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This dataset contains CCN concentrations at five supersaturation levels, averaged to 1 min time resolution, measured during the year-long Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) expedition from October 2019 to September 2020. The measurements were performed in the Swiss container on the D-deck of Research Vessel Polarstern, using the model CCN-100 from Droplet Measurement Technologies (DMT, Boulder, USA). Detailed description of the measurement principle can be found in e.g. Roberts & Nenes (2005). The instrument was located behind an automated valve, which switched hourly between a total and an interstitial air inlet, with upper cutoff sizes of 40 and 1 µm respectively (Heutte et al., Submitted; Beck et al., 2022; Dada et al., 2022). The measurements were performed in 1-h cycles, with a 0.5 L/min sample flow and a 2 L/min make up flow, where the supersaturations 0.15, 0.2, 0.3, 0.5 and 1.0 % were measured. The supersaturation of 0.15 % is measured for 20 min, as it takes longer to equilibrate, and the remaining supersaturations were measured for 10 min each. The instrument was calibrated in July 2019 before the campaign, and in March and April 2020 during the campaign. Based on the inter-variability of the calculated supersaturation levels during these calibrations, we can expect values ranging from 0.15-0.20, 0.20-0.25, 0.29-0.33, 0.43-0.5, 0.78-1.0 % for the nominal supersaturations of 0.15, 0.2, 0.3, 0.5 and 1.0 %, respectively. The counting error for the CCNC is associated with the error in the optical counting of particles and is about 10 %. Data were removed during the cooling cycle (i.e., the time when the measurement cycle starts again and the temperature is cooled to set the lowest supersaturation), which corresponds roughly to the first 10 min of each hour (so 50 % of the 0.15 % supersaturation period). Additionally, the first minute of the transition between supersaturations was removed before averaging the data to 1 min time resolution. During some time periods, a difference pattern of mean and standard deviation of the measurements between even and odd hours was observed, most probably caused by a persistent pressure drop in the inlet lines, resulting in a proportional reduction of the concentration measurements. For correction, the 1-h arithmetic mean of interstitial inlet measurements and the mean of the two adjacent hours of total inlet measurements were subtracted, and the resulting difference was added as a constant to the data points of the interstitial inlet measurements. The dataset contains a pollution mask for local pollution (predominantly exhaust from the Research Vessel Polarstern) with 0 indicating clean, and 1 indicating polluted periods (Beck et al., 2022; Beck et al., 2022).

These datasets contain the total particle number concentrations and normalized size distributions (dN/dlogDp) of excited, fluorescent, and hyper-fluorescent particles of sizes 0.5 to 20 μm (optical diameter). The normalized size distribution datasets are split into 20 size bins: 0.5 - 0.6 μm, 0.6 - 0.72 μm, 0.72 - 0.87 μm, 0.87 - 1.05 μm, 1.05 - 1.26 μm, 1.26 - 1.51 μm, 1.51 - 1.82 μm, 1.82 - 2.19 μm, 2.19 - 2.63 μm, 2.63 - 3.16 μm, 3.16 - 3.8 μm, 3.8 - 4.57 μm, 4.57 - 5.5 μm, 5.5 - 6.61 μm, 6.61 - 7.95 μm, 7.95 - 9.56 μm, 9.56 - 11.50 μm, 11.5 - 13.83 μm, 13.83- 16.63 μm and 16.63 - 20 μm. The data were measured by a WIBS-NEO (Wideband Integrated Bioaerosol Sensor, model New Electronics option) by droplet measurement techniques ltd. The data were processed using the IGOR WIBS toolkit V1.36 (DMT) and python version 3.9.7. These datasets have been averaged to 1 hour time resolution. The datasets were cleaned from local pollution sources by applying a pollution flag developed by Beck et al. (2022a,b), which is based on the rate of change in particle number concentration with 1 min time resolution. Data points with more than 10 polluted minutes within an hour were removed from the WIBS datasets. Time periods with zero filter measurements and time periods with unstable flow that affected number concentrations have been removed from the dataset. The WIBS measures the size, asymmetry and fluorescence of particles with an optical diameter of 0.5 – 20 µm. Detected particles are excited by two UV flashlamps at wavelengths of 280 and 370 nm and their emitted fluorescence is measured by two photomultipliers with bandwidths of 310 - 400 nm, and 420 - 650 nm. The WIBS counts excited particles at a maximum frequency of 125 Hz, which corresponds to a maximum concentration of 2.5*104 particles/L with a sample flow of 0.3 L/min. Excited particles were classified as fluorescent if their fluorescent intensity exceeded the background intensity by three standard deviations (3σ) and as hyper-fluorescent if the fluorescent intensity exceeded the background intensity by 9σ. Excited particles with a lower fluorescent intensity were considered to be non-fluorescent. The background fluorescence was determined by measuring the fluorescent signal in the measurement chamber in absence of particles. Background measurements were performed every 26 h. The combination of two excitation wavelengths and two detector wavebands allows the classification of fluorescent particles into seven types: A, B, C, AB, AC, BC, and ABC (Perring et al. (2015); Savage et al. (2017)). For further information about the instrumental setup, refer to Heutte et al. (Submitted).

We present an age model for the 651 m deep Skytrain Ice Rise ice core (79°44.5'S, 78°32.7'W). The top 2000 years have previously been dated using age markers interpolated through annual layer counting. Below this, we align the Skytrain core to the AICC2012 age model using tie points in the ice and air phase, and apply the Paleochrono program to obtain the best fit to the tie points and glaciological constraints. In the gas phase, ties are made using methane and, in critical sections, δ18Oair; in the ice phase ties are through 10Be across the Laschamps Event, and through ice chemistry related to long-range dust transport and deposition. This strategy provides a good outcome to about 108 ka (~605 m). Beyond that there are signs of flow disturbance, with a section of ice probably repeated. Nonetheless values of CH4 and δ18Oair confirm that part of the last interglacial (LIG), from about 117-126 ka (617-628 m), is present and in chronological order. Below this there are clear signs of stratigraphic disturbance, with rapid oscillation of values in both the ice and gas phase at the base of the LIG section. Based on methane values, the warmest part of the LIG and the coldest part of the penultimate glacial are missing from our record. Ice below 631 m appears to be of age >150 ka.

Stable isotope ratios from tree rings are important proxies of past climate variations. We have access to a calendar-dated wood material from wood collected at glacier forefields and peat bog sites located in the Alps. They are of two species, larch (Larix decidua) and cembran pine (Pinus cembra). All the wood samples were collected at high altitudes in the Swiss and Tyrol Alps, they cover the whole Holocene period and belong to the Eastern Alpine Conifer Chronology Dataset (Nicolussi et al., 2009; doi:10.1177/0959683609336565). We analysed the δ13C, δ18O and δ2H isotope ratios of alpha cellulose obtained from blocks of 5 annual rings from 203 trees. Cellulose was extracted following the modified Jayme-Wise method (Boettger et al., 2007; doi:10.1021/ac0700023). The isotopes values were determined using conventional Isotope Ratio Mass Spectrometry (Isoprime 100) coupled to a pyrolysis unit (HEKAtech GmbH, Germany), which is similar to the previously used TC/EA (for technical details see (Leuenberger 2007). This approach was extended to measurements of non-exchangeable hydrogen of alpha-cellulose using the on-line equilibration method (Filot et al., 2006 (doi:10.1002/rcm.2743); Loader et al., 2015(doi:10.1021/ac502557x)). The results are reported in per mil (‰) relative to the Vienna Pee Dee Belemnite (VPDB) for carbon and to Vienna Standard Mean Ocean Water (VSMOW) for hydrogen and oxygen (Coplen 1994; doi:10.1351/pac199466020273). For all the δ13C values after 1000 CE we applied the factor described in Leuenberger (2007; doi:10.1016/S1936-7961(07)01014-7) to correct for the δ13C depletion of CO2 caused by the Industrial Revolution from about 1850 onwards (Leuenberger, 2007).

Micropaleontological (coccolith, planktonic foraminifera) and geochemical (CaCO3, CaXRF, δ18O N. pachyderma, δ13C N. pachyderma) analyses from sediment core MD04-2718 retrieved from the Subantarctic zone (SAZ) of the Indian Southern Ocean covering the time interval from Marine Isotope Stage (MIS) 12 to MIS 10 (440,000– 360,000 years). Coccolith abundances and masses were performed using SYRACO software at Geoscience Paris-Saclay Laboratory (GEOPS). CaCO3 percentages were also measured at GEOPS. Foraminifera abundances and masses and stable oxygen and carbon isotopes were performed at Laboratoire des Sciences du Climat et de l'Environnement (LSCE). SST were calculated using two methods : the Modern Analogue Technique (Haddam et al., 2016) and the percentage of N. pachyderma s. (Govin et al., 2009). CaXRF measurements were performed at ETH, Zurich. These approaches allowed to decipher the variations in Carbonate Counter Pump and upwelling strength in the Indian Sector of the Southern Ocean between MIS 12 and MIS 10, including the Termination V and interglacial MIS 11.

There is a growing need for past weather and climate data to support science and decision-making. This paper describes the compilation and the construction of a global multivariable (air temperature, pressure, precipitation sum, number of precipitation days) monthly instrumental climate database that encompasses a substantial body of the known early instrumental time series. The dataset contains series compiled from existing databases that start before 1890 (though continuing to the present) as well as a large amount of newly rescued data. All series underwent a quality control procedure and subdaily series were processed to monthly mean values. An inventory was compiled, and the collection was deduplicated based on coordinates and mutual correlations. The data are provided in a common format accompanied by the inventory. The collection totals 12452 meteorological records in 118 countries. The data has been merged from 18250 original data files. The data can be used for climate reconstructions and analyses. It is the most comprehensive global monthly climate data set for the preindustrial period.

This archive contains raw data, intermediate and final results for the morphometric investigation of menardiform globorotallids (planktonic foraminifera) from ODP Hole 667A (Sierra Leone Rise in the eastern equatorial Atlantic Ocean; Lat: 4.569167°N, Lon: -21.911333°E ) from 33 stratigraphic levels during the past 8 million years. Complementary to previous investigations about the evolution in the Neogene Globorotalia menardii-G. limbata-G. multicamerata lineage from DSDP Holes 502 and 503, ODP Hole 925B and Hole 806C by Knappertsbusch, these data were collected to investigate the tempo and mode of evolution of the shell (=test) morphology and speciation. This dataset comprises digital images and morphometric measurements, as well as software (codes) needed to process the data according to the processing given in Friesenhagen (2022). Unpacked, the dataset has a size of 6.4 Gb (~66.500 files). The measured morphometric parameter of 6719 specimens incorporate, amongst others, the spiral height, axial length, the test area, the spiral and umbilical convexity, and the radii of the osculating circles of the upper and the lower keel region of the test in keel view. A subset of the data used in the study, their statistical treatment and illustrations of these are given alongside the publication as an electronic supplementary. The measured specimens, samples and their residuals are deposited in the micropalaeontological reference collection at the Natural History Museum Basel.

These sedimentological and geochemical analyses were carried out on three on-mound cold-water coral mound cores (MD13-3455G, MD13-3459G and MD13-3462G) recovered in the East Melilla Coral Province (Southeast Alboran Sea, Mediterranean Sea) during the EUROFLEETS cruise MD194 “Gateway” on board the RV Marion Dufresne II in June 2013. The time period of the studied core sections covers the last 15 ky and offers a high-resolution temporal record of the Bølling–Allerød interstadial. The core sites are situated approximately 1 km apart on the crest of Brittlestar Ridge I (35°26.087'N, 2°30.100'W). More precisely, the three datasets presented here correspond to: (1) particle size analysis results determined on the siliciclastic fraction using the Malvern Mastersizer 3000 at the Department of Geology at Ghent University. These analyses were carried out in order to quantify important changes in sediment flux and bottom current velocity. (2) Scanning X-ray fluorescence (XRF) was carried out using the Itrax high-resolution XRF core scanner at the Institute of Geological Sciences, University of Bern, to measure relative element concentration changes in the sediments of the cold-water coral mounds; whereas (3) RockEval6 pyrolysis was carried out at the Laboratory of Sediment Geochemistry at the University of Lausanne (Switzerland) to characterize the organic carbon content of the mound sediments

Over recent decades, the oxygen-deficient zones (ODZs) of the ocean have expanded, affecting marine ecosystems. However, their response to future global warming is poorly understood. In this study, we investigate Cenozoic ODZs dynamics extending back to 60 million years ago (60 Ma) with a special focus on two periods of sustained global warming: the Middle Miocene and Early Eocene climate optima (MMCO, ca. 16 Ma and EECO, ca 52 Ma). The data series include new species-specific, genus-specific and mixed-taxa foraminifera-bound nitrogen isotope (FB-δ15N) and N content data from sediment cores in the Pacific (ODP 872) and Atlantic (DSDP 516). The new FB-δ15N data combined with existing data from Kast et al., 2019 (doi: 10.1126/science.aau5784) are used to reconstruct the history of ODZ hosted water column denitrification across the Cenozoic. To better understand the connection between denitrification change and climate, we compare the nitrogen isotope data with new TEX86-derived sea surface temperature (SST) data from high latitudes (ODP 704), middle latitudes (DSDP/ODP 516, 588, 754, 1146, 1263) and low latitudes (ODP 667,730) in combination with a global Cenozoic TEX86-derived SST compilation of published records. The data series include all GDGT measurements, calculated indices, SSTs and SST gradients, as well as the age models for the discussed core sites (DSDP/ODP 516, 588, 667, 690, 704, 730, 738, 754, 1146, 1211, 1263) updated to the Geologic Time Scale 2012 (GTS-12, Gradstein et al., 2012, doi: 10.1016/C2011-1-08249-8).

Alkenone concentration and radiocarbon age in 7 gobally-distributed surface sediment samples and their associated grain-size fractions. Total organic carbon (TOC) and fractional abundance of grain-size fractions from bulk sediments (Bulk%) are taken from Ausín et al. (2021). Analytical precision of Uk'37 is 0.003 units. Uk'37-SST propagated error is ±0.51℃. These parameters were measured to explore the influence of alkenone-mineral associations and hydrodynamic mineral sorting processes on alkenone proxy signals. Bulk sediment samples were fractionated into four grain-size fractions (sand (>300-63 µm); coarse silt (63-10 µm); fine silt (10-2 µm); and clay (< 2 µm) prior to lipid extraction and manual column chromatography to obtain a ketone fraction containing the alkenones. The concentration and distribution of C37 alkenones was analyzed using gas chromatography with flame ionization detection (GC-FID) at the Biogeoscience Group Laboratories, ETH Zürich in 2018. The ketone fractions used for determination of alkenone concentration and unsaturation were further purified for compound specific radiocarbon analysis following Ohkouchi et al. (2005). Samples, were measured as CO2 using an Elemental-Analyzer system interface coupled to a gas ion source (GIS)-equipped Minicarbon Dating System (MICADAS) at the Laboratory of Ion Beam Physics, ETH Zürich in 2018. References Ausín, B., Bruni, E., Haghipour, N., Welte, C., Bernasconi, S. M., & Eglinton, T. I. Controls on the abundance, provenance and age of organic carbon buried in continental margin sediments. Earth and Planetary Science Letters, 558, 116759, doi:10.1016/j.epsl.2021.116759, 2021. Ohkouchi, N., Xu, L., Reddy, C. M., Montluon, D., & linton, T. I. Radiocarbon dating of alkenones from marine sediments: I. Isolation Protocol Radiocarbon, 47, 401-412, doi:10.1017/S0033822200035189, 2005.