ALBERT

Description: Underway optical chlorophyll-a and turbidity data were collected along the cruise track with Sea-Bird Scientific ECO FLNTU sensors installed within two autonomous measurement systems, called self-cleaning monitoring boxes (SMBs). The SMBs measure alternatingly. While one box is measuring, the other one is being cleaned. At the beginning of the transect, the boxes switched to operation every three hours, later, while the ship is transecting the Pacific Gyre, the cleaning interval was changed to only every 24 hours. The water inlet for the SMBs is at about 4 m depth. The data were quality controlled and the chlorophyll-a data were additionally calibrated using discrete water samples. In situ chlorophyll-a samples were collected by the scientific party from Niskin bottles during CTD stations and underway using a tow fish. Chlorophyll-a of these samples was determined in the lab on board using a bench top fluorometer. Details on all quality control steps, the calibration, as well as a comparison to satellite data can be found in the data processing report. The resulting data set contains the original data and corresponding quality flags and, in case of chlorophyll-a, additionally the calibrated data plus quality flag. The data source is given through the name of the active SMB. The data set contains data during transect and station. We recommend to use ship's speed to filter for only transect data.

Description: High-resolution multi-proxy records from two lakes on the southern Tibetan Plateau, Nam Co and Tangra Yumco, are used to infer long-term variations in the Asian monsoon system. We examine the moisture evolution during the Late Glacial Maximum and Holocene using the trace element and stable isotope composition of ostracod shells. The sediment records covering the past 24 cal. ka BP and 18 cal. ka BP, respectively, demonstrate the suitability of ostracod shell chemistry as paleoenvironmental proxy. We analysed (i) Mg/Ca, Ba/Ca and Sr/Ca ratios as salinity proxies, (ii) Fe/Ca, Mn/Ca and U/Ca ratios representing redox conditions and microbial activity, and (iii) rare earth elements (REEs) reflecting weathering and changes in provenance.

Description: This dataset presents benthic foraminiferal δ¹⁸O chronostratigraphies for International Ocean Discovery Program (IODP) Site U1541, Ocean Drilling Program (ODP) Site 1090 and ODP Site 980-981 based on different tuning targets including LR04 (Lisiecki and Raymo, 2005), LR09 (Lisiecki and Raymo, 2009), CENOGRID (Westerhold et al., 2020) and Probstack (Ahn et al., 2017) obtained by Middleton et al. (2024). The benthic foraminiferal δ¹⁸O record for IODP Site U1541 (54°13'S, 125°25'W) recently recovered from the central South Pacific on IODP Expedition 383 (Winckler et al., 2021) is shown for the first time and is published in Middleton et al. (2024). All data records are based on Cibicidoides wuellerstorfi and Cibicides kullenbergi, or combinations thereof. The dataset provides the basis for investigating and discussing the uncertainties of benthic foraminiferal δ¹⁸O stratigraphies for conventional manual and automated tuning techniques and evaluate their impact on sedimentary age models over the past 3.5 Myr (Middleton et al., 2024).

Description: In July 2022 within the framework of an Alfred-Wegener-Institute-managed expedition and the Nunataryuk project, sediment cores were taken at three locations, off the coast of Herschel Island, Canada, using a hand corer: YC22_MR_6: 69°34'23.12N, 138°54'37.76W; 3 m water depth; July 6th 2022 YC22_MR_7: 69°34'23.53N, 138°56'37.66W, 6 m water depth; July 7th 2022 YC22_MR_8: 69°30'22.75''N, 138°53'21.69''W; 45 m water depth; July 24th 2022 Data sets were obtained to investigate carbon feedback from the sediments to the water column and atmosphere, using DIC concentrations and isotopic values. The local sediments are supplied primarily by organic carbon previously stored in adjacent permafrost soils (biomarker and bulk data), which erode and redeposit quickly (age model) on the ocean floor. The acquired data includes: 1) Sediment data: Bulk total organic carbon content (Lamping et al., 2021) and its isotopic values for 13C (Brodie et al., 2011; Werner & Brand, 2001) and 14C (Mollenhauer et al., 2021) and Biomarker data: Quantifying alkanes (CPI) , and fatty acids (TAR ratio) as described by Wei et al. (2020), Glycerol dialkyl glycerol tetraethers (GDGTs basis for BIT-Index) after Hopmans et al. (2016), Hopanes (fßß) following instructions by Meyer et al., (2019), and Sterols (Dinosterol) after Dauner et al. (2022). 2) Porewater was extracted from the cores using rhizomes and quantified as described in Oni et al., (2015). Dissolved inorganic carbon isotope signatures were determined as CO2 for 13C (Torres et al., 2005) and 14C (Mollenhauer et al., 2021). 3) Intact polar lipid fatty acids were extracted from the sediments, purified, and 14C analysis was performed as described in Ruben et al. (2023). The 13C isotopy was determined with GC-IRMS (Elvert et al., 2003). The respective precursor lipids of the polar fraction used for isotope analysis were quantified following the method described in Wörmer et al. (2013). Datasets are to be found at doi:10.1594/PANGAEA.966262 and doi:/10.1594/PANGAEA.966264. 4) Sedimentary age model of core YC22_MR_7 assuming constant rate of supply (CRS) model (Appleby, 2001), based on data obtained with a HPGe gamma detector.

Description: We present results of Th/U dating, stable isotope and trace element data from a speleothem from Puerto Rico. Th/U dating was performed using isotope dilution MC-ICPMS. Activity ratios were corrected for initial Th assuming an detrital weight ratio 232Th/238U = 0.154 ± 0.038 (corresponding to an activity ratio of the detritus in secular equilibrium of (230Th/232Th)detr = 19.79 ± 4.93), and secular equilibrium of the detritus. Ages are calculated using the decay constants by Cheng et al. (2000)). Uncertainties are given as 2σ- range, and do not include half-life uncertainties. Th/U dating shows that stalagmite PR-LA-1 covers the period from 15.4 to 46.2 ka with a growth interruption between 35.5 and 41.1 ka. Stable isotope samples were drilled with a spatial resolution of 1 mm and measured using an IRMS equipped with a Gasbench. Element/Calcium ratios of the speleothem were measured by laser ablation ICPMS and were reduced to the resolution of the stable isotope records.

Description: We present a new speleothem trace element and stable isotope record, which extends previous paleoclimate evidence from Cuban speleothems to the last 96 ka. Stable isotope samples were micromilled at a resolution of 0.10-0.33mm, and measured using an IRMS equipped with a Gasbench. Line scans of Element/Calcium ratios of the speleothem were measured by laser ablation ICPMS and were reduced to the resolution of the stable isotope records.

Description: We present a new speleothem trace element and stable isotope record, which extends previous paleoclimate evidence from Cuban speleothems to the last 96 ka. Stable isotope samples were micromilled at a resolution of 0.10-0.33mm, and measured using an IRMS equipped with a Gasbench. Line scans of Element/Calcium ratios of the speleothem were measured by laser ablation ICPMS and were reduced to the resolution of the stable isotope records.

Description: Culturing experiments exposed the scleractinian corals Porites lobata and Porites lichen to a mixture of dissolved chromium (Cr), manganese (Mn), nickel (Ni), copper (Cu), zinc (Zn), silver (Ag), cadmium (Cd), tin (Sn), mercury (Hg) and lead (Pb) in a wide concentration range for a period of more than a year. The aim was to examine whether the incorporation of heavy metals into the aragonitic skeleton of the corals is a direct function of their concentration in seawater. Therefore, the trace-element-to-calcium ratio (TE/Ca) in the coral aragonite precipitated during culturing was measured by Laser ablation ICP-MS in 2020. The measurement showed that all metals used here were measureable in the coral skeleton and only minor, non-systematic intra- and interspecies differences in the trace metal concentrations was found. A positive correlation between the TE/Ca values and the coral skeleton was found for Cr, Mn, Ni, Zn, Ag, Cd and Pb. Cu, Sn and Hg did not show any clear trend. This dataset shows time resolved trace element-to-calcium values of coral colonies A to D cultured in the metal system along the measured Laser ablation ICP-MS scanning lines (Line XY stands for different Laser ablation lines measured at different positions at one respective coral colony) and values derived from the composite lines. Measurements were carried out from the top of the coral to the bottom and the distance starting from the top is indicated as “Elapse Time”. The energy density of the laser was set to 10 J/cm3, the laser spot size was 120 µm diameter and the stage moved 50 µm/s. Prior to every scan, a preablation pass with a spot size of 160 µm diameter was carried out to clean the cut surface of the coral skeleton. Culturing experiments were configured with two identically experimental aquaria. Four different coral colonies and two different species were used (Porites lobate Coral A-C, Porites lichen Coral D). All colonies were divided into subcolonies and growth control was performed with Alizarin Red S prior and during the experiment. One subcolony was placed in each experimental tank. The control aquarium remained unmodified while the trace metal concentration in the metal aquarium was elevated stepwise (Phase 1-4, Phase 1 = lowest metal concentration). The trace metal concentration in both tanks was monitored during the culturing period. After the experiment and more than 15 months later, specimens were cut again and the trace metal concentration in the coral skeleton was determined. It should be noted that coral D died 2.5 weeks after the exposure to the highest metal concentration in phase 4. TE/Ca values are processes as followed: (1) Time resolves raw intensities (in counts per seconds) for all isotopes measured were processed with the software Iolite (Version 4). The determination of element/Ca ratios was performed after the method of Rosenthal et al. (1999). High values of 25Mg, 27Al or 55Mn at the beginning of an ablation profile were related to contamination on the surface of the coral or remains of organic matter and these parts of the profiles were excluded from further data processing. (2) The NIST SRM 612 glass (Jochum et al., 2011) was used for monitoring and correction of the instrument drift. (3) The detection limit was defined by 3.3*SD of the gas blank in counts per seconds for every element in the raw data. Only values above this limit were used for further analyses and no data below the LOQ (limit of quantification = 10*SD) were interpreted. After processing the data with Iolite, an outlier detection of the TE/Ca ratios of the samples was performed. If trace metal values from deviated more than ±2SD from the average of the samples from the corresponding culturing phase, values were defined as outliers and discarded. (4) A composite line was calculated individually for all colonies consisting of the laser ablation measurements along the main growth axis of the coral (coral A line 1-3, coral B line 1-3, coral C line 2 + 3, coral D line 1). Laser ablation measurements along lines that were deviating from the main growth axis of the coral were not taken into account. Calculations were performed with QAnalyseries (Kotov and Paelike, 2018).

Description: For trace element analyses, single specimens of C. wuellerstorfi have been analyzed using femtosecond laser ablation inductively coupled plasma mass spectrometry (fs-LA-ICP131 MS) at the Geochemistry Laboratory at the Max Planck Institute for Chemistry. Na, Mg, and Sr of 142 specimens of C. wuellerstorfi have been measured at high-resolution on (up to) each of the final five chambers to eliminate possible inaccuracies that are likely to be caused by varying sample size. The fs-LA-ICP-MS analyses were performed on 25-μm diameter spots on each chamber with a pulse repetition rate of 15 Hz at low fluence (0.1-0.3 J/cm2). Calibration was performed with the microanalytical synthetic reference material MACS‐3 for carbonate and NIST612 for silica. Average values of all chambers analyzed in the same specimen were used for further analyses. Since foraminifers from different regions show particular offsets in the Mg/Ca composition of their shell, depending on region specific temperature ranges of ambient seawater, region-specific formulas are used. We have applied the formula Mg/Ca=0.82e^0.19*BWT of Tisserand et al. (2013) from samples collected from similar geographic situations to avoid offsets. The formula has been applied to calculate temperature variability of each analyzed chamber. The average value obtained from chamber-to-chamber temperature variability of each specimen has been applied as average temperature data of the entire test.

Description: Here, we present a global compilation of previously reported sightings of the rare planktic foraminifer Globorotalia cavernula Bé, 1967 as well as new observations of live-collected specimens from the Southern Ocean (Subantarctic south of Africa). The goal of this synthesis is to provide the geographic and stratigraphic context needed to investigate the past and present-day distributions of this rare but possibly under-recognized species. The previous records include modern occurrences in the water column (collected by plankton net tows and a single sediment trap) and seafloor sediments ranging in age from recent to Eocene. Seafloor sediment samples were collected by dredge, sediment grabs and core-tops. Deeper sediments came from drilling cores. Existing databases provided a foundation for this compilation, particularly ForCenS for surface sediments (Siccha & Kucera, 2017) and FORCIS for water-column collections (de Garidel-Thoron et al., 2022; Chaabane et al., 2022, 2023). These records were supplemented with occurrences from the literature, PANGEA, and cruise reports of the Deep Sea Drilling Project (DSDP) / Ocean Drilling Program (ODP). Searches were conducted in October 2022 using Google Scholar, GBIF, EOL (Encyclopedia of Life, "http://eol.org", which includes records from the Smithsonian NMNH). Where available, we include information on the abundance of G. cavernula in each collection, and indicate whether photographic evidence (or drawings) could be found to support the identification. Globorotalia crozetensis Thompson, 1973 (reclassified as G. cavernula by Brummer & Kučera, 2022) and closely related Globorotalia petaliformis Boltovskoy, 1974 were also included in compilation.