ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

You have 0 saved results.
Mark results and click the "Add To Watchlist" link in order to add them to this list.
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Articles  (69,576)
  • PANGAEA
  • MDPI Publishing
Collection
Language
  • 1
    Publication Date: 2024-04-11
    Description: This dataset reports measurements from a laboratory incubation of soils sourced from a boreal peatland and surrounding habitats (Siikaneva Bog, Finland). In August 2021, soil cores were collected from three habitat zones: a well-drained upland forest, an intermediate margin ecotone, and a Sphagnum moss bog. The cores from each habitat were taken from surface to approximately 50cm below surface using an Eijelkamp peat corer and subdivided by soil horizon. The samples were then incubated anaerobically for 140 days in three temperature treatment groups (0, 4, 20°C). Subsamples of the incubations headspace (250 µL) were measured on a gas chromatograph (7890A, Agilent Technologies, USA) with flame ionization detection (FID) for CO2 and CH4 concentrations. The rate of respiration from the samples were calculated per gram carbon and per gram soil as described in the method of Robertson., et al. (1999) and reported here, along with other relevant parameters.
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
  • 3
    Publication Date: 2023-08-25
    Description: Surface air temperature measurements obtained from different sensors are used to construct a unique time series with one minute time-interval. Apart from differences in design and environmental exposition, periods of missing data also exist in the data series of each sensor. A primary data set was selected in terms of quality and temporal extension. A combination of two different techniques is applied to complete this data set: one is based on the autocorrelation of the series and the other on measurements taken from other sensors. The resulting values constitute a complete series of surface air temperature at AGGO.
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    Publication Date: 2024-01-19
    Description: Presented are analytical data from lacustrine sediment cores, retrieved from Lake Nam Co (Tibetan Plateau). The sediment core is a composite of one gravity core, taken with a Rumohr-Meischner gravity corer (63 mm diameter) and a piston core, retrieved using an uwitec piston coring system (http://www.uwitec.at; 90 mm diameter). The composite core labelled 〈NC 08/01〉 comprises a total length of 10.378 m. The cores were obtained at N 30.737417, E 090.790333 at a water depth of 93 m on 2008-09-15. The purpose of obtaining this sediment core was to establish a high-resolution record of climate (monsoonal) and environmental change using multiple proxy data. The dataset comprises analytical data based on sedimentological, inorganic geochemical, mineralogical and isotope-geochemical methods. Specifically: sediment water content & density; magnetic susceptibility; particel size data; quantitative inorganic geochemical data (ICP-OES aqua regia and HCL digestions); semi-quantitative XRF elemental data; carbon, nitrogen, sulfur contents; qualitative mineralogical data; bulk sediment stable carbon and oxygen isotope data.
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    Publication Date: 2024-01-19
    Description: This data set is part of a larger data harmonization effort to make lake sediment core data machine readable and comparable. Here we standardized X-ray fluorescence line scanning (XRF)-based element data of sediment core EN18208, retrieved in 2018 from Lake Ilirney (Chukotka, Russia) at 10.76 m water depth. The glacial lake Ilirney is situated in the forest tundra mountain area and has one outflow, one main inflow and several smaller inflows. It lies at an elevation of ca. 428 m a.s.l. with a surface area of ca. 30 km2 and a maximum lake water depth of estimated 44 m. The 10.76 m sediment core was retrieved by a UWITEC piston corer during the RU-Land_2018_Chukotka expedition of the Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research (AWI, Germany, Potsdam) in cooperation with the North Eastern Federal State University (NEFU, Russia, Yakutsk). The downcore elemental composition was measured using an AVAATECH x-ray fluorescence core scanner at Bundesanstalt für Geowissenschaften und Rohstoffe (BGR) in Berlin, Spandau.
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    Publication Date: 2024-01-19
    Description: This data set is part of a larger data harmonization effort to make lake sediment core data machine readable and comparable. Here we standardized radiocarbon and OSL age data of sediment core EN18208, retrieved in 2018 from Lake Ilirney (Chukotka, Russia) at 10.76 m water depth. The glacial lake Ilirney is situated in the forest tundra mountain area and has one outflow, one main inflow and several smaller inflows. It lies at an elevation of ca. 428 m a.s.l. with a surface area of ca. 30 km2 and a maximum lake water depth of estimated 44 m. The 10.76 m sediment core was retrieved by a UWITEC piston corer during the RU-Land_2018_Chukotka expedition of the Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research (AWI, Germany, Potsdam) in cooperation with the North Eastern Federal State University (NEFU, Russia, Yakutsk). Radiocarbon data have been analysed from bulk sediment samples in Bremerhaven at the MICADAS laboratory. Optically stimulated luminescence (OSL) dating was performed at the Royal Holloway Luminescence Laboratory using a Risø TL/OSL-DA-15 automated dating system.
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    Publication Date: 2024-01-19
    Description: A 25-cm long predominantly aragonite stalagmite was collected November 2, 2005 from Dharamjali Cave (29.5°N, 80.2°E) in the central Himalayas. This dataset contains stable isotope, trace element, XRF, U/Th dating, and dripwater data. The age model spans 4.2 to 2.3 ka BP, and the dataset records seasonal shifts in hydroclimate from 4.2 to 3.1 ka BP. Using the DHAR-1A half of the speleothem, 750 samples were milled at 100–300 µm resolution for stable isotope analysis (δ18O and δ13C) and analyzed at GFZ Potsdam. Further high-resolution stable isotope analysis at the University of Cambridge included 876 samples from the bottom 4 cm of the mirroring slab DHAR-1B, covering c. 4.2–3.6 ka BP. The δ44/40Ca measurements were made on 60 aragonite samples of aragonite and 1 calcite sample milled between 4.2 and 2.8 ka BP. The elemental composition of DHAR-1B was determined first with an Avaatech XRF scanner at the University of Cambridge, and later using laser ablation inductively-coupled plasma mass spectrometry (LA-ICP-MS) at the University of Waikato. U-series dating was performed at Caltech on 22 samples. Twelve U-series ages (between 2.55 and 4.14 ka BP) were used to construct the age models, using ensembles of 2000 Monte Carlo simulations for each proxy using the MATLAB-based COPRA script (Breitenbach et al., 2012, https://doi.org/10.5194/cp-8-1765-2012).
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    Publication Date: 2024-01-19
    Description: This data set is part of a larger data harmonization effort to make lake sediment core data machine readable and comparable. Here we standardized grain size element data of sediment core EN18208, retrieved in 2018 from Lake Ilirney (Chukotka, Russia) at 10.76 m water depth. The glacial lake Ilirney is situated in the forest tundra mountain area and has one outflow, one main inflow and several smaller inflows. It lies at an elevation of ca. 428 m a.s.l. with a surface area of ca. 30 km2 and a maximum lake water depth of estimated 44 m. The 10.76 m sediment core was retrieved by a UWITEC piston corer during the RU-Land_2018_Chukotka expedition of the Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research (AWI, Germany, Potsdam) in cooperation with the North Eastern Federal State University (NEFU, Russia, Yakutsk). Grain-size was measured using a Malvern Mastersizer 3000 laser diffraction particle analyser.
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    Publication Date: 2024-01-19
    Description: This data set is part of a larger data harmonization effort to make lake sediment core data machine readable and comparable. Here we standardized mineral data of sediment core EN18208, retrieved in 2018 from Lake Ilirney (Chukotka, Russia) at 10.76 m water depth. The glacial lake Ilirney is situated in the forest tundra mountain area and has one outflow, one main inflow and several smaller inflows. It lies at an elevation of ca. 428 m a.s.l. with a surface area of ca. 30 km2 and a maximum lake water depth of estimated 44 m. The 10.76 m sediment core was retrieved by a UWITEC piston corer during the RU-Land_2018_Chukotka expedition of the Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research (AWI, Germany, Potsdam) in cooperation with the North Eastern Federal State University (NEFU, Russia, Yakutsk). Bulk mineralogy was analysed by (x-ray diffractometry (XRD) using a (PHILIPS, Netherlands) PW1820 goniometer.
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    Publication Date: 2024-01-19
    Description: This data set is part of a larger data harmonization effort to make lake sediment core data machine readable and comparable. Here we standardized radiocarbon and OSL age data of sediment core EN18208, retrieved in 2018 from Lake Ilirney (Chukotka, Russia) at 10.76 m water depth. The glacial lake Ilirney is situated in the forest tundra mountain area and has one outflow, one main inflow and several smaller inflows. It lies at an elevation of ca. 428 m a.s.l. with a surface area of ca. 30 km2 and a maximum lake water depth of estimated 44 m. The 10.76 m sediment core was retrieved by a UWITEC piston corer during the RU-Land_2018_Chukotka expedition of the Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research (AWI, Germany, Potsdam) in cooperation with the North Eastern Federal State University (NEFU, Russia, Yakutsk). Water content and organic matter was analysed at AWI Potsdam. Dried and milled samples were analysed using a Vario EL III carbon-nitrogen-sulphur analyser. Organic carbon content was determined using a Vario MAX C analyser.
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 11
    Publication Date: 2023-09-18
    Description: Surface air temperature measurements obtained from different sensors are used to construct a unique time series with one minute time-interval. Apart from differences in design and environmental exposition, periods of missing data also exist in the data series of each sensor. A primary data set was selected in terms of quality and temporal extension. A combination of two different techniques is applied to complete this data set: one is based on the autocorrelation of the series and the other on measurements taken from other sensors. The resulting values constitute a complete series of surface air temperature at AGGO.
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 12
    Publication Date: 2024-01-24
    Description: This dataset contain stable isotope values for water samples collected ~weekly from the Rio Bermejo at the Lavalle bridge (-25.6513, -60.1277) from March 2016 to February 2018. Water samples were filtered to 0.2 micron using a custom filtration device. We measured d2H and d18O on a Picarro L-2140i Cavity Ring-Down Spectrometer at the GFZ Potsdam. Measurements were made in duplicate, normalized to the Vienna Standard Mean Ocean Water (VSMOW), and analytical uncertainty is reported as one standard deviation from the mean. River discharge was measured at the El Colorado gauging station, which is ~100 km down slope from the sampling location.
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 13
    Publication Date: 2024-01-24
    Description: This dataset provides the geochemistry data for the Holocene sediment sequence retrieved from Lake Uddelermeer (The Netherlands) in 2012. Additionally, alkane concentrations for a set of modern leaf samples are provided. Concentrations of fossil alkanes, GDGTs as well as elemental (C, N, S, H) and compound-specific delta Deuterium measurements are presented against both depth (cm) and age (cal yr. BP). A total of 59 samples were analysed. Modern leaf alkane concentrations are presented as concentrations, 10 samples were analysed. The geochemical data provides information about regional vegetation change as well as changes in effective precipitation. It was produced to inform on the age and duration of major environmental transitions during the middle and late Holocene. Cores were retrieved from the lake using a 3-m long handheld piston corer deployed from a floating coring platform during field work in April and May 2012. Samples were obtained from splits of the core and processed in the laboratory of the University of Amsterdam (the Netherlands) using standard protocols (CNHS, alkane concentrations), the laboratory of Utrecht University (the Netherlands; GDGT concentrations) and at GFZ Potsdam (Germany; delta Deuterium). Name of the Campaign: UDD Event Label: UDD-E Method: Uwitec piston corer Latitude: 52.24652778 Longitude: 5.76097222 Elevation: 24m asl Date/Time of event: 2012-05-01T14:00:00 Further information about event: Lake sediment sequence retrieved using a 60 mm piston corer deployed from a floating platform.
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 14
    Publication Date: 2024-01-24
    Description: Water samples were filtered to 0.2 micron prior to measurement. Samples for cation analysis were acidified in the field to pH 〈 2 using 6N HNO3. Cation concentrations were measured with a Varian 720 inductively coupled plasma optical emission spectrometer (ICP-OES) at the GFZ Helmholtz Laboratory for the Geochemistry of the Earth Surface (HELGES), using SLRS-5 (Saint-Laurent River Surface, National Research Council - Conseil National de Recherches Canada) and USGS M212 and USGS T187 as external standards. We corrected for instrument drift by measuring an internal standard (GFZ-RW1) every 10 samples and we determined measurement uncertainty using calibration curve uncertainty. Anion concentrations were measured with a Dionex ICS1100 Ion Chromatograph, using USGS standards M206 and M212 as external standards for quality control, with uncertainty determined from triplicate analysis. We corrected cation concentrations for cyclic salt inputs following Bickle et al. (2005, doi:10.1016/j.gca.2004.11.019).
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 15
    Publication Date: 2023-01-30
    Description: Despite the importance of surface energy budgets (SEBs) for land-climate interactions in the Arctic, uncertainties in their prediction persist. In situ observational data of SEB components - useful for research and model validation - are collected at relatively few sites across the terrestrial Arctic, and not all available datasets are readily interoperable. Furthermore, the terrestrial Arctic consists of a diversity of vegetation types, which are generally not well represented in land surface schemes of current Earth system models. This dataset describes the data generated in a literature synthesis, covering 358 study sites on vegetation or glacier (〉=60°N latitude), which contained surface energy budget observations. The literature synthesis comprised 148 publications searched on the ISI Web of Science Core Collection.
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 16
    Publication Date: 2023-02-09
    Description: The rewetting of peatlands is a promising measure to mitigate greenhouse gas (GHG) emissions by preventing the further mineralization of the peat soil through aeration. In coastal peatland, the rewetting with brackish water can increase the GHG mitigation potential by the introduction of sulfate, a terminal electron acceptor (TEA). Sulfate is known to lower the CH4 production and thus, its emission by favoring the growth of sulfate-reducers, which outcompete methanogens for substrate. The data contain porewater variables such as pH, electrical conductivity (EC) and sulfate, chloride, dissolved CO2 and CH4 concentrations, as well as absolute abundances of methane- and sulfate-cycling microbial communities. The data were collected in spring and autumn 2019 after a storm surge with brackish water inflow in January 2019. Field sampling was conducted in the nature reserve Heiligensee and Hütelmoor in North-East Germany, close to the Southern Baltic Sea coast. We took peat cores using a Russian peat corer in addition to pore water diffusion samplers and plastic liners (length: 60cm; inner diameter 10 cm) at four locations along a transect from further inland towards the Baltic Sea. We wanted to compare the soil and pore water geochemistry as well as the microbial communities after the brackish water inflow to the common freshwater rewetting state. Pore water was extracted using pore water suction samplers in the lab and environmental variables were quantified with an ICP. Microbial samples were sampled from the peat core using sterile equipment. We used quantitative polymerase chain reaction (qPCR) to characterize pools of DNA and cDNA targeting total and putatively active bacteria and archaea. qPCR was performed on key functional genes of methane production (mcrA), aerobic methane oxidation (pmoA) and sulfate reduction (dsrB) in addition to the 16S rRNA gene for the absolute abundance of total prokaryotes. Furthermore, we retrieved soil plugs to determine the concentrations and isotopic signatures of dissolved trace gases (CO2/DIC and CH4) in the pore water.
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 17
    Publication Date: 2023-01-30
    Description: This dataset provides annually resolved microfacies data from ICDP core 5017-1-A, retrieved from the deep northern Dead Sea basin in 2010/11, for the last glacial-interglacial transition (ca. 14-13 ka BP). Sediments of the Lisan Formation were investigated between ~94.7 and 91.8 m sediment depth below lake floor (lithozone C2) by continuous thin section microscopy. Thin sections were prepared following the standard procedure by Brauer and Casanova (2001) that was adjusted for salty sediments. Thin section analyses were performed on overlapping large-scale thin sections using a Zeiss Axiolab pol microscope at magnifications of 50-400x. Microfacies analyses included varve counting and measurements of varve and sublayer thickness. The amount of varves in erosional gaps was interpolated and the position of mass flow deposits (MFD) is marked.
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 18
    Publication Date: 2023-01-30
    Description: We present sea ice temperature and salinity data from first-year ice (FYI) and second-year ice (SYI) relevant to the temporal development of sea ice permeability and brine drainage efficiency from the early growth phase in October 2019 to the onset of spring warming in May 2020. Our dataset was collected in the central Arctic Ocean during the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) Expedition in 2019 to 2020. MOSAiC was an international transpolar drift expedition in which the German icebreaker RV Polarstern anchored into an ice floe to gain new insights into Arctic climate over a full annual cycle. In October 2019, RV Polarstern moored to an ice floe in the Siberian sector of the Arctic at 85 degrees north and 137 degrees east to begin the drift towards the North Pole and the Fram Strait via the Transpolar Drift Stream. The data presented here were collected during the first three legs of the expedition, so all the coring activities took place on the same floe. The end dates of legs 1, 2, and 3 were 13 December, 24 February, and 4 June, respectively. The dataset contributed to a baseline study entitled, Deciphering the properties of different Arctic ice types during the growth phase of the MOSAiC floes: Implications for future studies. The study highlights downward directed gas pathways in FYI and SYI by inferring sea ice permeability and potential brine release from several time series of temperature and salinity measurements. The physical properties presented in this paper lay the foundation for subsequent analyses on actual gas contents measured in the ice cores, as well as air-ice and ice-ocean gas fluxes. Sea ice cores were collected with a Kovacs Mark II 9 cm diameter corer. To measure ice temperatures, about 4.5 cm deep holes were drilled into the core (intervals varied by site and leg) . The temperatures were measured by a digital thermometer within minutes after the cores were retrieved. The ice cores were placed into pre-labelled plastic sleeves sealed at the bottom end. The ice cores were transported to RV Polarstern and stored in a -20 degrees Celsius freezer. Each of the cores was sub-sampled, melted at room temperature, and processed for salinity within one or two days. The practical salinity was estimated by measuring the electrical conductivity and temperature of the melted samples using a WTW Cond 3151 salinometer equipped with a Tetra-Con 325 four-electrode conductivity cell. The practical salinity represents the the salinity estimated from the electrical conductivity of the solution. The dataset also contains derived variables, including sea ice density, brine volume fraction, and the Rayleigh number.
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 19
    Publication Date: 2023-01-30
    Description: 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.
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 20
    Publication Date: 2023-01-30
    Description: We present sea ice temperature and salinity data from first-year ice (FYI) and second-year ice (SYI) relevant to the temporal development of sea ice permeability and brine drainage efficiency from the early growth phase in October 2019 to the onset of spring warming in May 2020. Our dataset was collected in the central Arctic Ocean during the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) Expedition in 2019 to 2020. MOSAiC was an international transpolar drift expedition in which the German icebreaker RV Polarstern anchored into an ice floe to gain new insights into Arctic climate over a full annual cycle. In October 2019, RV Polarstern moored to an ice floe in the Siberian sector of the Arctic at 85 degrees north and 137 degrees east to begin the drift towards the North Pole and the Fram Strait via the Transpolar Drift Stream. The data presented here were collected during the first three legs of the expedition, so all the coring activities took place on the same floe. The end dates of legs 1, 2, and 3 were 13 December, 24 February, and 4 June, respectively. The dataset contributed to a baseline study entitled, Deciphering the properties of different Arctic ice types during the growth phase of the MOSAiC floes: Implications for future studies. The study highlights downward directed gas pathways in FYI and SYI by inferring sea ice permeability and potential brine release from several time series of temperature and salinity measurements. The physical properties presented in this paper lay the foundation for subsequent analyses on actual gas contents measured in the ice cores, as well as air-ice and ice-ocean gas fluxes. Sea ice cores were collected with a Kovacs Mark II 9 cm diameter corer. To measure ice temperatures, about 4.5 cm deep holes were drilled into the core (intervals varied by site and leg) . The temperatures were measured by a digital thermometer within minutes after the cores were retrieved. The ice cores were placed into pre-labelled plastic sleeves sealed at the bottom end. The ice cores were transported to RV Polarstern and stored in a -20 degrees Celsius freezer. Each of the cores was sub-sampled, melted at room temperature, and processed for salinity within one or two days. The practical salinity was estimated by measuring the electrical conductivity and temperature of the melted samples using a WTW Cond 3151 salinometer equipped with a Tetra-Con 325 four-electrode conductivity cell. The practical salinity represents the the salinity estimated from the electrical conductivity of the solution. The dataset also contains derived variables, including sea ice density, brine volume fraction, and the Rayleigh number.
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 21
    Publication Date: 2023-01-30
    Description: These datasets describe sediment samples taken from the Batagay megaslump, located in Yana Uplands in northeastern Siberia. Most sediment samples were taken from the slump headwall (B19-P1) by rapelling down on a rope from the slump surface and taking samples with a hole saw (diameter 55 mm, 40 mm deep) mounted on a handheld power drill. A second profile (B19-02) of the lowest part of the slump headwall was sampled (~100 m south) using a hammer and axe from the slump floor. Two permafrost sediment blocks (B19-03 and B19-04) at the slump bottom that had fallen from the headwall were sampled using a chainsaw. Finally, a baidzherakh (thermokarst mound; B19-05) in the north of the slump was sampled using a hammer and axe. The samples cover 5 stratigraphical units: 1. lower ice complex, 2. lower sand unit, 3. woody layer, 4. upper ice complex, 5. Holocene cover.
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 22
    Publication Date: 2023-01-30
    Description: 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.
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 23
    Publication Date: 2023-01-30
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 24
    Publication Date: 2023-01-30
    Description: We present sea ice temperature and salinity data from first-year ice (FYI) and second-year ice (SYI) relevant to the temporal development of sea ice permeability and brine drainage efficiency from the early growth phase in October 2019 to the onset of spring warming in May 2020. Our dataset was collected in the central Arctic Ocean during the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) Expedition in 2019 to 2020. MOSAiC was an international transpolar drift expedition in which the German icebreaker RV Polarstern anchored into an ice floe to gain new insights into Arctic climate over a full annual cycle. In October 2019, RV Polarstern moored to an ice floe in the Siberian sector of the Arctic at 85 degrees north and 137 degrees east to begin the drift towards the North Pole and the Fram Strait via the Transpolar Drift Stream. The data presented here were collected during the first three legs of the expedition, so all the coring activities took place on the same floe. The end dates of legs 1, 2, and 3 were 13 December, 24 February, and 4 June, respectively. The dataset contributed to a baseline study entitled, Deciphering the properties of different Arctic ice types during the growth phase of the MOSAiC floes: Implications for future studies. The study highlights downward directed gas pathways in FYI and SYI by inferring sea ice permeability and potential brine release from several time series of temperature and salinity measurements. The physical properties presented in this paper lay the foundation for subsequent analyses on actual gas contents measured in the ice cores, as well as air-ice and ice-ocean gas fluxes. Sea ice cores were collected with a Kovacs Mark II 9 cm diameter corer. To measure ice temperatures, about 4.5 cm deep holes were drilled into the core (intervals varied by site and leg) . The temperatures were measured by a digital thermometer within minutes after the cores were retrieved. The ice cores were placed into pre-labelled plastic sleeves sealed at the bottom end. The ice cores were transported to RV Polarstern and stored in a -20 degrees Celsius freezer. Each of the cores was sub-sampled, melted at room temperature, and processed for salinity within one or two days. The practical salinity was estimated by measuring the electrical conductivity and temperature of the melted samples using a WTW Cond 3151 salinometer equipped with a Tetra-Con 325 four-electrode conductivity cell. The practical salinity represents the the salinity estimated from the electrical conductivity of the solution. The dataset also contains derived variables, including sea ice density, brine volume fraction, and the Rayleigh number.
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 25
    Publication Date: 2023-01-30
    Description: Rock magnetic and paleomagnetic results covering the past 30 ka were constructed from two sediment cores MSM33_856-1 (MSM33-55-1) and MSM33_855-1 (54-3) from the Black Sea. After the Mediterranean Sea water ingression, finely laminated organic-rich sapropelic sediments and coccolith oozes were deposited in the Black Sea since about 8.3 ka. Relict magnetic minerals in the Black Sea sarpoples are ferrous hemoilmenite, Fe-Mn and Fe-Cr spinels, and magnetite inclusions. In sediments deposited between about 14 and 8 ka, greigite and pyrite were formed in sediments because of the seawater penetration from overlying sediments after the seawater ingression. Before ~14 ka, the Black Sea sediments are dominated by detrital (titano-)magnetite minerals and the sporadically formed greigite which has SIRM/kLF ratios 〉 10 kAm-2. By comparison with detrital (titano-)magnetite samples between 20-30 ka, we found that relict magnetic mineral samples between 0-8.3 ka have similar behavior in recording the geomagnetic field. Moreover, the geomagnetic field variations reconstructed from the Black Sea sapropels are comparable with other validated regional datasets for the past 8.3 ka. The natural remanent magnetization (NRM) and the anhysteretic remanent magnetization (ARM) were measured with a 2G Enterprises 755 SRM (cryogenic) long-core magnetometer equipped with a sample holder for eight discrete samples at a separation of 20 cm. The magnetometer's in-line tri-axial alternating field (AF) demagnetizer was used to demagnetize the NRM and ARM of the samples. The NRM was measured after application of AF peak amplitudes of 0, 5, 10, 15, 20, 30, 40, 50, 65, 80, and 100 mT. Directions of the characteristic remanent magnetization (ChRM) were determined by principle component analysis (PCA) according to Kirschvink (1980). The error range of the ChRM is given as the maximum angular deviation (MAD). The ARM was imparted along the samples' z-axis with a static field of 0.05 mT and an AF field of 100 mT. Demagnetization then was performed in steps of 0, 10, 20, 30, 40, 50, 65, and 80 mT. The median destructive field of the ARM (MDFARM) was determined to estimate the coercivity of the sediments. The slope of NRM versus ARM of common demagnetization steps was used to determine the relative paleointensity (RPI). In most cases, demagnetization steps from 20 to 65 mT were used to determine the RPI.
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 26
    Publication Date: 2023-01-30
    Description: This dataset provides data for four third-degree tidal constituents used in the publication of Sulzbach et al (2022). The tidal constituents provided are the 3M1, 3M3, 3N2 and 3L2 for 134 globally distributed stations. The tide information, such as the nodal modulations of these tides, are taken from Table 1 and Table S2 of Ray (2020). These tidal constants are estimated using the GESLA dataset (Woodworth et al 2014) following the approach presented in Piccioni et al (2019). This record is an add-on to the full TICON dataset (https://doi.org/10.1594/PANGAEA.896587), using exactly the same data format and pre-processing. These steps include using tide gauge data that contains at least ten years of continuous data. Further, the dataset is restricted to only contain open ocean tide gauges by limiting it to a mean surrounding depth of tide gauges to be deeper than 500 meters in a 2-degree radius and excluding stations not native to the ocean domain of the employed tidal model TiME. Duplicate and closely neighbouring tide gauges, found within a 0.2-degree radius, are also removed from the dataset. This resulted in the availability of the four tidal constants for 134 tide gauges. The results are stored in one tab-separated text/ASCII file with 13 columns: 1. Latitude of the tide gauge station 2. Longitude of the tide gauge station 3. Constituent name 4. Amplitude (in cm) 5. Phase (in degrees) 6. Standard deviation of the amplitude (in cm) 7. Standard deviation of the phase (in degrees) 8. Percentage of missing observations 9. Total number of observations analyzed 10. Length of the maximum temporal gap found in the time series in days 11. Date of the first observation 12. Date of the last observation 13. Code that corresponds to the original source of the record TICON is a useful and easy-to-handle data set for tide model validation and allows the users to select the records according to the different criteria most suitable for their purposes. The options span from the choice of a geographical region to the use of single constituents or time periods.
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 27
    Publication Date: 2023-01-30
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 28
    Publication Date: 2023-01-30
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 29
    Publication Date: 2023-01-30
    Description: These datasets provide sedimentological data partly at annual resolution and an age model for the lateglacial part of (1) the ICDP sediment core 5017-1-A retrieved from the deep northern Dead Sea basin in 2010/11, and (2) for the Masada outcrop located at the southwestern shore of the Dead Sea sampled in 2018. The here investigated two sediment sections cover the last glacial-interglacial transition (ca. 17-11.5 ka BP) in the hydroclimatically sensitive Levant, when the water level of Lake Lisan – the precursor of the Dead Sea – dropped dramatically from its glacial high-stand to the Holocene low levels. Here, we analyze the interval between the last two gypsum units – the Upper Gypsum Unit (UGU) and the Additional Gypsum Unit (AGU) – which were also used to correlate the two sites. In the ICDP core this section is located between ~101 and 88.5 m sediment depth below lake floor and at Masada it encompasses the uppermost ~3.8 m sediments of the Lisan Formation, which form the terminal deposit at this site. Due to the lake level decline, the complete transition into the Holocene is only recorded in the ICDP core, while sedimentation at Masada terminates earlier. The microfacies was investigated by continuous thin section microscopy, while additional macroscopic information is provided from over- and underlying sediment sections. A revised chronology using age modelling in OxCal (Ramsey 2008; Ramsey 2009; Ramsey and Lee 2013) was developed for the ICDP core and a floating varve chronology was constructed at Masada. Using these new microfacies data from marginal (Masada) and deep-water (ICDP core) sediments, the hydroclimatic variability during the final stage of Lake Lisan can be reconstructed, which could provide important insights into the development of human sedentism in the region at this time.
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 30
    Publication Date: 2023-01-30
    Description: We present sea ice temperature and salinity data from first-year ice (FYI) and second-year ice (SYI) relevant to the temporal development of sea ice permeability and brine drainage efficiency from the early growth phase in October 2019 to the onset of spring warming in May 2020. Our dataset was collected in the central Arctic Ocean during the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) Expedition in 2019 to 2020. MOSAiC was an international transpolar drift expedition in which the German icebreaker RV Polarstern anchored into an ice floe to gain new insights into Arctic climate over a full annual cycle. In October 2019, RV Polarstern moored to an ice floe in the Siberian sector of the Arctic at 85 degrees north and 137 degrees east to begin the drift towards the North Pole and the Fram Strait via the Transpolar Drift Stream. The data presented here were collected during the first three legs of the expedition, so all the coring activities took place on the same floe. The end dates of legs 1, 2, and 3 were 13 December, 24 February, and 4 June, respectively. The dataset contributed to a baseline study entitled, Deciphering the properties of different Arctic ice types during the growth phase of the MOSAiC floes: Implications for future studies. The study highlights downward directed gas pathways in FYI and SYI by inferring sea ice permeability and potential brine release from several time series of temperature and salinity measurements. The physical properties presented in this paper lay the foundation for subsequent analyses on actual gas contents measured in the ice cores, as well as air-ice and ice-ocean gas fluxes. Sea ice cores were collected with a Kovacs Mark II 9 cm diameter corer. To measure ice temperatures, about 4.5 cm deep holes were drilled into the core (intervals varied by site and leg) . The temperatures were measured by a digital thermometer within minutes after the cores were retrieved. The ice cores were placed into pre-labelled plastic sleeves sealed at the bottom end. The ice cores were transported to RV Polarstern and stored in a -20 degrees Celsius freezer. Each of the cores was sub-sampled, melted at room temperature, and processed for salinity within one or two days. The practical salinity was estimated by measuring the electrical conductivity and temperature of the melted samples using a WTW Cond 3151 salinometer equipped with a Tetra-Con 325 four-electrode conductivity cell. The practical salinity represents the the salinity estimated from the electrical conductivity of the solution. The dataset also contains derived variables, including sea ice density, brine volume fraction, and the Rayleigh number.
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 31
    Publication Date: 2023-01-30
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 32
    Publication Date: 2023-01-30
    Description: This dataset provides annually resolved microfacies data from ICDP core 5017-1-A, retrieved from the deep northern Dead Sea basin in 2010/11, for the last glacial-interglacial transition (ca. 17-11.5 ka BP). Sediments of the Lisan Formation were investigated between ~101 and 88.5 m sediment depth below lake floor by continuous thin section microscopy, while additional macroscopic information is provided from core catchers, as well as from over- and underlying sediment sections. Thin sections were prepared following the standard procedure by Brauer and Casanova (2001) that was adjusted for salty sediments. Thin section analyses were performed on overlapping large-scale thin sections using a Zeiss Axiolab pol microscope at magnifications of 50-400x. Microfacies analyses included varve counting and measurements of varve and sublayer thickness.
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 33
    Publication Date: 2023-01-30
    Description: Despite the importance of surface energy budgets (SEBs) for land-climate interactions in the Arctic, uncertainties in their prediction persist. In situ observational data of SEB components - useful for research and model validation - are collected at relatively few sites across the terrestrial Arctic, and not all available datasets are readily interoperable. Furthermore, the terrestrial Arctic consists of a diversity of vegetation types, which are generally not well represented in land surface schemes of current Earth system models. This dataset contains metadata information about surface energy budget components measured at 64 tundra and glacier sites 〉60° N across the Arctic. This information was taken from the open-access repositories FLUXNET, Ameriflux, AON, GC-Net and PROMICE. The contained datasets are associated with the publication vegetation type as an important predictor of the Arctic Summer Land Surface Energy Budget by Oehri et al. 2022, and intended to support research of surface energy budgets and their relationship with environmental conditions, in particular vegetation characteristics across the terrestrial Arctic.
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 34
    Publication Date: 2023-01-30
    Description: This dataset provides the results from Bayesian age depth modelling in OxCal for ICDP core 5017-1-A, retrieved from the deep northern Dead Sea basin in 2010/11, for the last glacial-interglacial transition between ~101 and 88.5 m sediment depth below lake floor (ca. 17-11.5 ka BP). The model was performed in OxCal v.4.4 using a P_Sequence (1,1,C(-2,2)) (Ramsey 2008; Ramsey 2009; Ramsey and Lee 2013) and includes three tephrochronological ages from Neugebauer et al. (2021) and three radiocarbon ages from Kitagawa et al. (2017).
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 35
    Publication Date: 2023-01-30
    Description: Despite the importance of surface energy budgets (SEBs) for land-climate interactions in the Arctic, uncertainties in their prediction persist. In situ observational data of SEB components - useful for research and model validation - are collected at relatively few sites across the terrestrial Arctic, and not all available datasets are readily interoperable. Furthermore, the terrestrial Arctic consists of a diversity of vegetation types, which are generally not well represented in land surface schemes of current Earth system models. This dataset comprises harmonized, standardized and aggregated in-situ observations of surface energy budget components measured at 64 sites on vegetated and glaciated sites north of 60° latitude, in the time period from 1994 till 2021. The surface energy budget components include net radiation, sensible heat flux, latent heat flux, ground heat flux, net shortwave radiation, net longwave radiation, surface temperature and albedo, which were aggregated to daily mean, minimum and maximum values from hourly and half-hourly measurements. Data were retrieved from the monitoring networks FLUXNET, AmeriFlux, AON, GC-Net and PROMICE.
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 36
    Publication Date: 2023-01-30
    Description: We present sea ice temperature and salinity data from first-year ice (FYI) and second-year ice (SYI) relevant to the temporal development of sea ice permeability and brine drainage efficiency from the early growth phase in October 2019 to the onset of spring warming in May 2020. Our dataset was collected in the central Arctic Ocean during the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) Expedition in 2019 to 2020. MOSAiC was an international transpolar drift expedition in which the German icebreaker RV Polarstern anchored into an ice floe to gain new insights into Arctic climate over a full annual cycle. In October 2019, RV Polarstern moored to an ice floe in the Siberian sector of the Arctic at 85 degrees north and 137 degrees east to begin the drift towards the North Pole and the Fram Strait via the Transpolar Drift Stream. The data presented here were collected during the first three legs of the expedition, so all the coring activities took place on the same floe. The end dates of legs 1, 2, and 3 were 13 December, 24 February, and 4 June, respectively. The dataset contributed to a baseline study entitled, Deciphering the properties of different Arctic ice types during the growth phase of the MOSAiC floes: Implications for future studies. The study highlights downward directed gas pathways in FYI and SYI by inferring sea ice permeability and potential brine release from several time series of temperature and salinity measurements. The physical properties presented in this paper lay the foundation for subsequent analyses on actual gas contents measured in the ice cores, as well as air-ice and ice-ocean gas fluxes. Sea ice cores were collected with a Kovacs Mark II 9 cm diameter corer. To measure ice temperatures, about 4.5 cm deep holes were drilled into the core (intervals varied by site and leg) . The temperatures were measured by a digital thermometer within minutes after the cores were retrieved. The ice cores were placed into pre-labelled plastic sleeves sealed at the bottom end. The ice cores were transported to RV Polarstern and stored in a -20 degrees Celsius freezer. Each of the cores was sub-sampled, melted at room temperature, and processed for salinity within one or two days. The practical salinity was estimated by measuring the electrical conductivity and temperature of the melted samples using a WTW Cond 3151 salinometer equipped with a Tetra-Con 325 four-electrode conductivity cell. The practical salinity represents the the salinity estimated from the electrical conductivity of the solution. The dataset also contains derived variables, including sea ice density, brine volume fraction, and the Rayleigh number.
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 37
    Publication Date: 2023-01-30
    Description: We present sea ice temperature and salinity data from first-year ice (FYI) and second-year ice (SYI) relevant to the temporal development of sea ice permeability and brine drainage efficiency from the early growth phase in October 2019 to the onset of spring warming in May 2020. Our dataset was collected in the central Arctic Ocean during the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) Expedition in 2019 to 2020. MOSAiC was an international transpolar drift expedition in which the German icebreaker RV Polarstern anchored into an ice floe to gain new insights into Arctic climate over a full annual cycle. In October 2019, RV Polarstern moored to an ice floe in the Siberian sector of the Arctic at 85 degrees north and 137 degrees east to begin the drift towards the North Pole and the Fram Strait via the Transpolar Drift Stream. The data presented here were collected during the first three legs of the expedition, so all the coring activities took place on the same floe. The end dates of legs 1, 2, and 3 were 13 December, 24 February, and 4 June, respectively. The dataset contributed to a baseline study entitled, Deciphering the properties of different Arctic ice types during the growth phase of the MOSAiC floes: Implications for future studies. The study highlights downward directed gas pathways in FYI and SYI by inferring sea ice permeability and potential brine release from several time series of temperature and salinity measurements. The physical properties presented in this paper lay the foundation for subsequent analyses on actual gas contents measured in the ice cores, as well as air-ice and ice-ocean gas fluxes. Sea ice cores were collected with a Kovacs Mark II 9 cm diameter corer. To measure ice temperatures, about 4.5 cm deep holes were drilled into the core (intervals varied by site and leg) . The temperatures were measured by a digital thermometer within minutes after the cores were retrieved. The ice cores were placed into pre-labelled plastic sleeves sealed at the bottom end. The ice cores were transported to RV Polarstern and stored in a -20 degrees Celsius freezer. Each of the cores was sub-sampled, melted at room temperature, and processed for salinity within one or two days. The practical salinity was estimated by measuring the electrical conductivity and temperature of the melted samples using a WTW Cond 3151 salinometer equipped with a Tetra-Con 325 four-electrode conductivity cell. The practical salinity represents the the salinity estimated from the electrical conductivity of the solution. The dataset also contains derived variables, including sea ice density, brine volume fraction, and the Rayleigh number.
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 38
    Publication Date: 2023-01-30
    Description: This dataset describes two 17 m long sediment cores taken from beneath two thermokarst lakes in the Yukechi Alas, Central Yakutia, Russia. The first core was taken from below an Alas thermokarst lake (YU-L7; 61.76397°N, 130.46442°E) and the second core below and Yedoma lake (YU-L15; 61.76086°N, 130.47466°E). The dataset presents biogeochemical and biomarker parameters of sediment cores YU-L7 and YU-L15. Biogeochemical analyses include total carbon (TC) content, total organic carbon (TOC) content, total nitrogen (TN) content. Biomarker parameters include the n-alkane concentration, average chain length (ACL), carbon preference index (CPI), brGDGT concentration, archaeol concentration and the isoGDGT-0 concentration. The n-alkanes were measured in the aliphatic fraction by gas chromatography-mass spectromety using a Trace GC Ultra coupled to a DSQ MS. The branched and isoprenoid glycerol dialkyl glycerol tetraethers, as well as the dialkyl glycerol diether lipid (archaeol) were measured in the NSO fraction using a Shimadzu LC-10AD high-performance liquid chromatograph coupled to a Finnigan TSQ 7000 mass spectrometer via an atmospheric pressure chemical ionization interface. The pH soil is the sediment pH which was assessed by adding 6.12 mL of 0.01 M CaCl~2~ to ~2.5 g dried sediment and measuring with a Multilab 540 (WTW) at 20°C.
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 39
    Publication Date: 2023-01-30
    Description: We present sea ice temperature and salinity data from first-year ice (FYI) and second-year ice (SYI) relevant to the temporal development of sea ice permeability and brine drainage efficiency from the early growth phase in October 2019 to the onset of spring warming in May 2020. Our dataset was collected in the central Arctic Ocean during the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) Expedition in 2019 to 2020. MOSAiC was an international transpolar drift expedition in which the German icebreaker RV Polarstern anchored into an ice floe to gain new insights into Arctic climate over a full annual cycle. In October 2019, RV Polarstern moored to an ice floe in the Siberian sector of the Arctic at 85 degrees north and 137 degrees east to begin the drift towards the North Pole and the Fram Strait via the Transpolar Drift Stream. The data presented here were collected during the first three legs of the expedition, so all the coring activities took place on the same floe. The end dates of legs 1, 2, and 3 were 13 December, 24 February, and 4 June, respectively. The dataset contributed to a baseline study entitled, Deciphering the properties of different Arctic ice types during the growth phase of the MOSAiC floes: Implications for future studies. The study highlights downward directed gas pathways in FYI and SYI by inferring sea ice permeability and potential brine release from several time series of temperature and salinity measurements. The physical properties presented in this paper lay the foundation for subsequent analyses on actual gas contents measured in the ice cores, as well as air-ice and ice-ocean gas fluxes. Sea ice cores were collected with a Kovacs Mark II 9 cm diameter corer. To measure ice temperatures, about 4.5 cm deep holes were drilled into the core (intervals varied by site and leg) . The temperatures were measured by a digital thermometer within minutes after the cores were retrieved. The ice cores were placed into pre-labelled plastic sleeves sealed at the bottom end. The ice cores were transported to RV Polarstern and stored in a -20 degrees Celsius freezer. Each of the cores was sub-sampled, melted at room temperature, and processed for salinity within one or two days. The practical salinity was estimated by measuring the electrical conductivity and temperature of the melted samples using a WTW Cond 3151 salinometer equipped with a Tetra-Con 325 four-electrode conductivity cell. The practical salinity represents the the salinity estimated from the electrical conductivity of the solution. The dataset also contains derived variables, including sea ice density, brine volume fraction, and the Rayleigh number.
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 40
    Publication Date: 2023-01-30
    Description: Despite the importance of surface energy budgets (SEBs) for land-climate interactions in the Arctic, uncertainties in their prediction persist. In-situ observational data of SEB components - useful for research and model validation - are collected at relatively few sites across the terrestrial Arctic, and not all available datasets are readily interoperable. Furthermore, the terrestrial Arctic consists of a diversity of vegetation types, which are generally not well represented in land surface schemes of current Earth system models. Therefore, we here provide four datasets comprising: 1. Harmonized, standardized and aggregated in situ observations of SEB components at 64 vegetated and glaciated sites north of 60° latitude, in the time period 1994-2021 2. A description of all study sites and associated environmental conditions, including the vegetation types, which correspond to the classification of the Circumpolar Arctic Vegetation Map (CAVM, Raynolds et al. 2019). 3. Data generated in a literature synthesis from 358 study sites on vegetation or glacier (〉=60°N latitude) covered by 148 publications. 4. Metadata, including data contributor information and measurement heights of variables associated with Oehri et al. 2022.
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 41
    Publication Date: 2023-01-30
    Description: This dataset provides lithological data from ICDP core 5017-1-A, retrieved from the deep northern Dead Sea basin in 2010/11, for the last glacial-interglacial transition (ca. 17-11.5 ka BP). The microfacies of the Lisan Formation was investigated between ~101 and 88.5 m sediment depth below lake floor by continuous thin section microscopy, while additional macroscopic information is provided from core catchers, as well as from over- and underlying sediment sections. Thin sections were prepared following the standard procedure by Brauer and Casanova (2001) that was adjusted for salty sediments. Thin section analyses were performed on overlapping large-scale thin sections using a Zeiss Axiolab pol microscope at magnifications of 50-400x.
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 42
    Publication Date: 2023-01-30
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 43
    Publication Date: 2023-01-30
    Description: This dataset contains observations of water discharge rates and concentrations of dissolved organic carbon (DOC) and dissolved inorganic carbon (DIC) from a polygonal tundra site in the Lena River Delta, Russia. This dataset also contains lateral carbon fluxes of DOC and DIC that were estimated from these observations. Additionally, this dataset contains vertical fluxes of carbon dioxide and methane from the same study site. All observations were recorded on Samoylov Island (N 72.377188, E 126.495144) in the summer of 2014. The abbreviations A1, A2 and B refer to three outflows on the island where the hydrological parameters were observed (A1: N 72.379991, E 126.480886; A2: N 72.380134, E 126.481433; B: N 72.381348, E 126.483482). All outflows were approximately 10 meters. More information can be found in https://doi.org/10.5194/bg-19-3863-2022.
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 44
    Publication Date: 2023-01-30
    Description: Despite the importance of surface energy budgets (SEBs) for land-climate interactions in the Arctic, uncertainties in their prediction persist. In situ observational data of SEB components - useful for research and model validation - are collected at relatively few sites across the terrestrial Arctic, and not all available datasets are readily interoperable. Furthermore, the terrestrial Arctic consists of a diversity of vegetation types, which are generally not well represented in land surface schemes of current Earth system models. This dataset describes the environmental conditions for 64 tundra and glacier sites (〉=60°N latitude) across the Arctic, for which in situ measurements of surface energy budget components were harmonized (see Oehri et al. 2022). These environmental conditions are (proxies of) potential drivers of SEB-components and could therefore be called SEB-drivers. The associated environmental conditions, include the vegetation types graminoid tundra, prostrate dwarf-shrub tundra, erect-shrub tundra, wetland complexes, barren complexes (≤ 40% horizontal plant cover), boreal peat bogs and glacier. These land surface types (apart from boreal peat bogs) correspond to the main classification units of the Circumpolar Arctic Vegetation Map (CAVM, Raynolds et al. 2019). For each site, additional climatic and biophysical variables are available, including cloud cover, snow cover duration, permafrost characteristics, climatic conditions and topographic conditions.
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 45
    Publication Date: 2023-02-01
    Description: This dataset contains over 30 marine Electrical Resistivity Tomography (ERT) profiles taken in September 2021 around Tuktoyaktuk Island (NWT / Beaufort Sea, Canada). The measurements were part of the “Mackenzie Delta Permafrost Field Campaign” (mCan2021) within the “Modular Observation solutions for Earth Systems” (MOSES) program. The collected profiles consist of numerous adjacent vertical soundings in a (quasi-symmetric) reciprocal Wenner-Schlumberger array, using a floating cable towed behind a boat. GPS records along the electrode streamer were taken, enabling the improvement of pre- processing by excluding measurements for which the cable was curved and electrode positions deviated too widely. The aim of the study was to determine the depth of the submarine permafrost. Cleaned data is provided in csv format.
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 46
    Publication Date: 2023-02-01
    Description: This collection contains permafrost related measurements in the Mackenzie Delta, NWT, Canada from the MOSES (Modular Observation Solutions for Earth Systems) field campaign in September 2021. The field campaign was focused on three subaquatic sites: a small thermokarst lake along the ITH just south of Trail Valley Creek, "Lake 3", an elongated lake with known methane occurence in the outer Mackenzie Delta, "Swiss Cheese Lake", and north and south of Tuktoyaktuk Island. At "Swiss Cheese Lake", we measured methane and CO2 concentrations in surface water and in the air above the lake, lake bed temperatures and detailed bathymetry. At "Lake 3" we measured active layer thickness on the lake banks, lake bed temperatures, and detailed bathymetry, as well as an ERT survey to estimate the talik depth below the lake. North and south of Tuktoyaktuk Island, we measured active layer thickness and sea bed temperatures and did an extensive ERT survey to obtain the depth of the subsea permafrost table. An additional passive seismic survey was carried out and the data is available at https://doi.org/10.5880/GIPP.202199.1.
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 47
    Publication Date: 2023-02-01
    Description: This dataset contains seven Electrical Resistivity Tomography (ERT) profiles taken in September 2021 at “Lake 3”, a thermokarst lake near the Inuvik-Tuktoyaktuk-Highway (ITH), about 50 km north of Inuvik (NWT, Canada). The measurements were part of the “Mackenzie Delta Permafrost Field Campaign” (mCan2021) within the “Modular Observation solutions for Earth Systems” (MOSES) program. The collected profiles consist of numerous adjacent vertical soundings in a (quasi-symmetric) reciprocal Wenner-Schlumberger array. In addition to surveys on the lake, using a floating cable towed behind a boat, two “amphibian” profiles were taken. Starting as purely terrestrial surveys using metal spike electrodes, the cable was then moved towards the lake with some of the electrodes floating on the water surface, and some still on land. The aim of the study was to determine permafrost properties on the land, to detect a possible talik beneath the lake and to especially be able to infer the transition between the two below the shoreline.
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 48
    facet.materialart.
    Unknown
    PANGAEA
    In:  EPIC3INTERACT Webinar on Data Repositories, Online, 2022-05-12Bremerhaven, PANGAEA
    Publication Date: 2022-10-04
    Repository Name: EPIC Alfred Wegener Institut
    Type: Conference , notRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 49
    Publication Date: 2023-01-27
    Description: 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.
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 50
    Publication Date: 2020-12-04
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 51
    Publication Date: 2020-12-04
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 52
    Publication Date: 2020-12-04
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 53
    Publication Date: 2020-12-04
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 54
    Publication Date: 2020-12-04
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 55
    Publication Date: 2020-12-04
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 56
    Publication Date: 2020-12-02
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 57
    Publication Date: 2020-12-02
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 58
    Publication Date: 2020-12-03
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 59
    Publication Date: 2020-12-03
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 60
    Publication Date: 2020-12-03
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 61
    Publication Date: 2020-11-24
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 62
    Publication Date: 2020-12-02
    Description: The sample set includes 25 newly sampled sea-level index points based on fossil microatoll measurements from 5 islands in the Spermonde Archipelago, 21 fossl microatoll samples previously published by Mann et al., 2016 from two Islands in the same study region and 20 marine and terrestrial limiting points (e.g. corals, shells and loamy clay) and one further sea-level index point from a Mangrove swamp published by De Klerk, 1982 and Tjia et al., 1972
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 63
    Publication Date: 2020-12-03
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 64
    Publication Date: 2020-12-03
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 65
    Publication Date: 2020-12-04
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 66
    Publication Date: 2020-12-04
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 67
    Publication Date: 2021-08-20
    Description: The main purpose of this project was to detect subsidence of the ground and of buildings in a permafrost affected landscape. Therefore, we surveyed many points using GNSS in the village of Ny Ålesund and in the watershed of the Bayelva River close to the long term observations.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Miscellaneous , notRev
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 68
    Publication Date: 2022-11-29
    Description: Pore water geochemistry and bulk sediment measurements of downcore profiles covering the upper 100 m-long sequence from site 1A, Lake Towuti, Indonesia
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 69
    facet.materialart.
    Unknown
    PANGAEA
    In:  EPIC3Bremerhaven, PANGAEA
    Publication Date: 2019-01-30
    Description: The purpose of this list of digital platforms is to facilitate the research of scientific data (articles, books, conferences, websites, indexers, etc.) by students of all undergraduate levels. The interface of platforms have similarities and because of this, low degree of difficulty of use. I emphasize that the key to an excellent literature search on digital platforms is to choose the right "keyword".
    Repository Name: EPIC Alfred Wegener Institut
    Type: PANGAEA Documentation , notRev
    Format: application/zip
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 70
    facet.materialart.
    Unknown
    PANGAEA
    In:  EPIC3Bremerhaven, PANGAEA
    Publication Date: 2019-03-21
    Repository Name: EPIC Alfred Wegener Institut
    Type: PANGAEA Documentation , notRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 71
    facet.materialart.
    Unknown
    PANGAEA
    In:  EPIC3Bremerhaven, PANGAEA
    Publication Date: 2019-03-21
    Repository Name: EPIC Alfred Wegener Institut
    Type: PANGAEA Documentation , notRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 72
    facet.materialart.
    Unknown
    PANGAEA
    In:  EPIC3Bremerhaven, PANGAEA
    Publication Date: 2019-03-21
    Repository Name: EPIC Alfred Wegener Institut
    Type: PANGAEA Documentation , notRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 73
    facet.materialart.
    Unknown
    PANGAEA
    In:  EPIC3Bremerhaven, PANGAEA
    Publication Date: 2019-03-21
    Repository Name: EPIC Alfred Wegener Institut
    Type: PANGAEA Documentation , notRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 74
    facet.materialart.
    Unknown
    PANGAEA
    In:  EPIC3Bremerhaven, PANGAEA
    Publication Date: 2019-01-22
    Repository Name: EPIC Alfred Wegener Institut
    Type: PANGAEA Documentation , notRev
    Format: application/pdf
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 75
    facet.materialart.
    Unknown
    PANGAEA
    In:  EPIC3Bremerhaven, PANGAEA
    Publication Date: 2019-03-21
    Repository Name: EPIC Alfred Wegener Institut
    Type: PANGAEA Documentation , notRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 76
    facet.materialart.
    Unknown
    PANGAEA
    In:  EPIC3Bremerhaven, PANGAEA
    Publication Date: 2020-03-30
    Repository Name: EPIC Alfred Wegener Institut
    Type: PANGAEA Documentation , notRev
    Format: application/zip
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 77
    facet.materialart.
    Unknown
    PANGAEA
    In:  EPIC3Bremerhaven, PANGAEA
    Publication Date: 2020-03-30
    Repository Name: EPIC Alfred Wegener Institut
    Type: PANGAEA Documentation , notRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 78
    facet.materialart.
    Unknown
    PANGAEA
    In:  EPIC3Bremerhaven, PANGAEA
    Publication Date: 2019-09-12
    Repository Name: EPIC Alfred Wegener Institut
    Type: PANGAEA Documentation , notRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 79
    facet.materialart.
    Unknown
    PANGAEA
    In:  EPIC3Bremerhaven, PANGAEA
    Publication Date: 2019-01-02
    Repository Name: EPIC Alfred Wegener Institut
    Type: PANGAEA Documentation , notRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 80
    facet.materialart.
    Unknown
    PANGAEA
    In:  EPIC3Bremerhaven, PANGAEA
    Publication Date: 2019-03-21
    Repository Name: EPIC Alfred Wegener Institut
    Type: PANGAEA Documentation , notRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 81
    facet.materialart.
    Unknown
    PANGAEA
    In:  EPIC3Bremerhaven, PANGAEA
    Publication Date: 2019-01-18
    Repository Name: EPIC Alfred Wegener Institut
    Type: PANGAEA Documentation , notRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 82
    facet.materialart.
    Unknown
    PANGAEA
    In:  EPIC3Bremerhaven, PANGAEA
    Publication Date: 2019-03-21
    Repository Name: EPIC Alfred Wegener Institut
    Type: PANGAEA Documentation , notRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 83
    facet.materialart.
    Unknown
    PANGAEA
    In:  EPIC3Bremerhaven, PANGAEA
    Publication Date: 2019-03-21
    Repository Name: EPIC Alfred Wegener Institut
    Type: PANGAEA Documentation , notRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 84
    facet.materialart.
    Unknown
    PANGAEA
    In:  EPIC3SponGES 2019 General Assembly Meeting, Wageningen, 2019-05-19-2019-05-24Bremerhaven, PANGAEA
    Publication Date: 2019-06-03
    Repository Name: EPIC Alfred Wegener Institut
    Type: Conference , notRev
    Format: application/zip
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 85
    facet.materialart.
    Unknown
    PANGAEA
    In:  EPIC3Coordination Workshop SPP 1158, 2019-09-25-2019-09-27Bremerhaven, PANGAEA
    Publication Date: 2019-09-30
    Repository Name: EPIC Alfred Wegener Institut
    Type: Conference , notRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 86
    Publication Date: 2020-03-30
    Repository Name: EPIC Alfred Wegener Institut
    Type: PANGAEA Documentation , notRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 87
    Publication Date: 2022-09-07
    Description: Here we provide two ArcGIS map packages with georeferenced files on the spatial distribution of sponges and echinoderms in the wider Weddell Sea (Antarctica), which were created in the context of the development of a marine protected area (MPA) in the Weddell Sea. Sponges: The map of interpolated occurrence of sponges is based on quantitative abundance data (Gerdes 2014 a - o) and on semi-quantitative data obtained by W. Arntz (retired; formerly AWI) (see Teschke & Brey 2019a for presence / absence records of the latter dataset). The abundance data were classified to be merged with the semi-quantitative data and an inverse distance weighted method was performed on the united dataset. Areas with very common occurrence of sponges occurred on the shelf near Brunt Ice Shelf along Riiser - Larsen Ice Shelf to Ekstrøm Ice Shelf. Echinoderms: A cluster analysis with species x station datasets of asteroids (Teschke & Brey 2019b), ophiuroids (Teschke & Brey 2019c) and holothurians (Gutt et al. 2014) from the Antarctic Weddell Sea indicated a particular cold-water echinoderm fauna on the Filchner shelf. We approximated this potential habitat by bottom temperature ≤ -1°, based on seawater temperature data from the Finite Element Sea Ice - Ocean Model provided by R. Timmermann (AWI). More information on the spatial analysis is given in working paper WG-EMM-16/03 submitted to the CCAMLR Working Group on Ecosystem Monitoring and Management (available at https://www.ccamlr.org/en/wg-emm-16).
    Repository Name: EPIC Alfred Wegener Institut
    Type: Other , NonPeerReviewed
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 88
    Publication Date: 2022-09-07
    Description: Here we provide four ArcGIS map packages with georeferenced files on the spatial distribution of demersal and pelagic fishes in the wider Weddell Sea (Antarctica), which were created in the context of the development of a marine protected area (MPA) in the Weddell Sea. Antarctic toothfish: The map of Dissostichus mawsoni occurrence probability is based on catch per unit effort (CPUE) data from the database of the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR) (data request: 03-08-2016) and on bathymetric data from the International Bathymetric Chart of the Southern Ocean (IBCSO). We fitted a four-parameter Weibull model to the simulated CPUE data per depth interval by means of the R package \textquotesinglefitdistrplus\textquotesingle. The highest D. mawsoni occurrence probability was shown at depths between 1500 and 2000 m and only approximately 20 % of the Antarctic toothfish population occurred deeper than 2000 m. Antarctic silverfish: The map of interpolated abundances of Pleuragramma antarctica was based on pelagic trawl survey data, which were collected during "Polarstern" cruises ANT-I/2, ANT-III/3 and in the context of the Lazarev Sea Krill Survey (LAKRIS) ("Polarstern" cruises ANT-XXI/4, ANT-XXIII/6, ANT-XXIV/2). The first mentioned data were provided by V. Siegel (retired; formerly Th\"unen Institute), the LAKRIS data by H. Flores (AWI). Those data were complemented by benthic trawl survey data, which were collected during seven "Polarstern" cruises between 1996 and 2011 (ANT-XIII/3, ANT-XV/3, ANT-XVII/3, ANT-XIX/5, ANT-XXI/2, ANT-XXIII/8, ANT-XXVII/3) and were provided by R. Knust (AWI) as well as by data on counts of fish species from trawl and dredge samples by Drescher et. (2012), Ekau et al. (2012a, b), Hureau et al. (2012), Kock et al. (2012) and W\"ohrmann et al. (2012). An inverse distance weighted interpolation was performed for a 10 nautical mile radius around each record. Areas with highest numbers of P. antarctica (〉 36 individuals/1000 m²) occurred offshore Riiser -Larsen Ice Shelf and on the southern Weddell Sea continental shelf offshore Filchner Ice Shelf. Demersal fish: The map of predicted habitat suitability for demersal fish is based on data, which were collected during seven "Polarstern" cruises between 1996 and 2011 (ANT-XIII/3, ANT-XV/3, ANT-XVII/3, ANT-XIX/5, ANT-XXI/2, ANT-XXIII/8, ANT-XXVII/3) and were provided by R. Knust (AWI). The habitat suitability model was developed by the use of the modelling package "biomod2". Most suitable habitat conditions for demersal fish in the wider Weddell Sea occurred on the continental shelf between approx. 5° and 30°W, on the shelf west and east of the tip of the Antarctic Peninsula as well as around the South Shetland and South Orkney Islands. Nesting sites of demersal fish: The map on observation of nesting sites of demersal fish is based on data, which were collected during "Polarstern" cruises ANT-XXVII/3, ANT-XXIX/9 and ANT-XXXI/2 and were obtained by T. Lund\"alv (retired; formerly University of Gothenburg), D. Gerdes (retired; formerly AWI) and E. Riginella (University of Padova), respectively. Those data were complemented by a literature research. Most nesting sites were observed west of 25°W, north of the tip of the Antarctic Peninsula and along the west coast of the Antarctic Peninsula. More information is given in the working paper WG-EMM-16/03 submitted to the CCAMLR Working Group on Ecosystem Monitoring and Management CCAMLR (available at https://www.ccamlr.org/en/wg-emm-16). Revised versions of the spatial analysis are described in working paper WG-SAM-17/30 and WS-SM-18/13 submitted to the CCAMLR Working Group on Statistics, Assessments and Modelling and the CCAMLR Workshop on Spatial Management, respectively (available at https://www.ccamlr.org/en/wg-sam-17; https://www.ccamlr.org/en/ws-sm-1
    Repository Name: EPIC Alfred Wegener Institut
    Type: Other , NonPeerReviewed
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 89
    Publication Date: 2022-09-07
    Description: Here, we provided four ArcGIS map packages with georeferenced files on the spatial distribution of Antarctic krill, Euphausia superba, (adults and larvae) and ice krill, Euphausia crystallorophias, in the wider Weddell Sea. The files were created in the context of the development of a marine protected area in the Weddell Sea. Antarctic krill (adults): The map of predicted habitat suitability for adult Antarctic krill was based on krill data from the database KRILLBASE (Atkinson et al., 2017; data request: 26-09-13). Those data were complemented by krill data, which were collected (a) during the Norwegian Antarctic research expedition 1976/77 (M/V "Polarsirkel"), (b) during two Soviet research cruises (RV "Gizhiga", 1977; RV "Volny Vetter", 1983), (c) in the context of the Lazarev Sea Krill Survey ("Polarstern" cruises ANT-XXI/4, ANT-XXIII/2, ANT-XXIII/6, ANT-XXIV/2) as well as (d) during "Polarstern" cruise ANT-XXIX/3. The habitat suitability model was developed by the use of the modelling package "biomod2". As predictor variables, we used (i) dissolved oxygen from the World Ocean Atlas 2013, (ii) ice coverage from AMSR-E sea ice maps, (iii) seawater temperature data from the Finite Element Sea Ice - Ocean Model (FESOM) provided by R. Timmermann (AWI), (iv) bathymetric data from the International Bathymetric Chart of the Southern Ocean (IBCSO) and (v) SeaWiFS chlorophyll-a concentration data. Most suitable habitat conditions for the Antarctic krill seem to occur near the tip of the Antarctic Peninsula, on the continental slope between 15°W and 15°E and on the Maud Rise plateau. Antarctic krill (larvae): The map of interpolated abundances of krill larvae is based on abundance data, which were collected (a) during the Norwegian Antarctic research expeditions 1976/77, 1977/78 and 1979/80 (M/V "Polarsirkel"), (b) in the context of the First International BIOMASS Experiment survey (FIBEX) (Walther Herwig cruise 1981) and the Lazarev Sea Krill Survey (LAKRIS) ("Polarstern" cruises ANT-XXI/4, ANT-XXIII/6) as well as (c) during "Polarstern" cruise ANT-VII/4 and the combined "Polarstern" (ANT-VIII/2) and R.V. "Akademik Fedorova" cruise. An inverse distance weighted (IDW) interpolation was performed for a 30 km radius around each krill larvae record. Areas with highest numbers of E. superba larvae (〉 1000 individuals/m²) occurred west of the Prime Meridian from approximately 65°S to the ice shelf. Ice krill (adults): The map of the potential habitat of E. crystallorophias was approximated by water depth from 0 m to 550 m, using bathymetric data from IBCSO, and mean sea surface temperature ≤ 0°C based on temperature data from FESOM provided by R. Timmermann (AWI). The map of interpolated density of individuals of E. crystallorophias is based on abundance data, which were collected (a) during the Norwegian Antarctic research expedition 1979/80 (M/V "Polarsirkel"), (b) during the German Antarctic research cruise 1975/76 with "Walther Herwig", (c) in the context of the Lazarev Sea Krill Survey ("Polarstern" cruises ANT-XXI/4, ANT-XXIII/2, ANT-XXIII/6, ANT-XXIV/2) as well as (d) during "Polarstern" cruise ANT-V/1-3, ANT-VII/4 and ANT-XXIX/3. An IDW interpolation was performed for a 30 km radius around each record of ice krill. Areas with highest densities of E. crystallorophias individuals occurred on the south-eastern Weddell Sea shelf and near the tip of the Antarctic Peninsula. Volker Siegel (retired; formerly Th\"unen Institute) provided the data for the Antarctic krill and ice krill. More information on the spatial analysis is given in working paper WG-EMM-16/03 submitted to the CCAMLR Working Group on Ecosystem Monitoring and Management (available at https://www.ccamlr.org/en/wg-emm-16)
    Repository Name: EPIC Alfred Wegener Institut
    Type: Other , NonPeerReviewed
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 90
    Publication Date: 2022-09-07
    Description: Here we provide four ArcGIS map packages with georeferenced files on the spatial distribution of Antarctic petrels, Ad\'elie penguins (breeders and non-breeders) and Emperor penguins in the wider Weddell Sea (Antarctica), which were created in the context of the development of a marine protected area in the Weddell Sea. Antarctic petrel (Thalassoica antarctica): We approximated potential foraging habitats of T. antarctica according to existing literature by ice coverage from AMSR-E sea ice maps, bathymetric data from the International Bathymetric Chart of the Southern Ocean (IBCSO), and seawater temperature data from the Finite Element Sea Ice - Ocean Model (FESOM) provided by R. Timmermann (AWI). Subsequently, we combined our Antarctic petrel model with the kernel utilization distribution model from Descamps et al. (2016). The authors kindly provided us with shape files showing the kernel utilization summer and winter distribution of Antarctic petrel breeding at Svarthamaren. Breeding locations and estimated number of breeding pairs were taken from van Franeker et al. (1999). Favourable habitat conditions for Antarctic petrels were predicted for the Lazarev Sea and along the eastern coast of the Weddell Sea, particularly for the area off the Fimbul Ice Shelf and along the coast between approx. 15°E to 10°W within a water depth range from approx. 500 m to 2500 m. Breeding Ad\'elie penguins (Pygoscelis adeliae): The map of potential foraging habitats of breeding P. adeliae is based on British Antarctic Survey (BAS) Inventory data from Phil Trathan (ID 754) and Mike Dunn and P. Trathan (ID 764, 773, 779), a dataset from BAS (P. Trathan) and Instituto Ant\'artico Argentino (Mercedes Santos) (ID 753) and a dataset from the US AMLR Program from Jefferson Hinke and Wayne Trivelpiece (NOAA) (ID 910), which are stored in the Birdlife International\textquotesingles Seabird Tracking Database (data request: 20-10-2015). Suitable foraging habitats for breeding Ad\'elies from colonies from which no tracking data were not available were approximated by a 50 km buffer and a 50-100 km ring buffer around each colony according to the recommendations of a CCAMLR MPA planning workshop. Breeding locations and estimated abundance of breeding pairs were taken from Lynch and LaRue (2014). The tracking data were processed with a state-space model described by Johnson et al. (2008) and were implemented in the R package crawl (Johnson 2011). Jefferson Hinke (NOAA) kindly provided us with support running the R script. Highly suitable foraging habitats occurred about 50 km away from the colonies on King Georg Island, the colony in Hope Bay (Graham Land) and the colonies on the South Orkney Islands. Non-breeding Ad\'elie penguins (Pygoscelis adeliae): The map of potential foraging habitats of non-breeding P. adeliae is based on British Antarctic Survey (BAS) Inventory data from Phil Trathan (ID 754) and Mike Dunn and P. Trathan (ID 773, 779), a dataset from BAS (P. Trathan) and Instituto Ant\'artico Argentino (Mercedes Santos) (ID 753) and a dataset from the US AMLR Program from Jefferson Hinke and Wayne Trivelpiece (NOAA) (ID 910), which are stored in the Birdlife International\textquotesingles Seabird Tracking Database (data request: 20-10-2015). The tracking data were processed with a state-space model described by Johnson et al. (2008) and were implemented in the R package crawl (Johnson 2011). Jefferson Hinke (NOAA) kindly provided us with support running the R script. Highest habitat utilisation was concentrated in relative small areas (e.g., close to King Georg Island). However, the non-breeding Ad\'elies seemed to roam through large parts of the Weddell Sea. Emperor penguins (Aptenodytes forsteri): The probability map of A. forsteri occurrence was developed as a function of distance to colony and colony size from Fretwell et al. (2012, 2014) as well as from sea ice concentration from AMSR-E sea ice maps. Our model of emperor penguin foraging distribution during breeding season showed that the probability of occurrence is highest at the Halley and Dawson colony near Brunt Ice Shelf and at the Atka colony near Ekstrøm Ice Shelf. More information on the spatial analysis is given in working paper WG-EMM-16/03 and WG-SAM-17/30 (for T. antarctica) submitted to the CCAMLR Working Group on Ecosystem Monitoring and Management (EMM) and the CCAMLR Working Group on Statistics, Assessments and Modelling (SAM), respectively (available at https://www.ccamlr.org/en/wg-emm-16 and https://www.ccamlr.org/en/wg-s
    Repository Name: EPIC Alfred Wegener Institut
    Type: Other , NonPeerReviewed
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 91
    Publication Date: 2022-09-07
    Description: Here we provide two ArcGIS map packages with georeferenced files on the spatial distribution of seals in the wider Weddell Sea (Antarctica), which were created in the context of the development of a marine protected area in the Weddell Sea. Spatial distribution of seals based on aerial surveys: The map of the spatial distribution of crabeater seals is based on modelled seal abundances from Flores et al. (2008) and Forcada et al. (2012). These modelled abundances were supplemented by abundance data derived from Bester et al. (1995, 2002) and by point data from Pl\"otz et al. (2011a-e), which were translated into abundance values by the count method for line transect data. The calculated data on seal abundances from Pl\"otz et al. (2011a-e) and Bester et al. (1995, 2002) were interpolated using the inverse distance weighted method. The combined data set of modelled and interpolated abundances showed highest absolute seal abundances offshore the Riiser-Larsen Ice Shelf and Quarisen Ice Shelf. Spatial distribution of seals based on tracking data: The map of probability of seal occurrence is based on all tracking data publicly available for the wider Weddell Sea from the MEOP data portal "Marine Mammals Exploring the Oceans Pole to Pole" (data request: 14-11-2016). In addition, we have used MEOP data (UK data: ct27, ct70; German data: ct113, wd06, wd07) for which unconditional sharing is not yet accepted. These data were provided by Lars Boehme (University of St. Andrews) and Horst Bornemann (AWI), respectively. Furthermore, the data from the MEOP data portal were complemented by tracking data sets on southern elephant seals (Tosh et al. 2009, James et al. 2012), Weddell seals (McIntyre et al. 2013) and crabeater seals (Nachtsheim et al. 2016). All tracking data united were processed with a state-space model described by Johnson et al. (2008) and were implemented in the R package crawl (Johnson 2011). The tracking data analysis indicated frequent occurrence of seals in a larger area off the Brunt and Filchner Ice Shelf (approx. 25°W-40°W), and in smaller patches along the eastern Weddell Sea ice shelfs as well as in the region around the tip of the Antarctic Peninsula. More information on the spatial analysis is given in working paper WG-EMM-16/03 and WG-SAM-17/30 submitted to the CCAMLR Working Group on Ecosystem Monitoring and Management (EMM) and the CCAMLR Working Group on Statistics, Assessments and Modelling (SAM), respectively (available at https://www.ccamlr.org/en/wg-emm-16 and https://www.ccamlr.org/en/wg-sam-17
    Repository Name: EPIC Alfred Wegener Institut
    Type: Other , NonPeerReviewed
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 92
    Publication Date: 2022-09-07
    Description: Here we provide four ArcGIS map packages with georeferenced files on the spatial distribution of Antarctic petrels, Ad\'elie penguins (breeders and non-breeders) and Emperor penguins in the wider Weddell Sea (Antarctica), which were created in the context of the development of a marine protected area in the Weddell Sea. Antarctic petrel (Thalassoica antarctica): We approximated potential foraging habitats of T. antarctica according to existing literature by ice coverage from AMSR-E sea ice maps, bathymetric data from the International Bathymetric Chart of the Southern Ocean (IBCSO), and seawater temperature data from the Finite Element Sea Ice - Ocean Model (FESOM) provided by R. Timmermann (AWI). Subsequently, we combined our Antarctic petrel model with the kernel utilization distribution model from Descamps et al. (2016). The authors kindly provided us with shape files showing the kernel utilization summer and winter distribution of Antarctic petrel breeding at Svarthamaren. Breeding locations and estimated number of breeding pairs were taken from van Franeker et al. (1999). Favourable habitat conditions for Antarctic petrels were predicted for the Lazarev Sea and along the eastern coast of the Weddell Sea, particularly for the area off the Fimbul Ice Shelf and along the coast between approx. 15°E to 10°W within a water depth range from approx. 500 m to 2500 m. Breeding Ad\'elie penguins (Pygoscelis adeliae): The map of potential foraging habitats of breeding P. adeliae is based on British Antarctic Survey (BAS) Inventory data from Phil Trathan (ID 754) and Mike Dunn and P. Trathan (ID 764, 773, 779), a dataset from BAS (P. Trathan) and Instituto Ant\'artico Argentino (Mercedes Santos) (ID 753) and a dataset from the US AMLR Program from Jefferson Hinke and Wayne Trivelpiece (NOAA) (ID 910), which are stored in the Birdlife International\textquotesingles Seabird Tracking Database (data request: 20-10-2015). Suitable foraging habitats for breeding Ad\'elies from colonies from which no tracking data were not available were approximated by a 50 km buffer and a 50-100 km ring buffer around each colony according to the recommendations of a CCAMLR MPA planning workshop. Breeding locations and estimated abundance of breeding pairs were taken from Lynch and LaRue (2014). The tracking data were processed with a state-space model described by Johnson et al. (2008) and were implemented in the R package crawl (Johnson 2011). Jefferson Hinke (NOAA) kindly provided us with support running the R script. Highly suitable foraging habitats occurred about 50 km away from the colonies on King Georg Island, the colony in Hope Bay (Graham Land) and the colonies on the South Orkney Islands. Non-breeding Ad\'elie penguins (Pygoscelis adeliae): The map of potential foraging habitats of non-breeding P. adeliae is based on British Antarctic Survey (BAS) Inventory data from Phil Trathan (ID 754) and Mike Dunn and P. Trathan (ID 773, 779), a dataset from BAS (P. Trathan) and Instituto Ant\'artico Argentino (Mercedes Santos) (ID 753) and a dataset from the US AMLR Program from Jefferson Hinke and Wayne Trivelpiece (NOAA) (ID 910), which are stored in the Birdlife International\textquotesingles Seabird Tracking Database (data request: 20-10-2015). The tracking data were processed with a state-space model described by Johnson et al. (2008) and were implemented in the R package crawl (Johnson 2011). Jefferson Hinke (NOAA) kindly provided us with support running the R script. Highest habitat utilisation was concentrated in relative small areas (e.g., close to King Georg Island). However, the non-breeding Ad\'elies seemed to roam through large parts of the Weddell Sea. Emperor penguins (Aptenodytes forsteri): The probability map of A. forsteri occurrence was developed as a function of distance to colony and colony size from Fretwell et al. (2012, 2014) as well as from sea ice concentration from AMSR-E sea ice maps. Our model of emperor penguin foraging distribution during breeding season showed that the probability of occurrence is highest at the Halley and Dawson colony near Brunt Ice Shelf and at the Atka colony near Ekstrøm Ice Shelf. More information on the spatial analysis is given in working paper WG-EMM-16/03 and WG-SAM-17/30 (for T. antarctica) submitted to the CCAMLR Working Group on Ecosystem Monitoring and Management (EMM) and the CCAMLR Working Group on Statistics, Assessments and Modelling (SAM), respectively (available at https://www.ccamlr.org/en/wg-emm-16 and https://www.ccamlr.org/en/wg-s
    Repository Name: EPIC Alfred Wegener Institut
    Type: Other , NonPeerReviewed
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 93
    Publication Date: 2022-09-07
    Description: Here we provide two ArcGIS map packages with georeferenced files on the spatial distribution of seals in the wider Weddell Sea (Antarctica), which were created in the context of the development of a marine protected area in the Weddell Sea. Spatial distribution of seals based on aerial surveys: The map of the spatial distribution of crabeater seals is based on modelled seal abundances from Flores et al. (2008) and Forcada et al. (2012). These modelled abundances were supplemented by abundance data derived from Bester et al. (1995, 2002) and by point data from Pl\"otz et al. (2011a-e), which were translated into abundance values by the count method for line transect data. The calculated data on seal abundances from Pl\"otz et al. (2011a-e) and Bester et al. (1995, 2002) were interpolated using the inverse distance weighted method. The combined data set of modelled and interpolated abundances showed highest absolute seal abundances offshore the Riiser-Larsen Ice Shelf and Quarisen Ice Shelf. Spatial distribution of seals based on tracking data: The map of probability of seal occurrence is based on all tracking data publicly available for the wider Weddell Sea from the MEOP data portal "Marine Mammals Exploring the Oceans Pole to Pole" (data request: 14-11-2016). In addition, we have used MEOP data (UK data: ct27, ct70; German data: ct113, wd06, wd07) for which unconditional sharing is not yet accepted. These data were provided by Lars Boehme (University of St. Andrews) and Horst Bornemann (AWI), respectively. Furthermore, the data from the MEOP data portal were complemented by tracking data sets on southern elephant seals (Tosh et al. 2009, James et al. 2012), Weddell seals (McIntyre et al. 2013) and crabeater seals (Nachtsheim et al. 2016). All tracking data united were processed with a state-space model described by Johnson et al. (2008) and were implemented in the R package crawl (Johnson 2011). The tracking data analysis indicated frequent occurrence of seals in a larger area off the Brunt and Filchner Ice Shelf (approx. 25°W-40°W), and in smaller patches along the eastern Weddell Sea ice shelfs as well as in the region around the tip of the Antarctic Peninsula. More information on the spatial analysis is given in working paper WG-EMM-16/03 and WG-SAM-17/30 submitted to the CCAMLR Working Group on Ecosystem Monitoring and Management (EMM) and the CCAMLR Working Group on Statistics, Assessments and Modelling (SAM), respectively (available at https://www.ccamlr.org/en/wg-emm-16 and https://www.ccamlr.org/en/wg-sam-17
    Repository Name: EPIC Alfred Wegener Institut
    Type: Other , NonPeerReviewed
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 94
    Publication Date: 2023-06-21
    Repository Name: EPIC Alfred Wegener Institut
    Type: PANGAEA Documentation , notRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 95
  • 96
    Publication Date: 2020-02-12
    Description: The airborne laser scanning (ALS) datasets were acquired at the Arctic tundra site of Trail Valley Creek (TVC), Northwest Territories, Canada, which is underlain by continuous permafrost. Basic processing and filtering steps were applied to the ALS point cloud. Based on a classification into ground and vegetation points, a Digital Terrain Model (DTM) and rasters of mean and maximum vegetation heights are derived. Detailed metadata are included.
    Language: English
    Type: info:eu-repo/semantics/workingPaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 97
    Publication Date: 2018-01-02
    Description: Energies, Vol. 11, Pages 44: Transient Stability Analysis of Islanded AC Microgrids with a Significant Share of Virtual Synchronous Generators Energies doi: 10.3390/en11010044 Authors: Chang Yuan Peilin Xie Dan Yang Xiangning Xiao As an advanced control method that could bring extra inertia and damping characteristics to inverter-based distributed generators, the virtual synchronous generator (VSG) has recently drawn considerable attention. VSGs are expected to enhance the frequency regulation capability of the local power grid, especially the AC microgrid in island mode. However, the cost of that performance promotion is potential instability. In this paper, the unstable phenomena of the islanded microgrid dominated by SGs and distributed generators (DSs) are addressed after mathematical modeling and detailed eigenvalue analyses respectively. The influence of VSG key parameters, e.g., virtual inertia, damping factor, and droop coefficient on system stability is investigated, and the corresponding mathematical calculation method of unstable region is obtained. The theoretical analysis is well supported by time domain simulation results. The predicted frequency oscillation suggests the consideration of stability constrain during the VSG parameters design procedure.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
    Published by MDPI Publishing
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 98
    Publication Date: 2018-01-02
    Description: Energies, Vol. 11, Pages 77: Anisotropy in Thermal Recovery of Oil Shale—Part 1: Thermal Conductivity, Wave Velocity and Crack Propagation Energies doi: 10.3390/en11010077 Authors: Guoying Wang Dong Yang Zhiqin Kang Jing Zhao In this paper, the evolution of thermal conductivity, wave velocity and microscopic crack propagation both parallel and perpendicular to the bedding plane in anisotropic rock oil shale were studied at temperatures ranging from room temperature to 600 °C. The results show that the thermal conductivity of the perpendicular to bedding direction (KPER) (PER: perpendicular to beeding direction), wave velocity of perpendicular to bedding diretion (VPER), thermal conduction coefficient of parallel to beeding direction (KPAR) and wave velocity of parallel to beeding direction (VPAR) (PAR: parallel to bedding direction) decreased with the increase in temperature, but the rates are different. KPER and VPER linearly decreased with increasing temperature from room temperature to 350 °C, with an obvious decrease at 400 °C corresponding to a large number of cracks generated along the bedding direction. KPER, VPER, KPAR and VPAR generally maintained fixed values from 500 °C to 600 °C. 400 °C has been identified as the threshold temperature for anisotropic evolution of oil shale thermal physics. In addition, the relationship between the thermal conductivity and wave velocity based on the anisotropy of oil shale was fitted using linear regression. The research in this paper can provide reference for the efficient thermal recovery of oil shale, thermal recovery of heavy oil reservoirs and the thermodynamic engineering in other sedimentary rocks.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
    Published by MDPI Publishing
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 99
    Publication Date: 2018-01-02
    Description: Energies, Vol. 11, Pages 64: Practical On-Board Measurement of Lithium Ion Battery Impedance Based on Distributed Voltage and Current Sampling Energies doi: 10.3390/en11010064 Authors: Xuezhe Wei Xueyuan Wang Haifeng Dai Battery impedance based state estimation methods receive extensive attention due to its close relation to internal dynamic processes and the mechanism of a battery. In order to provide impedance for a battery management system (BMS), a practical on-board impedance measuring method based on distributed signal sampling is proposed and implemented. Battery cell perturbing current and its response voltage for impedance calculation are sampled separately to be compatible with BMS. A digital dual-channel orthogonal lock-in amplifier is used to calculate the impedance. With the signal synchronization, the battery impedance is obtained and compensated. And the relative impedance can also be obtained without knowing the current. For verification, an impedance measuring system made up of electronic units sampling and processing signals and a DC-AC converter generating AC perturbing current is designed. A type of 8 Ah LiFePO4 battery is chosen and the valuable frequency range for state estimations is determined with a series of experiments. The battery cells are connected in series and the impedance is measured with the prototype. It is shown that the measurement error of the impedance modulus at 0.1 Hz–500 Hz at 5 °C–35 °C is less than 4.5% and the impedance phase error is less than 3% at <10 Hz at room temperature. In addition, the relative impedance can also be tracked well with the designed system.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
    Published by MDPI Publishing
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 100
    Publication Date: 2018-01-02
    Description: Energies, Vol. 11, Pages 80: Well Test Analysis for Fractured and Vuggy Carbonate Reservoirs of Well Drilling in Large Scale Cave Energies doi: 10.3390/en11010080 Authors: Cuiqiao Xing Hongjun Yin Kexin Liu Xingke Li Jing Fu A well test analysis model for fractured and vuggy carbonate reservoir of wells drilling in large scale cave considering wellbore storage and skin factor is established in this paper. The Laplace transformation and Stehfest numerical inversion are applied to obtain the results of wellbore pressure. Through the sensitivity analysis of different parameters for the well test typical curves, it is found that the change of the well test curves is in accordance with the theoretical analysis. With the increase of skin factor, the hump of well test typical curves is steeper. The storage ratio influences the depth and width of the concave in the pressure derivative curves. The cross flow coefficient mainly affects the position of the concave occurrence in the pressure derivative curves. The dimensionless reservoir radius mainly affects the middle and late stages of the log-log pressure type curves, and the later well test curves will be upturned for sealed boundary. The duration of the early stage of the log-log curves will become longer when drilling in large scale cave. The effective well radius is increased to a certain extent, which is in full agreement with the conclusions in this paper. The size of the caves has the same effect on the well test typical curves as wellbore storage coefficient. Due to acidification, fracturing, and other reasons, the boundary of the cave will collapse. Therefore, considering the wellbore storage coefficient and skin effect is very important during well testing. However, the existing models for well testing of fractured and vuggy carbonate reservoir often ignore the wellbore storage coefficient and skin effect. For fractured and vuggy carbonate reservoirs of well drilling in large scale cave, the existing models are not applicable. Since the previous models are mostly based on the triple-porosity medium and the equivalent continuum. The well test model for well drilling in large scale cave of fracture-cavity carbonate reservoirs with wellbore storage coefficient and skin factor in this work has significant application value for oil field.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
    Published by MDPI Publishing
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...