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The data here described are presented in the submitted paper Response of the Wilkes Subglacial Basin Ice Sheet to Southern Ocean Warming During Late Pleistocene Interglacials by Crotti et al. This data set includes new high resolution measurements of d-excess, d18O and ssNa+ for the Antarctic TALDICE ice core (Latitude: -72.783330, Longitude: 159.066670, Elevation: 2315.0 m). The new data set covers the interglacials periods of MIS 5.5, MIS 7.5 and MIS 9.3 (1486 m depth - 1548 m depth). The data are drawn on the TALDICE deep1 chronology (Crotti et al. 2021). The d-excess (d = δD − 8 × δ18O) (permill) record covers the periods MIS 5.5 , MIS 7.5 and 9.3 MIS is at 5 cm resolution and spans the following age-depths intervals: • MIS 5.5. Between 1378.5 and 1421.65 m depth, 110-135 ka • MIS 7.5. Between 1521.85 and 1524.5 m depth, 243-248 ka • MIS 9.3. Between 1541.80 and 1547.90 m depth, 320-343 ka The d18O record (permill) covers the periods MIS 5.5 , MIS 7.5 and 9.3 MIS is at 5 cm resolution and spans the following age-depths intervals: • MIS 7.5. Between 1521.85 and 1524.5 m depth, 243-248 ka • MIS 9.3. Between 1541.80 and 1547.90 m depth, 320-343 ka The ssNa+ fluxes record covers the periods MIS 5.5 , MIS 7.5 and 9.3 MIS is at 8 cm resolution and pans the following age-depths intervals: • MIS 7.5. Between 1521.81 and 1524.54 m depth, 243-248 ka • MIS 9.3. Between 1541.73 and 1547.96 m depth, 320-343 ka The d18O and dD (non presented here) to calculate the d-excess were analysed in Italy (University of Venice) and France (LSCE) using the Cavity Ring Down Spectroscopy (CRDS) technique. Analyses were performed using a Picarro isotope water analyser (L2130-i version for both laboratories). The data were calibrated using a three-point linear calibration with three lab-standards that were themselves calibrated versus Standard Mean Ocean Water (SMOW). The average precision for the δ18O and δD measurements is 0.1 and 0.7 ‰, respectively. The concentrations of ssNa+ were measured on TALDICE ice samples at 8 cm resolution by classical ion chromatography on discrete samples collected using a melting device connected to an auto-sampler for the MIS 7.5 and MIS 9.3 whereas Continuous Flow Analysis (CFA) was applied for MIS 5.5 samples. The total deposition ssNa+ flux was calculated multiplying the measured ice concentration of ssNa+ by the reconstructed accumulation rate. The accumulation rates were derived from the accumulation rates were obtained from the TALDICE deep1 age scale (Crotti et al. 2021).

The data collection consists of 3 datasets: - Zooplankton standing stocks: this dataset compiles the standing stocks (ind/m³), the integrated standing stocks (ind/m²) and the integrated CaCO3 standing stocks (mg/m²) for three groups of zooplanktonic calcifying organisms, pteropods, heteropods and foraminifers. The organisms were collected by oblique towing (Ø 0.5 m, 90 μm mesh size, SeaGear mechanical flowmeter) in the North Pacific between Hawaii and the Gulf of Alaska during the R/V Kilo Moana cruise KM1712 in August 2017. The sampling strategy was designed to capture an integrated sample of all foraminifers, pteropods and heteropods from juveniles to adults living throughout the upper water column. - Phytoplankton standing stocks: this dataset compiles the CaCO3 standing stocks of living coccolithophores (mg/m³), of detached coccoliths (mg/m³) and the integrated CaCO3 standing stocks of coccolithophores (mg/m²). The samples were collected in the North Pacific between Hawaii and the Gulf of Alaska during the R/V Kilo Moana cruise KM1712 in August 2017, with rosette Niskin bottles equiped with CTD (Sea-Bird SBE 9) at different depths throughout the photic zone including the deep chlorophyll maximum. - Integrated CaCO3 production: this dataset compiles the estimates of annual CaCO3 production, including the upper and lower limits of the estimates, for the 4 planktic calcifying groups considered in the study, the pteropods (mg/m²/yr), the heteropods (mg/m²/yr), the foraminifers (mg/m²/yr) and the coccolithophores (mg/m²/yr). The estimates derived from the living standing stocks of these 4 groups of organisms collected in the North Pacific between Hawaii and the Gulf of Alaska during the R/V Kilo Moana cruise KM1712 in August 2017.

Palaeo-environmental and -climatic data from core CEN-17.4 from the central Congo peatlands, Likouala Department (1°11'0.49"N, 17°38'23.7"E) and data from supporting cores. Bulk organic (TOC, TN, C/N) data and Rock Eval data to assess peat occurrence and degradation status for the central core CEN-17.4 and supporting cores. Radiocarbon dates on fine fractions for all cores. Plant-wax derived n-alkane stable carbon (δ^13^C) and stable hydrogen (δD) isotope data to assess vegetation changes and rainfall changes for the central core CEN-17.4. Selected pollen data for the central core CEN-17.4 to assess palaeo-ecological changes.

The data consist of ~600 U-Th ages of scleractianian cold-water corals dated by laser ablation and isotope dilution methods covering the last 150,000 years. The corals are from three locations: Reykjanes Ridge (57°N to 61°N, 28°W to 33°W); Tropic Seamount (23°55'N, 20°45'W); and the East Equatorial Atlantic from Carter (9°N, 21°W) and Knipovich seamounts (5°N, 27°W). The samples were collected with ROV and dredges during the cruises: CE0806 in 2008 (Reykjanes Ridge); JC094 in 2013 (Equatorial Atlantic); and JC142 in 2016 (Tropic Seamount). Additionally, a compilation of ~750 U-Th and 14C ages of scleractianian cold-water corals from the Northeast Atlantic Ocean is presented. The complete dataset is used to investigate the temporal and spatial coral distribution at Northeast Atlantic Ocean and the relation with past climatic events.

A global compilation of in situ data is vital to evaluate the quality of ocean-colour satellite data records. Here, we describe data compiled for the validation of ocean-colour products from the ESA Ocean Colour Climate Change Initiative (OC-CCI). The data were acquired from several sources (including, inter alia, MOBY, BOUSSOLE, AERONET-OC, SeaBASS, NOMAD, MERMAID, AMT, ICES, HOT, GeP&CO) and span the period from 1997 to 2021. Observations of the following variables were compiled: spectral remote-sensing reflectance, concentration of chlorophyll-a, spectral inherent optical properties, spectral diffuse attenuation coefficient and total suspended matter. The data were obtained from multi-project archives acquired via open internet services, or from individual projects, acquired directly from data providers. Methodologies were implemented for homogenisation, quality control and merging of all data. No changes were made to the original data, other than averaging of observations that were close in time and space, elimination of some points after quality control and conversion to a standard format. The result is a merged table available in text format. Metadata of each in situ measurement (original source, cruise or experiment, principal investigator) were propagated throughout the work and made available in the final table. By making the metadata available, provenance is better documented, and it is also possible to analyse each set of data separately. This paper also describes the changes that were made to the compilation in relation to the previous version.

Coccolithophores are globally important marine calcifying phytoplankton that utilize a haplo-diplontic life cycle. The haplo-diplontic life cycle allows coccolithophores to divide in both life cycle phases and potentially expands coccolithophore niche volume. Research has, however, to date largely overlooked the life cycle of coccolithophores and has instead focused on the diploid life cycle phase of coccolithophores. Through the synthesis and analysis of global scanning electron microscopy (SEM) coccolithophore abundance data (n=2534), we find that calcified haploid coccolithophores generally constitute a minor component of the total coccolithophore abundance (≈ 2 %–15 % depending on season). However, using case studies in the Atlantic Ocean and Mediterranean Sea, we show that, depending on environmental conditions, calcifying haploid coccolithophores can be significant contributors to the coccolithophore standing stock (up to ≈30 %). Furthermore, using hypervolumes to quantify the niche of coccolithophores, we illustrate that the haploid and diploid life cycle phases inhabit contrasting niches and that on average this allows coccolithophores to expand their niche by ≈18.8 %, with a range of 3 %–76 % for individual species. Our results highlight that future coccolithophore research should consider both life cycle stages, as omission of the haploid life cycle phase in current research limits our understanding of coccolithophore ecology. Our results furthermore suggest a different response to nutrient limitation and stratification, which may be of relevance for further climate scenarios. Our compilation highlights the spatial and temporal sparsity of SEM measurements and the need for new molecular techniques to identify uncalcified haploid coccolithophores. Our work also emphasizes the need for further work on the carbonate chemistry niche of the coccolithophore life cycle.

Organic carbon (OC) stored in Arctic permafrost represents one of Earth's largest and most vulnerable terrestrial carbon pools. Amplified climate warming across the Arctic results in widespread permafrost thaw. Permafrost deposits exposed at river cliffs and coasts are particularly susceptible to thawing processes. Accelerating erosion of terrestrial permafrost along shorelines leads to increased transfer of organic matter (OM) to nearshore waters. However, the amount of terrestrial permafrost carbon and nitrogen as well as the OM quality in these deposits are still poorly quantified. Here, we characterise the sources and the quality of OM supplied to the Lena River at a rapidly eroding permafrost river shoreline cliff in the eastern part of the delta (Sobo-Sise Island). Our multi-proxy approach captures bulk elemental, molecular geochemical and carbon isotopic analyses of late Pleistocene Yedoma permafrost and Holocene cover deposits, discontinuously spanning the last ~52 ka. We show that the ancient permafrost exposed in the Sobo-Sise cliff has a high organic carbon content (mean of about 5 wt%).We found that the OM quality, which we define as the intrinsic potential to further transformation, decomposition, and mineralization, is also high as inferred by the lipid biomarker inventory. The oldest sediments stem from Marine Isotope Stage (MIS) 3 interstadial deposits (dated to 52 to 28 cal kyr BP) and is overlaid by Last Glacial MIS 2 (dated to 28 to 15 cal ka BP) and Holocene MIS 1 (dated to 7–0 cal ka BP) deposits. The relatively high average chain length (ACL) index of n-alkanes along the cliff profile indicates a predominant contribution of vascular plants to the OM composition. The elevated ratio of iso and anteiso-branched FAs relative to long chain (C ≥ 20) n-FAs in the interstadial MIS 3 and the interglacial MIS 1 deposits, suggests stronger microbial activity and consequently higher input of bacterial biomass during these climatically warmer periods. The overall high carbon preference index (CPI) and higher plant fatty acid (HPFA) values as well as high C / N ratios point to a good quality of the preserved OM and thus to a high potential of the OM for decomposition upon thaw. A decrease of HPFA values downwards along the profile probably indicates a relatively stronger OM decomposition in the oldest (MIS 3) deposits of the cliff.

We studied the distribution of coccoliths in surface sediments across the Drake Passage and calcification of Emiliania huxleyi morphotypes in surface sediment samples retrieved during PS97. Dataset 1 (morphometrical measurements and mass estimations) is reporting the morphometrical measurements of E. huxleyi coccoliths measured with the Coccobiom2 macro (Coccobiom2 macros: http://ina.tmsoc.org/nannos/coccobiom/Usernotes.html, last access: 3 September 2016) based on 570 Scanning Electron Microscope images (showing E. huxleyi coccoliths of morphotypes A, Aovercalcified, B/C and O), and calcite mass estimations based on two different formulas 1) after Beuvier et al. 2019 (doi:10.1038/s41467-019-08635-x) and 2) after Young and Ziveri 2000 (doi:10.1016/S0967-0645(00)00003-5). The morphometrical measurements (in µm) include coccolith distal shield length, distal shield width, Central Area length, Central Area width. The mass estimations (in pg) include the mass calculated after 1) and 2) and the respective shape factor used for 2). The coccoliths stem from surface sediments that were sampled with a Multicorer and are approximately of Mid to Late Holocene Age. Dataset 2 (morphotype counts) is reporting the relative number of E. huxleyi morphotypes per sample, based on an additional count with the SEM. Further details in the material and methods section in the corresponding paper.

Plasticity in developmental trajectories has been proposed to contribute to species divergence but finding evidence for plasticity-led evolution in the fossil record remains challenging. Here we use high-resolution imaging techniques to map developmental change in Globorotalia plesiotumida–tumida lineage of planktic foraminifera from late Miocene until Recent. The unique mode of foraminiferal growth by the addition of chambers onto a calcite shell means that adult fossils retain information about their developmental history. All study specimens were obtained from the ODP in Western Caribbean, Leg 165, Sites 1000 and 999. We first assessed change in cumulative chamber volume and surface area at each chamber addition during the transition between the ancestral G. plesiotumida and its descendant G. tumida from 6.3 Ma to 5.3 Ma using five specimens reconstructed from Synchrotron X-Ray microtomography scans. This was complemented with measurements from 63 specimens reconstructed using X-Ray microtomography from five populations at 7.3 Ma, 6.3 Ma, 5.6 Ma, 5.3 Ma and 0.25 Ma. In addition, we characterised the external morphology of all study specimens by measuring their total length and coiling direction (n = 78). Our dataset shows that the transition interval in this lineage is characterised by an increase in variability in cumulative chamber volume compared to samples outside of this range. We also find that the transition is marked by a distinct shift in developmental trajectory and coiling direction in support of a rapid lineage division rather than gradual change. The large variation in developmental trajectories that we uncover emphasises the need for high-throughput approaches in studies of developmental change in the fossil record.

This data set includes measurement during the CACOON 2019 expeditions (Fuchs et al., 2021; Strauss et al., 2021) in the Lena Delta region in Siberia. The data collection took place during two field campaigns; the first one was in March-April 2019, the second one in August 2019. Measurements were taken with a handheld SontekTM CastAway sensor with an integrated GPS. The measured data include pressure (dbar; accuracy: 0.25%), depth (m; ±0.25%), temperature (°C; ±0.05°C), conductivity (mS/cm; 0.25%±0.005 mS/cm), specific conductance (mS/cm; 0.25%±0.005 mS/cm), salinity (practical salinity scale; ±0.1), sound velocity (m/s; ±0.15 m/s), and density (kg/m3; ±0.02 kg/m3). In total, 31 depth profiles were measured from the Sardakhskaya main river channel in the Lena Delta to 80 km offshore in the Laptev Sea to specifically target the mouth area of the Sardakhskaya channel. The CTD was lowered from water surface with an additional ballast to make sure the small CTD device reached the sea (or river) bed. The data consists of two data sheets. The first one (CTD cast locations in the Lena Delta region) includes detailed data about the locations and time of CTD measurements; the second data sheet (CTD measurements in the Lena Delta region) includes the CTD data from all the measured locations.