ALBERT

Description: The presence-absence data for macrobenthic fauna that has been collected in Mingulay Reef Complex (Scotland, UK) across 79 stations over the years 2003, 2005, 2009, 2010 and 2011. The collection of the benthic samples has been carried out using a Van-Veen grab, mainly from hard habitats (e.g. live and dead coral framework). About 60% of the macrofaunal specimens have been identified at species level using high quality taxonomic keys and advice from taxonomy experts. Most common taxonomic groups analysed here are molluscs, polychaetes, arthropods, bryozoans, anthozoans, tunicates and brachiopods. The collection of the specimens is now deposited at the National Museums of Scotland (see the attached excel file for details). The enviromental data contains information about coordinates and environmental settings at stations where macrobenthic samples mentioned above, were collected. The environmental settings that are included in the file refer to the years 2003, 2005, 2009, 2010, 2011. For more information on the environmental variables have a look in Henry et al. 2010 (doi:10.1007/s00338-009-0577-6) and Henry et al. 2013 (doi:10.5194/bg-10-2737-2013). The environmental variables included in the excel file are: type of macrohabitat (i.e. muddy sand, rubble, rock, live coral, dead framework, live & dead framework), depth (m), slope, ruggedness, broad-scale bathymetric position index, fine-scale bathymetric position index, average current speed (m/s), maximum current speed (m/s), northness, eastness, winter North Atlantic Oscillation Index (same year), winter North Atlantic Oscillation Index (previous year), annual average bottom temperature (same year), annual average bottom salinity (same year). Extraction of bathymetric (depth) and topographic data [slope, aspect, northness, eastness, ruggedness, standardised broad-scale bathymetric position index (BPI; with an inner radius of 1 cell and an outer radius of 5 cells), fine-scale BPI (with an inner radius of 1 cell and an outer radius of 3 cells)] was based on multibeam echosounder data, using the Spatial Analyst and Benthic Terrain Modeler toolboxes in ArcGIS v.10.6.1 Average and maximum current speed values (m/s) were extracted by the ArcGIS v. 10.6.1 Spatial Analyst toolbox using data generated by a high-resolution 3D ocean model created for the MRC by Moreno-Navas et al. (2014). Data for the winter NAOI (DJFM) (Hurrell et al., 2003) were downloaded from the National Center for Atmospheric Research/University Corporation for Atmospheric Research website (climatedataguide.ucar.edu; data accessed on 28/02/2019).

Description: The Antarctic Circumpolar Current is the world's largest current system connecting all major ocean basins of the global ocean. Its flow, driven by strong westerly winds, is constricted to its narrowest extent in the Drake Passage, located between South America and the Antarctic Peninsula. Due to the remoteness of the area, harsh weather conditions and strong bottom currents, sediment recovery is difficult and data coverage is still inadequate. Here, we report on the composition of 51 surface sediments collected during the R/V Polarstern PS97 expedition (February-April 2016) across the western and central Drake Passage, from the Chilean/Argentinian continental margin to the South Shetland Islands and the Bransfield Strait (water depth: ∼100-4000 m). We studied microfossils (diatoms), bulk sediment composition and geochemical proxies (biogenic opal, organic carbon, calcium carbonate, carbon and nitrogen stable isotopes, sterols and photosynthetic pigments), and evaluated how they respond to, and reflect oceanic domains and polar to subpolar frontal systems in this region. Our multi-proxy approach shows a strong relationship between the composition of surface sediments and ocean productivity, terrigenous input, intensity of ocean currents, and ice proximity, clearly differentiating among 4 biogeographical zones. The Subantarctic Zone was characterized by warmer-water diatoms, high carbonate (〉45%) and low organic carbon contents (avg. 0.26%), as well as low concentrations of pigments (avg. 1.75 μg/g) and sterols (avg. 0.90 μg/g). A general N-S transition from carbonate-rich to opal-rich sediment was observed at Drake Passage sites of the Polar Front and Permanently Open Ocean Zone. These sites were characterized by low organic carbon content (0.22%), high relative abundances of heavily silicified diatoms (≥60% Fragilariopsis kerguelensis), and abundant foraminifera at shallower stations. Approaching the Antarctic Peninsula in the Transitional Zone, an increase in the concentrations of pigments and sterols (avg. 2.57 μg/g and 1.44 μg/g, respectively) and a strong decrease in carbonate content was observed. The seasonal Sea-Ice Zone in the southern section of the study area, had the highest contents of biogenic opal (avg. 14.6%) and organic carbon (avg. 0.7%), low carbonate contents (avg. 2.4%), with the occurrence of sea-ice-related diatoms and sterols. In all zones, terrigenous input was detected, although carbon/nitrogen ratios and δ13Corg suggest a predominance of marine-derived organic matter; lower values of δ13Corg occurred south of the Polar Front. The new results presented here constitute a highly valuable reference dataset for the calibration of microfossil and geochemical proxies against observational data and provide a useful regional baseline for future paleo-research.

Description: This dataset includes counts, percentages and concentrations of all dinoflagellate cyst taxa identified in the benthic nephloid layer (BNL), cyst rain and surface sediments collected along a land-sea transect off Figueira da Foz (NW Portugal, Atlantic Iberian margin) during the Hydrographic Institute (IH)-HABWAVE cruise (16th-19th September 2019). Sampling of the dinoflagellate cyst community in the BNL, the water column (sediment trap) and the surface sediments (together with studies of spatio-temporal changes in physical properties) were carried out in order to investigate the dinoflagellate cyst distribution and the factors (physical and biological) affecting it. Water samples for cyst analyses were collected by a rosette firing system associated with the CTD, and the cyst rain using a sediment trap situated above the BNL. They were filtered (40-47 l) on board through a 150µm-nylon mesh sieve onto a 10µm-calibrated stainless steel sieve (Retsch). In the laboratory, cysts were concentrated by centrifugation. Full and empty cysts were counted to investigate whether a reservoir of viable cysts existed in the BNL. Surface sediments were sampled with a Smith McIntyre grab and using Plexiglass tubes (3.6 cm internal diameter) that were inserted in the sediment to recover the top 1-cm layer. Cysts from sediments were concentrated by density separation with sodium polytungstate (2.016 g/ml).

Description: This dataset comprises new data and previously published data on marine lipid biomarkers (brassicasterol, dinosterol, C37 alkenones, and the sum of them [∑PB]) in surface suspended particles at 334 stations from seven cruises between 2010 and 2015, and in surface sediments at 258 stations from eight cruises between 2006 and 2012 in the eastern China marginal seas (ECMS). Of all marine lipid biomarker data, 107 surface suspended particle samples were newly measured, with 227 surface suspended particle samples and 258 sediment samples previously published. We also provide the following oceanographic data, most of which were collected from published results (as described in the publication): sea surface temperature (SST, n = 273, from five cruises in summer of 2010–2015), salinity (n = 273, from five cruises in summer of 2010–2015), nutrient concentrations (dissolved inorganic nitrogen [DIN], dissolved inorganic phosphorus [DIP] and silicate [Si]) (n = 133, from three cruises in summer of 2011 and 2015) and Chl a (chlorophyll a, n = 229, from five cruises in summer of 2010–2014) in the surface water, as well as terrestrial biomarker [∑(C27 + C29 + C31) n-alkanes] contents (n = 226), TOC (total organic carbon content, n = 200), δ13CTOC (stable carbon isotope values for TOC, n=269), and sedimentation rate (n = 220) in surface sediments. Some data were measured using in situ CTD instrument in this study: sea surface temperature and salinity in the East China Sea in June 2010 and July 2013 (n = 54), and Chl a in the Changjiang River Estuary in August 2015 (n = 33). The contents of ∑(C27 + C29 + C31) n-alkanes in the southern Yellow Sea in April 2012 (n = 32) were also newly measured. The surface suspended particle samples were obtained by filtering on Whatman GF/F filters, and the surface sediments were collected by multiple corers or stainless-steel grab samplers. Marine and terrestrial lipid biomarkers were analyzed by gas chromatograph (Agilent 6890N) according to the method in Zhao et al. 2006 (doi: 10.1016/j.orggeochem.2005.08.022) and Wu et al. 2016 (doi: 10.1002/2015JG003167). The study resulting from this analysis has been published in Frontiers in Marine Science (doi:10.3389/fmars.2022.824181).

Description: References of the studies in which b has been calculated from Ɛp values from alkenones, together with the coordinates, in-situ and estimated (if in-situ was not available) [CO2]aq, PO43-, SST, PAR and modeled coccolithophore growth rate using the global model [Krumhardt et al., 2017]. Interpolated micropaelontological datasets to the locations of the surface sediment samples: planktonic foraminifera intermediate-surface ratio, relative abundance of Florisphaera profunda and offset in d18O between shallow and deep planktonic foraminifera used in Fig. 8. Calculations of the required growth rate and residuals of the pruned model (CO2aq + size) (Fig. 9).

Description: Snow-cores KF13, KF14, KF15, KF16, KF17, KF18, and KF20 continuously analyzed by Continuous Flow Analysis between April and October 2019 at the Alfred-Wegener-Institut Helmholtz-Zentrum für Polar-und Meeresforschung, in Bremerhaven, Germany. All cores were sampled along the trench T15-1 in 2014/15, correspond to depths 240-340cm and are 5 meters spaced (relative distance to the starting coordinate). Isotopic measurements were realized by CRDS (Cavity-Ring-Down Spectroscopy, L-2140-i, Picarro Inc.).

Description: Discrete samples at 22mm depth-resolution for snow-cores KF13, KF14, KF15, KF16, and 33mm depth-resolution for snow-core KF20, analyzed in 2019 at the Alfred-Wegener-Institut Helmholtz-Zentrum für Polar-und Meeresforschung, in Bremerhaven, Germany. All cores were sampled along the trench T15-1 in 2014/15, correspond to depths 240-340cm and are 5 meters spaced (relative distance to the starting coordinate). Isotopic measurements realized by CRDS (Cavity-Ring-Down Spectroscopy, L-2120-i and L-2140-i, Picarro Inc.).

Description: 3D reflection seismic data were acquired using the P-Cable system of the National Oceanographic Centre, Southampton, UK during cruise 178 Leg 2 onboard RRS Charles Darwin between the 5th and 8th of April 2006. The responsible PI's was C. Berndt, Southampton Oceanography Centre, Southampton, UK. The aim of this cruise was to map submarine landslides on the eastern slopes of the Eivissa Channel, western Mediterranean Sea located between the islands of Ibiza-Formentera and the Spanish mainland. Berndt et al. (2012) used the acquired data to study repeated slope failure linked to fluid migration, while Lafuerza et al. (2012) studied geotechnical aspects of slope stability using this as additional data. Acquisition parameters: The source during seismic acquisition consisted of four 40 in3 Bolt 600B air guns spaced 0.75 m apart and tower at a depth of 1.5 m about 20 m behind the stern of the vessel (Berndt et al., 2012). The air guns are fitted with wave shape kits that emit approximately 10 in3 of air prior to the main volume to reduce the bubble pulse. The air pressure is 2000 psi, and the gun controller triggers the guns to figure every 7 seconds. The data were collected with 11 single-channel analogue streamers that were towed 10 m apart. The seismic cube in the Eivissa Channel covers an area of ca. 14 km2 (ca. 6.4 EW x 2.2 NS km) located at 306091.83 4280497.41; 305951.42 4278353.92; 312321.94 4277936.57 in UTM zone 31N. 3D seismic processing: Data were frequency filtered from 45 to 220 Hz and binned at 10 m bin interval before a Stolt time migration with a migration velocity of 1500 ms-1 was carried out. The resolution of the data is approximately 5-6 m vertically and for the 10 m inline and crossline spacing the horizontal resolution is 10-15 m (Berndt et al., 2012). Seismic data acquisition was performed between 10:05 PM on the 5th of April until 08:30 PM on the 7th of April 2006 (CD178 cruise report). The seismic cube is located at water depths of 550 to 825 m from east to west. Raw data is available here:doi:10.1594/PANGAEA.943523.

Description: 3D reflection seismic data were acquired using the P-Cable system of the National Oceanographic Centre, Southampton, UK during cruise 178 Leg 2 onboard RRS Charles Darwin between the 5th and 8th of April 2006. The responsible PI's was C. Berndt, Southampton Oceanography Centre, Southampton, UK. The aim of this cruise was to map submarine landslides on the eastern slopes of the Eivissa Channel, western Mediterranean Sea located between the islands of Ibiza-Formentera and the Spanish mainland. Berndt et al. (2012) used the acquired data to study repeated slope failure linked to fluid migration, while Lafuerza et al. (2012) studied geotechnical aspects of slope stability using this as additional data. Acquisition parameters: The source during seismic acquisition consisted of four 40 in3 Bolt 600B air guns spaced 0.75 m apart and tower at a depth of 1.5 m about 20 m behind the stern of the vessel (Berndt et al., 2012). The air guns are fitted with wave shape kits that emit approximately 10 in3 of air prior to the main volume to reduce the bubble pulse. The air pressure is 2000 psi, and the gun controller triggers the guns to figure every 7 seconds. The data were collected with 11 single-channel analogue streamers that were towed 10 m apart. The seismic cube in the Eivissa Channel covers an area of ca. 14 km2 (ca. 6.4 EW x 2.2 NS km) located at 306091.83 4280497.41; 305951.42 4278353.92; 312321.94 4277936.57 in UTM zone 31N. 2D seismic processing: During seismic processing of the 3D dataset significant ghost-artefacts were identified because some of the streamers were towed too deep. This required de-ghosting. Unfortunately, these attempts did not yield improved quality of the 3D seismic data. This was mainly because the 12.5 m streamers were too short for commonly used de-ghosting technique used in the industry. To increase vertical resolution individual 2D profiles were extracted from the raw dataset. Processing steps included frequency bandpass filtering, burst noise attenuation, binning, NMO-correction, stacked, and a Stolt migration with 1520 ms-1 was applied that resulted in higher resolution 2D profiles for 85 lines and 11 streamers (channels).

Description: This dataset contains the bulk sediment parameters (total organic carbon (TOC), carbon nitrogen ratio (C/N), δ13C), lipid biomarker (branched glycerol dialkyl glycerol tetraethers (brGDGTs), crenarchaeol, long-chain diols, long-chain n-alkanes, alkenones, sterols) and palynological (dinoflagellate cysts, pollen) content of 20 surface sediments (0-2 cm) from the northern Gulf of Mexico, near the Mississippi and Atchafalaya river mouths. Samples were retrieved from three land-sea transects; (1) offshore the Mississippi river, (2) offshore the Atchafalaya river and (3) on the 20 m isobar on the Louisiana shelf, during a research cruise in February 2020. Samples were analysed on their organic carbon composition, which was divided into soil-, fluvial- and plant-derived terrestrial organic carbon, and marine produced organic carbon, to investigate if the composition and quality of the terrestrial carbon had an influence on their dispersal patterns.