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Abstract: The dataset compiles in situ observational data obtained during the PHYTO-FRONT cruise (2014-02-03 - 2014-02-07) of central-southern Chile. The data includes conductivity, temperature, depth and potential density. Nutrient data, total and size-fractionated chlorophyll a measurements and data from plankton samples for composition and abundance of the micro-phytoplankton (microdiatoms) size fraction are also included. Category: geoscientificInformation Source: Not Available Supplemental Information: Not Availble Coverage: Not Available
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  • Other
Abstract: The data comprise sample locations and results of grain size measurements and optically stimulated luminescence dating of sediments from the Orog Nuur Basin (southern Mongolia). Samples were taken in order to gain a comprehensive sedimentological and geochronological overview over late Quaternary sediment cascades and respective archives. Grain size measurements were conducted in Aachen using a Beckmann Coulter Laser Particle Sizer. OSL data were obtained in the Luminescence lab of Cologne University. Samples were classified into 7 sediment archives according to the field description and grain size analysis (fluvial, beach ridge, lacustrine, littoral sand, dune sand, basin silty sands, and mountain silt). The grain size statistics is presented in the .xlsx-table according to this classification. The combination of sedimentological, geomorphologic and geochronological observations led to a late Quaternary landscape reconstruction, including alluvial fan evolution, lake level history and aeolian dynamics in this arid region of the northern Gobi Desert. Category: geoscientificInformation Source: Not Available Supplemental Information: Not Availble Coverage: EVENT LABEL: * LATITUDE: 45.030000 * LONGITUDE: 100.730000 * METHOD/DEVICE: Multiple investigations
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Abstract: Threats to biodiversity pose an enormous challenge for Africa. Mounting social and economic demands on natural resources increasingly threaten key areas for conservation. Effective protection of sites of strategic conservation importance requires timely and highly detailed geospatial monitoring Larger ecological zones and wildlife corridors warrant monitoring as well, as these areas have an even higher degree of pressure and habitat loss. To address this, a satellite imagery based monitoring workflow to cover at-risk areas at various details was developed. During the program's first phase,a total of 560,442km2 area in Sub-Saharan Africa was covered, from which 153,665km2 were mapped with 8 land cover classes while 406,776km2 were mapped with up to 32 classes. Satellite imagery was used to generate dense time series data from which we derived thematic land cover maps. Each map and change map were fully verified and validated by an independent team to achieve our strict data quality requirements. The independent validation datasets for each KLCs are also described and presented here. Category: geoscientificInformation Source: Not Available Supplemental Information: Not Availble Coverage: EVENT LABEL: * LATITUDE: 7.200000 * LONGITUDE: 21.100000 * LOCATION: Africa * METHOD/DEVICE: Satellite derived
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Abstract: Not Available Category: geoscientificInformation Source: Not Available Supplemental Information: Not Availble Coverage: EVENT LABEL: * LATITUDE: 45.050000 * LONGITUDE: 100.510000 * METHOD/DEVICE: Multiple investigations
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Abstract: Not Available Category: geoscientificInformation Source: Not Available Supplemental Information: Not Availble Coverage: EVENT LABEL: * LATITUDE: 45.050000 * LONGITUDE: 100.510000 * METHOD/DEVICE: Multiple investigations
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Abstract: The database consists of two shapefiles that show the locations of unmanned aerial vehicle (UAV) surveys and of ground-penetrating-radar analyses. The raw data of these surveys may be shared upon request and after publication. Additionally, one shapefile consisting of geomorphological alluvial fan mapping has been added. UAV surveys were conducted with the DJI Phantom 4 (12 MP sensor) and DJI Phantom 4 Advanced (20 MP sensor) drones to create high-resolution digital elevation models (DEMs). In the 'Drone_areas' shapefile, the column 'Name' refers to the survey name given in the field, and the column 'Reference' indicates the catchment referred to in van der Wal et al. (submitted to Geomorphology in 2019). The 'GPR_profiles' shapefile includes the locations of all GPR data collected in September 2017. All measurements were conducted using a SIR-3000 field computer and a 100 MHz GSSI radar antenna (model 3207A), with a survey wheel (model 620) to calibrate distance data. Dielectric permittivity values were set between 4 and 7. Van der Wal et al. (submitted to Geomorphology in 2019) includes GPR profiles 005, 003, 006 (G-1, G-2, G-3, respectively) and 064 (Hustiyn am). The 'AlluvialFanLevels' shapefile includes a geomorphological map of alluvial fans along the Ikh Bogd mountain front. The method for mapping is discussed in van der Wal et al. (submitted to Geomorphology in 2019). Some minor alluvial fan levels were excluded from publication (e.g. levels 1+ and 1t) because of their minor scale and lack of relevance in the discussed context. Category: geoscientificInformation Source: Not Available Supplemental Information: Not Availble Coverage: EVENT LABEL: * LATITUDE: 45.050000 * LONGITUDE: 100.510000 * METHOD/DEVICE: Multiple investigations
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Abstract: In this study, we measured the relative transcript expression of 45 target genes and 3 normalizer genes in the liver of 120 Atlantic salmon that were subjected to 3 different climate scenarios in a tank-based system. Atlantic salmon were exposed to following treatments: (1) Control (CT) constant temperature of 12°C and 100 % air saturation; (2) Warm&Normoxic (WN) incremental temperature increase (1°C per week from 12 - 20°C) at 100% air saturation; and (3) Warm&Hypoxic (WH) decrease in oxygen content of 70% air saturation over one week, followed by two weeks of acclimation to this oxygen level, and then incremental temperature increase (1°C per week from 12 - 20°C) at 70% air saturation. Liver samples were taken from 8 fish per treatment group (CT, WN and WH) at 5 different temperature measuring points: 12°C, 16°C, 18°C, 19°C, and 20°C. For each treatment group, we used 8 biological fish replicates (4 fish from 2 tank replicates). The sampling during the simulated seasonal temperature increase was performed 3 days after reaching the temperature level of interest (12°C-initial, 16°C-3days, 18°C-3days, 19°C-3days, 20°C-3days). Once the maximum temperature increase of 20°C was reached, an additional sampling after 4 weeks at 20°C was carried out (20°C-4weeks). After each temperature challenge eight fish per per tank replicate (n = 8, N = 24) were euthanized with 400 mg L^-1 of tricaine-methane-sulfonate. Liver tissues (100 mg per sample) were rapidly dissected from fish, placed in RNase-free 1.5 mL tubes, flash-frozen in liquid nitrogen, and stored at -80°C until RNA extractions were performed. The relative transcript expression values of 45 genes of interest (GOIs) and 3 normalizers were assessed for 8 individual fish samples per 3 treatment groups at 5 sampling time points (n = 8, N = 120). Real-time qPCR Fluidigm Biomark HD system based on 96.96 dynamic arrays (GE-arrays) was employed according to the manufacturer's instructions (Fluidigm, Biomark HD). The transcript levels of 48 genes were measured in two technical replicates, while we included two no template controls (NTCs), two controls for genomic DNA contamination (no-reverse transcription 'no-RT') and two linker samples for inter-run and between-run calibration. In this data submission file, we provide the 'mean threshold cycle (CT) values' for 45 GOIs and 3 normalizer genes that were calculated from two technical replicates and were measured with GE-fast 96.96 PCR protocol and Fluidigm Biomark HD system. This experiment was performed as part of the project 'Mitigating the Impacts of Climate-Related Challenges on Salmon Aquaculture (MICCSA)' between the years 2017-2020. Category: geoscientificInformation Source: Not Available Supplemental Information: Not Availble Coverage: Not Available
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Abstract: Geochemically distinct volcanic ash (tephra) deposits are increasingly acknowledged as a key geochronological tool to synchronize independent paleoclimate archives. Recent advances in the detection of invisible (crypto) tephra have led to the ongoing establishment, development and integration of regional tephra lattices. These frameworks offer an overview of the spatial extent of geochemically characterized tephra from dated eruptions – a valuable tool for precise correlation of paleorecords within these areas. Here, we harness cryptotephra analysis to investigate the occurrence of two well-known tephra markers from the Last Glacial Period (i.e. FMAZ II-1 (26.7 ka b2k) and NAAZ II (II-RHY-1) (55.3 ka b2k)), in marine sediment cores from the Nordic, Irminger and Labrador Seas. In addition, we assess the imprint of bioturbation on two of these tephra deposits using Computed Tomography (CT) imagery. We have successfully identified FMAZ II-1 in the Nordic and Irminger Seas. The tephra deposit is a visible deposit in the Nordic Seas, whereas it appears as a single high concentration peak within the fine-grained shard size fraction (i.e. 25-80 μm) in the Irminger Sea. Both horizons are primary airfall deposits, and this study is the first to identify a FMAZ II-1 deposit of isochronous nature in the Irminger Sea region. In addition, we have identified a new tephra horizon in the Irminger Sea, which is stratigraphically associated with FMAZ II-1, and geochemically similar to the known 2-JPC-192-1 population. We discuss its potential to serve as a new reference tie-point for correlations in the region. Lastly, we have successfully identified NAAZ II (II-RHY-1) of isochronous nature in both the Irminger and Labrador Sea. The layers are interpreted to be deposited by either direct airfall or by sea-ice drifting past the sites. Compared to the existing frameworks, which previously mainly focused on sites east of Iceland, our findings expand the knowledge and utility of the FMAZ II-1 and NAAZ II (II-RHY-1) horizons. This dataset contains down core shard concentrations and major element oxide data of tephra layers FMAZ II (from cores MD99-2284 and GS16-204-18CC) and NAAZ II (II-RHY-I) (from cores GS16-204-22CC-A and GS16-204-18CC). Category: geoscientificInformation Source: Not Available Supplemental Information: Not Availble Coverage: Not Available
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Abstract: Our knowledge about hydrothermally active seamounts is limited to few examples. Here, we provide evidence for recent hydrothermal circulation at an alleged Cretaceous volcano near the active end of the Canary Island hotspot. Parts of its summit area are densely covered by shell fragments from vesicomyid clams and some living chemoautotroph organisms, indicating ongoing hydrothermal activity since some thousands or tens of thousand years. The recovery of fresh glassy basalt from the summit suggests that a pulse of rejuvenated volcanism has provided the driving heat. Heat flow values from the surrounding seafloor (49±7 mW/m2) are close to the expected background for conductively cooled crust, but an increase towards the seamount flanks likely reflects fluid circulation. Our study suggests that formation of numerous small monogenetic or rarely erupting seamounts may have given rise to ephemeral hydrothermal systems and related marine ecosystems, which may be of global relevance. Category: geoscientificInformation Source: Not Available Supplemental Information: Not Availble Coverage: Not Available
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Abstract: This data publication contains sea-surface temperatures and diatom abundances and biometry in sediment core DCR-1PC from the southwestern Indian sector of the Southern Ocean over the last 350,000 years. Core DRC1-PC was retrieved during the oceanographic expedition Hakuho-maru KH-10-7 during the austral summer 2010-2011. Diatom census counts and diatom biometry were performed in 2018-2019 to investigate the potential impact of climate degradation on Hemisdicus karstenii disappearance at ~190 ka. Included are relative abundances (RA in % of the total diatom assemblages) and absolute abundances (AA in millions of valve per gram of dry sediment) of Hemidiscus karstenii (Hk) and Fragilariopsis kerguelensis (Fk). Summer sea-surface temperatures (January to March) were estimated by applying the Modern Analog Technique (MAT) to fossil diatom assemblages. Hk and Fk biometry versus depth and age are also included. For each depth, mean length results from measurements of 100 different and complete valves of both Hk and Fk on which within-sample standard deviations were calculated. Category: geoscientificInformation Source: Not Available Supplemental Information: Not Availble Coverage: Not Available
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