cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.1594/pangaea.935883
title: Aerosol soluble chemical composition for OASIS cruise (SO234/2 & SO235), Indian Ocean, July-August 2014, determined by ion chromatography and inductively coupled plasma - mass spectrometry

description: Size segregated aerosol samples were collected during the OASIS (“Organic very short lived substances and their Air Sea Exchange from the Indian Ocean to the Stratosphere”) cruises (FS Sonne, SO234-2 & SO235) during 8 - 20 July & 23 July – 7 August 2014 in the southern Indian Ocean (~30 E - 75 E, 30 S – 5 N). The samples were collected by Birgit Quack of GEOMAR, Kiel, Germany. The aerosol sampler was situated on the roof of the ship's wheelhouse and was connected to an automatic wind sector controller to prevent contamination of the samples from the ship's stack. Most samples were collected using a Sierra-type cascade impactor to separate the aerosol particles at an aerodynamic diameter cutoff of 1 µm. Collection time for these samples varied between 27.7 and 46.9 hours. For one sample, 6 impactor stages and a backup filter were used to give more detailed information aerosol size distribution. This sample was collected over 91.7 hours. Samples were extracted with ultrapure water and the major ions Na+, NH4+, Mg2+, K+, Ca2+, Cl-, NO3-, SO42-, oxalate, Br- and methanesulfonate were determined by ion chromatography (IC). Total soluble iodine (TSI) was determined by inductively coupled plasma - mass spectrometry (ICP-MS) and iodide (I-) and iodate (IO3-) were determined by IC-ICP-MS. The dataset contains the atmospheric concentrations of all measured soluble major ions (in nmol/m³) and iodine species (in pmol/ m³).
description: Sampler Flow: 1 m³/minSubstrate Type: Glass FibreSubstrate Pretreat: Washed in ultrapure water and then ashed at 450C for 4 hoursSize Seg Method: Sierra type cascade impactor. For most samples stages 3 and 4 were used and combined during analysis to give a fraction with aerodynamic diameter &gt; 1 µm (Size_fraction 3-4). Backup filter collected the &lt; 1µm fraction (Size_fraction w). Stages 1-6 and backup (w) filter were used an analysed separately for sample 10.Method Publication: Yodle and Baker, Atmospheric Environment X, 1, 100009, (2019).DL Value: Where the detection limit applies, concentrations are quoted as less than the limit of detection; Example atmospheric detection limits (given in Comment below) have been calculated from analytical detection limits for an air volume of 2500 m³.
DOI: 10.1594/pangaea.938692
title: High variability in SSU rDNA gene copy number among planktonic foraminifera revealed by single-cell qPCR

description: Metabarcoding has become the workhorse of community ecology. Sequencing a taxonomically informative DNA fragment from environmental samples gives fast access to community composition across taxonomic groups, but it relies on the assumption that the number of sequences for each taxon correlates with its abundance in the sampled community. However, gene copy number varies among and within taxa, and the extent of this variability must therefore be considered when interpreting community composition data derived from environmental sequencing. Here we measured with single-cell qPCR the SSU rDNA gene copy number of 139 specimens of five species of planktonic foraminifera. We found that the average gene copy number varied between of ~4 000 to ~50 000 gene copies between species, and individuals of the same species can carry between ~300 to more than 350 000 gene copies. This variability cannot be explained by differences in cell size and considering all plausible sources of bias, we conclude that this variability likely reflects dynamic genomic processes acting during the life cycle. We used the observed variability to model its impact on metabarcoding and found that the application of a correcting factor at species level may correct the derived relative abundances, provided sufficiently large populations have been sampled.
description: Supplementary Material 1. Geographic origin, taxonomic identification and SSU rDNA gene copy number quantification obtain with qPCR for the 139 specimens. Sequences are provided for the fragment 45E-47F.
DOI: 10.1594/pangaea.938700
title: Bacterial biomass production measured in water samples of POLARSTERN cruise PS111 (ANT-XXXIII/2)

description: Global warming poses new threats to marine ecosystems since rising seawater temperature potentially induces cascading effects in biogeochemical cycles and food webs. Heterotrophic bacteria are the main producers of CO2 in the ocean, thereby counteracting the biological drawdown of CO2 by primary production. In Antarctic marine systems, low seawater temperature, and the low availability of labile organic matter are major environmental constraints on bacterial growth and degradation activity. However, temperature and the availability of resources for heterotrophic bacteria undergo considerable change induced by climate warming combined with subsequent ice melt and changes in primary productivity. This project aims to test single and combined effects of temperature and organic matter availability on Antarctic marine bacterioplankton. This data set includes measurements on bacterial biomass production at 0°C and 3°C measured alongside the CTD casts during the Polarstern cruise PS111 to the Weddell Sea. Samples were collected in the upper 100 m of the water column at the Eastern Weddell Sea Shelf and at the Filchner-Ronne ice shelf.
DOI: 10.1594/pangaea.938702
title: Dissolved organic matter, chlorophyll a and bacterial abundance measured in water samples of POLARSTERN cruise PS111 (ANT-XXXIII/2)

description: Global warming poses new threats to marine ecosystems since rising seawater temperature potentially induces cascading effects in biogeochemical cycles and food webs. Heterotrophic bacteria are the main producers of CO2 in the ocean, thereby counteracting the biological drawdown of CO2 by primary production. In Antarctic marine systems, low seawater temperature, and the low availability of labile organic matter are major environmental constraints on bacterial growth and degradation activity. However, temperature and the availability of resources for heterotrophic bacteria undergo considerable change induced by climate warming combined with subsequent ice melt and changes in primary productivity. This project aims to test single and combined effects of temperature and organic matter availability on Antarctic marine bacterioplankton. This data set includes biological and biogeochemical parameters measured alongside the CTD casts during the Polarstern cruise PS111 to the Weddell Sea. Samples were collected in the upper 100 m of the water column at the Eastern Weddell Sea Shelf and at the Filchner-Ronne ice shelf. Concentrations of different components of dissolved organic matter and inorganic nutrients as well as chlorophyll a concentrations and bacterial cell numbers are reported.
DOI: 10.1594/pangaea.937415
title: Age determination of sediment cores from METEOR Cruise M75/3
DOI: 10.1594/pangaea.937420
title: Mg/Ca ratio from Globigerinoides ruber white of sediment cores from METEOR Cruise M75/3
DOI: 10.1594/pangaea.937421
title: Reconstructed sea surface temperature (SST) by Mg/Ca and oxygen isotope time-series of local mixed layer from METEOR Cruise M75/3
DOI: 10.1594/pangaea.937422
title: W-E gradient reconstructed sea surface temperature (SST) by Mg/Ca and oxygen isotope time-series of local mixed layer from METEOR Cruise M75/3
DOI: 10.1594/pangaea.939237
title: Methane and ethane concentrations and carbon isotopic compositions in gas-rich sediments measured of the Gulf of Cadiz in 2020

description: Here we measured the concentrations and carbon isotopic composition of methane and ethane in sediment cores from several gas-rich sites in the Gulf of Cadiz. The aim of this sampling was to reveal the fate of both gases within the sediment in relation to the consumption of sulfate (Anaerobic oxidation of methane) and to measure isotope effects of this process on the carbon isotopic compositions. Therefore, sediment samples were collected during Meteor expedition M167 in October 2020 by gravity coring. After recovery, the core was cut into 1 m sections that were vertically split into an archive and a working half. Directly after this, defined volumes of 2 ml sediment were samples with cut-off syringes and transferred into 20 ml vials filled with 5 ml NaOH (1M) solution. Vials were immediately sealed with butyl septa and crimps. Methane and ethane concentrations were measured by gas chromatography coupled to flame ionization detection. Carbon isotopic composition of methane and ethane were measured as isotopomers of CO2 produced from these gases by in-line combustion coupled to isotope ratio mass spectrometry. Both methane and ethane were consumed with the consumption of methane. Methane isotopic composition was strongly altered in these zones. By contrast, isotope values of ethane remained rather stable.
description: Methane and ethane concentration measurements: 2 ml sediment sampled into 5 ml NaOH in 20 ml crimp vials, Methane concentration was measured using gas chromatography coupled to flame ionization detection (Agilent7820A GC with a Carboxen 1010 PLOT column, oven temperature 60°C for 2 min; gradient 25°C min-1 to 160°C for 3 min).Methane and ethane carbon isotopic composition was determined using in line combustion to CO2 with a Thermo Finnigan Trace GC and Alltech AT-Q column (30m x 0.32mm length internal diameter, 0.32 mm, carrier gas He); column temperature setting: 2min 40°C for 2 min, gradient 40°C min to 240°C, hold for 3 min) coupled via GC Combustion III interface (940°C) to Thermo Delta plus X ratio mass spectrometer.
DOI: 10.1594/pangaea.939249
title: Physical oceanography from mooring KPO_1215

description: GEOMAR moorings are typically equipped with instruments recording pressure, temperature, conductivity, dissolved oxygen and current velocity. Instruments with pressure, temperature, conductivity and oxygen sensors were calibrated in situ immediately prior to and after a mooring deployment period by attaching them to the CTD frame during CTDO casts. Correction terms were then developed from the difference between the sensor readings and the calibrated CTDO data during several minute long calibration stops. These correction terms were then applied to the full deployment periods. This ensured best data quality with recognition of potential sensor drifts and also allowed for the estimation of calibration and measurement errors (Hahn et al. 2014, Bittig et al. 2018, Berx et al. 2019).
description: instrument = Label:kpo_1215_02 File:kpo_1215_instr_02.nc Type:Seabird MicroCat 37-IM mit P SN:10654instrument = Label:kpo_1215_03 File:kpo_1215_instr_03.nc Type:Aanderaa Optode 3830 SN:01160 depth/pressure data was at least partially derived and not directly measured, consult quality flags for detailsinstrument = Label:kpo_1215_05 File:kpo_1215_instr_05.nc Type:Teledyne RDI LongRanger 75 SN:17570instrument = Label:kpo_1215_06 File:kpo_1215_instr_06.nc Type:Seabird MicroCat 37-IM mit P SN:10655instrument = Label:kpo_1215_07 File:kpo_1215_instr_07.nc Type:Aanderaa Optode 3830 SN:01141 depth/pressure data was at least partially derived and not directly measured, consult quality flags for detailsinstrument = Label:kpo_1215_08 File:kpo_1215_instr_08.nc Type:Sontek Argonaut SN:187 depth/pressure data was at least partially derived and not directly measured, consult quality flags for detailsinstrument = Label:kpo_1215_09 File:kpo_1215_instr_09.nc Type:Seabird MicroCat 37-SM SN:00936 depth/pressure data was at least partially derived and not directly measured, consult quality flags for detailsinstrument = Label:kpo_1215_10 File:kpo_1215_instr_10.nc Type:Sontek Argonaut SN:294 depth/pressure data was at least partially derived and not directly measured, consult quality flags for detailsinstrument = Label:kpo_1215_11 File:kpo_1215_instr_11.nc Type:Seabird MicroCat 37-IM mit P SN:02265instrument = Label:kpo_1215_12 File:kpo_1215_instr_12.nc Type:Sontek Argonaut SN:304 depth/pressure data was at least partially derived and not directly measured, consult quality flags for detailsinstrument = Label:kpo_1215_13 File:kpo_1215_instr_13.nc Type:Seabird MicroCat 37-SM SN:01285 depth/pressure data was at least partially derived and not directly measured, consult quality flags for detailscomment = flag_meaningscomment = 0:unknowncomment = 1:good_datacomment = 2:probably_good_datacomment = 3:potentially_correctable_bad_datacomment = 4:bad_datacomment = 5:not_usedcomment = 6:not_usedcomment = 7:nominal_valuecomment = 8:interpolated_valuecomment = 9:missing_value
DOI: 10.1594/pangaea.939691
title: Age model of sediment core MD95-2042
DOI: 10.1594/pangaea.939844
title: Radiocarbon data of bulk organic carbon from sediment core HLY1302-JPC15
DOI: 10.1594/pangaea.940549
title: Base of productive zone of N. pachyderma during cruises ARK-IV/3, ARK-XI/1, ARK-XIII/2, ARK-XV/1, ARK-XV/2, M21/4, M21/5, M39/4, MSM44, MSM66, MSM09/2, NEWP-92, NEWP-93, PS93.1, PS31, PS78

description: Based on shell concentrations of the planktonic foraminifera Neogloboquadrina pachyderma from vertically resolved plankton tow samples during cruises ARK-IV/3, ARK-XI/1, ARK-XIII/2, ARK-XV/1, ARK-XV/2, MSM44, MSM66, M21/4, M21/5, M39/4, MSM09/2, NEWP-92, NEWP-93, PS93.1, PS31, PS78, the base of the productive zone is calculated. The calculation is based on the assumption that the base of productive zone is located where shell concentration begins to substantially decline and it is calculated after Lončarić et al. (2006).
description: The calculation of the base of the productive zone of N. pachyderma is based on the assumption that the base of productive zone is located where shell concentration begins to substantially decline, which was determined visually. For all cases in which abundances decrease with depth, it is calculated after Lončarić et al. (2006): Z_BPZ=(C_n-C_exp)/C_(n-1) (Z_n-Z_(n-1) )+Z_(n-1)All BPZ that is based on this equation have the remark “regular” in the column of calculation method. As the equation is constructed for cases where the shell concentration decreases with depth, it cannot be applied where this is not the case (such as where there is a distinct subsurface maximum), as the estimated BPZ would appear to lie below the depth interval of the transition zone. In those cases, the BPZ was defined as the bottom depth of the transition zone (labeled as range end).
DOI: 10.1594/pangaea.940554
title: Mass flux of Neogloboquadrina pachyderma during cruises ARK-IV/3, ARK-XI/1, ARK-XIII/2, ARK-XV/1, ARK-XV/2, M21/4, M21/5, M39/4, MSM44, MSM66, MSM09/2, NEWP-92, NEWP-93, PS93.1, PS31, PS78

description: Based on shell concentrations of the planktonic foraminifera Neogloboquadrina pachyderma from vertically resolved plankton tow samples during cruises ARK-IV/3, ARK-XI/1, ARK-XIII/2, ARK-XV/1, ARK-XV/2, MSM44, MSM66, M21/4, M21/5, M39/4, MSM09/2, NEWP-92, NEWP-93, PS93.1, PS31, PS78 and (average) shell weights, the calcite mass flux is calculated (mg m-2 d¬-1).
description: Further details:The calcite mass flux is calculated after Schiebel and Hemleben (2000): Calcite mass flux (mg m-2 d^-1) = shell weight (mg) * shell concentration (ind. m^-3) * sinking velocity (m d^-1).The sinking velocity is calculated after Takahashi and Bé (1984):Foraminifera sinking velocity (m d^-1) = 10^2.06 * shell weight (µg)^0.64.Depending on the availability of shell weight data, either measured or average values where used, which are listed in the column “shell weight type” as follows:Measured average: Shell weight was measured on the shells of the samples as a bulk weight, leading to an average value for individual shells.Regional average: Based on measured values from the same sampling region, but not the same samples.Total average: Based on all measured values from the study in the Subarctic and Arctic realm, used where no measurements from the same region are present .Regional and total averages were calculated based on measurements from shells from below the productive zone, as those are the shells representing the export flux.
DOI: 10.1594/pangaea.939867
title: Oceanic surface water isotopic compositions calibrated data from POLARSTERN cruise PS94 (ARK-XXIX/3)

description: Isotopic measurements of seawater sampled on-board Polarstern research vessel
DOI: 10.1594/pangaea.939868
title: Oceanic surface water isotopic compositions calibrated data from POLARSTERN cruise PS95.1 (ANT-XXXI/1.1)

description: Isotopic measurements of seawater sampled on-board Polarstern research vessel
DOI: 10.1594/pangaea.939869
title: Oceanic surface water isotopic compositions calibrated data from POLARSTERN cruise PS95.2 (ANT-XXXI/1.2)

description: Isotopic measurements of seawater sampled on-board Polarstern research vessel
DOI: 10.1594/pangaea.939870
title: Oceanic surface water isotopic compositions calibrated data from POLARSTERN cruise PS96 (ANT-XXXI/2)

description: Isotopic measurements of seawater sampled on-board Polarstern research vessel
DOI: 10.1594/pangaea.939872
title: Oceanic surface water isotopic compositions calibrated data from POLARSTERN cruise PS98 (ANT-XXXI/4)

description: Isotopic measurements of seawater sampled on-board Polarstern research vessel
DOI: 10.1594/pangaea.939873
title: Oceanic surface water isotopic compositions calibrated data from POLARSTERN cruise PS99.1

description: Isotopic measurements of seawater sampled on-board Polarstern research vessel
DOI: 10.1594/pangaea.939877
title: Oceanic surface water isotopic compositions calibrated data from POLARSTERN cruise PS101

description: Isotopic measurements of seawater sampled on-board Polarstern research vessel
DOI: 10.1594/pangaea.939878
title: Oceanic surface water isotopic compositions calibrated data from POLARSTERN cruise PS102

description: Isotopic measurements of seawater sampled on-board Polarstern research vessel
DOI: 10.1594/pangaea.939879
title: Oceanic surface water isotopic compositions calibrated data from POLARSTERN cruise PS103

description: Isotopic measurements of seawater sampled on-board Polarstern research vessel
DOI: 10.1594/pangaea.939881
title: Oceanic surface water isotopic compositions calibrated data from POLARSTERN cruise PS105

description: Isotopic measurements of seawater sampled on-board Polarstern research vessel
DOI: 10.1594/pangaea.939882
title: Oceanic surface water isotopic compositions calibrated data from POLARSTERN cruise PS106

description: Isotopic measurements of seawater sampled on-board Polarstern research vessel
DOI: 10.1594/pangaea.939883
title: Lowered ADCP data during METEOR cruise M148/1

description: LADCP measurements from METEOR cruise M148/1 used a two-instrument configuration with two Teledyne RDI 300 kHz workhorse ADCPs mounted in down- and up-looking positions. Data collection and processing was performed according to recommendations in the GO-SHIP manual (Thurnherr et al., 2010).
DOI: 10.1594/pangaea.940842
title: d18O and paleoproxies from sediment core M77/2_024-5

description: This dataset includes δ 18O measurements, depth-age relationship, Uk'37 values, two records of ocean temperatures (alkenone and TEXH86), the difference between these two temperatures and d15N values measured on sediment core M77/2-024-5. Sediment core M77/2-024-5 (11°05.01'S; 78°00.91'W) was collected at 210 meters depth off Peru during Meteor expedition M77/2 in 2008 (Meteor station No. M772/677). To better constrain the age model for the last interglacial in core M77/2-024-5, 49 samples between 1093 to 1388 cm depth were selected and at least 10 specimens of Bolivina seminuda, that did not show signs of degradation or alteration, were carefully picked for the δ18O record. Oxygen isotope measurements were performed at the Leibniz Labor, Christian-Albrechts-University, Kiel. The δ18O record was used to construct the depth-age relationship shown in this dataset. According to the age model developed, core M77/2-024-5 covers the last 142 kyr BP. Water column denitrification was inferred through δ15N measurements of sedimentary organic matter. Core M77/2-24 was subsampled every 5 cm, from 1093 to 1478 cm, for δ15N analysis. The precision of the isotopic analyses was ±0.25‰. In order to estimate ocean temperatures, alkenones were measured at the Institute of Geosciences in Kiel, Germany. The UKˈ37 was calculated as C37:2 / (C37:2 + C37:3), where C37:2 (C37:3). Core M77/2-24 was subsampled every 5 cm for alkenone measurements. Finally, seventy-one samples were analyzed to reconstruct ocean water temperatures using the TEXH86. The temperature difference between the UKˈ37 and the TEX86 can be attributed to changes in water column stratification, with higher offsets interpreted to indicate a deeper thermocline.
DOI: 10.1594/pangaea.940843
title: Fish vertebrae widths and preservation index of sediment core M77/2_024-5

description: This dataset includes the average and standard deviation of the width of fish vertebrae, the number of observations per sample and a preservation index of fish vertebrae obtained from core M77/2-024-5. Sediment core M77/2-024-5 (11°05.01'S; 78°00.91'W) was collected at 210 meters depth off Peru during Meteor expedition M77/2 in 2008 (Meteor station No. M772/677). The measurements of the vertebrae widths were determined in 60 samples along core M77/2-024-5 from 1093 to 1388 cm depth corresponding to 110.7 to 137.8 kyr BP. The widths of the complete vertebrae per sample were measured and the average per sample is presented in this dataset. The preservation index of fish vertebrae estimates the surface of the vertebrae that is not affected by bio-erosion. This index was calculated per each vertebra, and ranges from 1 to 4. An average per sample interval was done to calculate the biodegradation index where higher values indicate better preservation of the fish vertebrae remains.
DOI: 10.1594/pangaea.940844
title: Fish debris abundance and fluxes in sediment core M77/2_024-5

description: This dataset includes fish vertebrae abundances and fluxes obtained from core M77/2-024-5. Sediment core M77/2-024-5 (11°05.01'S; 78°00.91'W) was collected at 210 meters depth off Peru during Meteor expedition M77/2 in 2008 (Meteor station No. M772/677). Fish debris quantification and identification were determined in 60 samples along core M77/2-024-5 from 1093 to 1388 cm depth corresponding to 110.7 to 137.8 kyr BP. Sediment samples consisted of an average of 41 g of wet material, which yields 16.3 g of dry sediment. The fish vertebrae identification includes the following species/groups: anchovy (Engraulis ringens), goby-like fishes, juvenile fishes, Vinciguerria lucetia, hake (Merluccius gayi peruanus), blue lanternfish (Tarletonbeania crenularis), eel-shaped fish and other unidentified species. The fish debris were quantified and identified with the help of scale and vertebrae collections. The fish debris fluxes (#debris × cm−2 × y-1) were calculated by multiplying the fish debris abundance (number of fish debris x g-1) by the sedimentation rates (cm x y-1) by the dry bulk density (g x cm-3). Finally, the fluxes were multiplied by 1000.