface mass balance (hereafter, SMB) and the closest available stake data. The mean reconstructed SMB of 75.2 ± 15.0cmw.e. y−1 is consistent with local stake data, and remarkably high for coastal East Antarctica. The resulting inter-annual and sub-annual variations in isotopic records (δ18O and deuterium excess, hereafter d-excess) are explored for 1998–2014 and are systematically compared with a couple of climatic time series: an updated database of Antarctic surface snow isotopic composition, SMB stake data, meteorological observations from Dumont d'Urville station, sea-ice concentration based on passive microwave satellite data, precipitation outputs of atmospheric reanalyses, climate and water stable isotope outputs from the atmospheric general circulation model ECHAM5-wiso, as well as air mass origins diagnosed using 5-days back-trajectories. The mean isotopic values (−19.3 ± 3.1‰ for δ18O and 5.4 ± 2.2‰ for d-excess) are consistent with other coastal Antarctic values. No significant isotope-temperature relationship can be evidenced at any timescale, ruling out a simple interpretation of in terms of local temperature. An observed asymmetry in the δ18O seasonal cycle may be explained by the precipitation of air masses coming from Indian and Pacific/West Antarctic Ice Sheet sectors in autumn and winter times, recorded in the d-excess signal showing outstanding values in austral spring versus autumn. Significant positive trends are observed in the annual d-excess record and local sea-ice extent (135°E–145°E) over the period 1998–2014. However, processes studies focusing on resulting isotopic compositions and particularly the d-excess-δ18O relationship, evidenced as a potential fingerprint of moisture origins, as well as the collection of more isotopic measurements in Adélie Land are needed for an accurate interpretation of our signals.

Description: This dataset presents measurements of stable isotopes in water (δD and δ18O) from Lake Locknesjön, Sweden. Water samples were collected between 2013 and 2018 and were taken from different depths down to 20 m in the lake, as well as from the lake's main tributary and its outflow. Depending on the depth, the water samples were collected from the shore, by a diving team, or with a UWITEC gravity corer. Measurements of stable isotopes in water samples were conducted at the Laboratoire des Sciences du Climat et de l'Environnement (LSCE), Gif-sur-Yvette, France. The δ18O was measured with a Finnigan MAT252 isotope ratio mass spectrometer with a precision of ±0.05‰ (two standard deviations). The δD was measured with a Picarro Analyzer (Cavity Ring-Down Spectroscopy) with a precision of±0.7‰ (one standard deviation).

Description: This dataset presents measurements of stable isotopes in biogenic carbonates (δ13C and δ18O) from Lake Locknesjön, Sweden. Carbonate samples were collected in 2018 from different lacustrine organisms along a water depth gradient from 0 to 8 m depth: encrustations from the calcifying algae Chara hispida, valves from the bivalve mollusk Pisidium sp., and valves from two species of ostracods, Candona candida and Candona neglecta. Adult specimen and different juvenile stages of the ostracods were sampled. The carbonate samples originate from living organisms, i.e. which were alive at the time of sampling in 2018, and from their subfossil remains in the uppermost centimeter of the lake sediments. The carbonate samples were collected by a diving team. Carbonate isotope measurements were carried out at MARUM, Bremen, Germany, using a ThermoFisher Scientific 253plusgas isotope ratio mass spectrometer with a Kiel IV automated carbonate preparation device. The standard deviation of the reference standards over the measurement period was 0.06‰ for δ18O and 0.03‰ for δ13C.

Description: d18O atmospheric (permill) and dO2/N2 atmospheric (permill) measured on TALDICE ice core between 1356 and 1617 m depth. The d15N, d18Oatm and dO2/N2 (permill) ratios are measured in the air extracted from 81 ice samples between 1356 m depth and 1620 m depth. The extraction of air trapped in the ice is performed at LSCE, using a semi-automatic extraction line (Capron et al., 2010), and δ18Oatm, δ15N and δO2/N2 of air are measured using a dual inlet Delta V plus (Thermo Electron Corporation) mass spectrometer.

Description: TALDICE deep1 ice core chronology (years) for the TALDICE ice core for ice and gas matrix between 1438 m depth and 1548 m depth at 1 m resolution. The chronology is correlated with accumulation rate, thinning function and LIDIE (lock-in-depth in ice equivalent). The TALDICE deep1 chronology is defined for both gas and ice matrix between 1438 m depth and 1548 m depth with the application of the IceChrono1 model (Parrenin et al. 2015). The age scale is defined at 1 m resolution and gas and ice age ages (expressed in years) with their respective uncertainties. The chronology is correlated with accumulation rate, thinning function and LIDIE (lock-in-depth in ice equivalent).

Description: Abstract: We present here a high resolution (0.11 m) dataset of the isotopic composition of the ice (δ¹⁸O) from the EPICA Dome-C ice core. The dataset covers the depth range 7.81-3189.89 m (0.05-802.427 ka). Analysis is performed in Copenhagen with a CO~2~ equilibration Mass Spectrometry system (Finnegan MAT 251). Samples of 5 ml are equilibrated with CO~2~ for 6 hours under vibrations, thereafter injected to the mass spectrometer where the ¹⁸O/¹⁶O ratio is obtained on masses 46 and 44. All measurements reported on the SMOW-SLAP scale using a 2-point linear calibration (standards used: Crete: -33.61 ‰ and DC02: -54.11 ‰ . The combined uncertainty of the record is 0.07 ‰. We interpolate the dataset on the AICC2012 chronology.

Description: dD (permill) measured on TALDICE ice core at 5 cm resolution between 1438 m depth and 1619 m depth associated with ice age defined by the TALDICE 1a chronology. The dD measurements (permill) are performed between 1438 m depth until 1620 m depth at 5 cm and 10 cm resolution. Discrete samples at 10 cm-resolution between 1438 m and 1486 m depth are measured at the University of Venice using a Thermo Fisher Delta Plus Advantage mass spectrometer coupled with a HDO device. The precision of δD measurements is ± 0.7‰ (1σ). Below 1486 m depth, discrete 5 cm-resolution analyses are carried out the University of Venice and LSCE using the Cavity Ring Down Spectroscopy technique (CRDS). Analysis are performed using a Picarro isotope water analyser (L2130-i version) for both laboratories. The data are calibrated using a linear calibration with three lab-standards periodically calibrated vs V-SMOW.

Description: d15N (permill) measured on TALDICE ice core between 1356 and 1617 m depth. The data set includes new data published in Crotti et al. (2021), Bazin et al. (2013) and Buiron et al. (2011). The d15N, d18Oatm and dO2/N2 (permill) ratios are measured in the air extracted from 81 ice samples between 1356 m depth and 1620 m depth. The extraction of air trapped in the ice is performed at LSCE, using a semi-automatic extraction line (Capron et al., 2010), and δ18Oatm, δ15N and δO2/N2 of air are measured using a dual inlet Delta V plus (Thermo Electron Corporation) mass spectrometer.

Description: TALDICE (TALos Dome Ice CorE) is a 1620 m deep ice core drilled at Talos Dome, an ice dome located at the edge of the East Antarctic Plateau in the Ross Sea Sector. Here are presented new measurements on TALDICE ice core used to define the TALDICE-deep1 chronology between 1438 m and 1548 m depth. The new age scale extends the climate record for the Ross Sea Sector of the East Antarctic Ice Sheet back to MIS 10.1. Here we present new measurements on the deeper part of the TALDICE ice core.

Description: A new 21.3m firn core was drilled in 2015 at a coastal Antarctic high-accumulation site in Adélie Land (66.78◦ S; 139.56◦ E, 602 m a.s.l.), named Terre Adélie 192A (TA192A). The mean isotopic values (−19.3 ‰ ± 3.1 ‰ for δ18O and 5.4 ‰±2.2 ‰ for deuterium excess) are consistent with other coastal Antarctic values. No significant isotope–temperature relationship can be evidenced at any timescale. This rules out a simple interpretation in terms of local temperature. An observed asymmetry in the δ18O seasonal cycle may be explained by the precipitation of air masses coming from the eastern and western sectors in autumn and winter, recorded in the d-excess signal showing outstanding values in austral spring versus autumn. Significant positive trends are observed in the annual d-excess record and local sea ice extent (135–145◦ E) over the period 1998–2014. However, process studies focusing on resulting isotopic compositions and particularly the deuterium excess–δ18O relationship, evidenced as a potential fingerprint of moisture origins, as well as the collection of more isotopic measurements in Adélie Land are needed for an accurate interpretation of our signals.