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The iron-snow regime in Fe-FeS cores: a numerical and experimental approach

In the Earth, the dynamo action is strongly linked to core freezing. There is a solid inner core, the growth of which provides a buoyancy flux that drives the dynamo. The buoyancy in this case derives from a difference in composition between the solid inner core and the fluid outer core. In planetary bodies smaller than the Earth, however, this core differentiation process may differ - Fe may precipitate at the core-mantle boundary (CMB) rather than in the center and may fall as iron snow and initially remelt with greater depth. A chemical stable sedimentation zone develops that comprises with time the entire core - at that time a solid inner core starts to grow. The dynamics of this system is not well understood and also whether it can generate a magnetic field or not. The Jovian moon Ganymede, which shows a present-day magnetic dipole field, is a candidate for which such a scenario has been suggested. We plan to study this Fe-snow regime with both a numerical and experimental approach. In the numerical study, we use a 2D/3D thermo-chemical convection model that considers crystallization and sinking of iron crystals together with the dynamics of the liquid core phase (for the 3D case the influence of the rotation of the Fe snow process is further studied).The numerical calculations will be complemented by two series of experiments: (1) investigations in metal alloys by means of X-ray radioscopy, and (2) measurements in transparent analogues by optical techniques. The experiments will examine typical features of the iron snow regime. On the one hand they will serve as a tool to validate the numerical approach and on the other hand they will yield important insight into sub-processes of the iron snow regime, which cannot be accessed within the numerical approach due to their complexity.

Öffentliche Bekanntmachung nach § 5 UVPG I Änderung einer Anlage zum Halten von Sauen einschließlich dazugehörender Ferkelaufzuchtplätze

Gegenstand des Antrages ist die Umstrukturierung der bestehenden Tierhaltungsanlage durch die Errichtung eines Abferkelstalles mit Biofilter (BE 15), eines Außenklimastalles für Sauen (BE 13), einer Halle mit Fahrsilo (BE 14) und einer überdachten Festmistplatte (BE 16) sowie durch den Rückbau bestehender Anlagen (Güllehochbehälter (BE 5) und zwei Lagerhallen (BE 6 und 7)). Im Rahmen der Neuerrichtung von zwei Ställen werden Teile des bisherigen Tierbestands aus den Ställen BE 3 und BE 4 in die neu errichteten Ställe umgestallt. Dadurch wird der Tierbestand in den bestehenden Sauenställen reduziert und der verfügbare Platz pro Sau erhöht. Die BE 9, 10 und 11 bleiben unverändert. Die Umsetzung des Vorhabens erfolgt ohne Erhöhung der Tierplatzzahlen.

Results of palynological analysis from 2020 of the varved MO-05 core from Lake Mondsee (Austria) section (249-526 cm)

This study reports a precisely dated pollen record with a 20-year resolution from the varved sediments of Lake Mondsee in the north-eastern European Alps (47°49′N, 13°24′E, 481 m above sea level). The analysed part of core spans the interval between 1500 BCE and 500 CE and allows changes in vegetation composition in relation to climatic changes and human activities in the catchment to be inferred. Intervals of distinct but modest human impact are identified at ca. 1450-1220, 740-490 and 340-190 BCE and from 80 BCE to 180 CE. While the first two intervals are synchronous with prominent salt mining phases during the Bronze Age and Early Iron Age at the nearby UNESCO World Heritage Site of Hallstatt, the last two intervals fall within the Late Iron Age and Roman Imperial Era, respectively. Comparison with published records of extreme runoff events obtained from the same sediment core shows that human activities (including agriculture and logging) around Lake Mondsee were low during intervals of high flood frequency as indicated by a higher number of intercalated detrital event layers, but intensified during hydrologically stable intervals. Comparison of the pollen percentages of arboreal taxa with the stable oxygen isotope and potassium ion records of the NGRIP and GISP2 ice cores from Greenland reveals significant positive correlations for Fagus and negative correlations for Betula and Alnus. This underlines the sensitivity of vegetation around Lake Mondsee to temperature fluctuations in the North Atlantic as well as to moisture fluctuations controlled by changes in the intensity of the Siberian High and the North Atlantic Oscillation (NAO) regime.

Water isotope time series (March 2020 - March 2021) of samples collected at A. P. Møller Skolen, Kleine Breite, Schlei

Time series of stable isotopes (δ2H and δ18O) were analyzed in water samples collected near the A. P. Møller Skolen, Schleswig (Kleine Breite, Schlei), in biweekly to monthly intervals between March 2020 and March 2021. Water was sampled with a pipette from ca. 0.5 m below water surface and directly transferred into a measurement vial. Isotope analysis was conducted at IGB Berlin, using a Picarro L2130-i cavity ring-down spectrometer. Water chemical parameters were measured in-situ with a modular WTW 3440 multiparameter devices and regularly calibrated conductivity cells (MPP 930 IDS, TetraCon® 925-P). The data give information about the seasonal isotope amplitude at the sampled locations and about spatial variability along the transects.

Water isotope time series (March 2020 - March 2021) of samples collected in Kloster, Hiddensee

Time series of stable isotopes (δ2H and δ18O) were analyzed in water samples taken near the harbour of Kloster (Hiddensee), in biweekly to monthly intervals between March 2020 and March 2021. Water was sampled with a pipette from ca. 0.5 m below water surface and directly transferred into a measurement vial. Isotope analysis was conducted at IGB Berlin, using a Picarro L2130-i cavity ring-down spectrometer. Water chemical parameters were measured in-situ with WTW multiparameter measurement devices. The data give information about the seasonal isotope amplitude at the sampled locations and about spatial variability along the transects.

Stable Water Isotopologue data collected during HCCT-2010

Cloud samples for the isotopic analysis were collected in the framework of the Hill Cap Cloud Thuringia 2010 (HCCT-2010) campaign on Schmücke (50° 39'N/ 10° 46'E, 937 m a.s.l.; Germany) in September and October 2010 with a three-stage Caltech Active Strand Cloudwater Collector (CASCC) during 13 different cloud events with a temporal resolution of 1 to 3 hours. In a first step, we ensured that no additional fractionation occurred during sampling with the CASCC. The d values of the three sizes classes of the CASCC (4 µm to 16 µm, 16 µm to 22 µm and >22 µm) did not differ significantly, revealing that the cloud droplets of different sizes quickly equilibrate their delta value with the one of the surrounding vapor. delta values in the cloud droplets varied from -77 per mil to -15 per mil in d2H and from -12.1 per mil to -3.9 per mil in d18O and were fitted by d2H =7.8*d18O +13*10**-3. delta values decreased with temperature as well as towards the end of the campaign, representing a seasonal trend which is known from d values in precipitation. The deuterium excess of the cloud samples was generally higher than the Local Meteoric Water Line of the closest GNIP (Global Network of Isotopes in Precipitation) station. Rain decreases its deuterium excess during falling through an unsaturated air column, while the cloud droplets conserve the deuterium excess of the initial evaporation and thus have been found to be a good indicator for the airmass source region: higher deuterium excess was measured for polar air masses and lower deuterium excess for Mediterranean air masses. Changes in d values during one cloud event were up to 3.6 per mil (d2H) and 0.23 per mil (d18O), except for frontal passages, which were associated with increases of ~6 per mil per hour (d2H) and ~0.6 per mil per hour (d18O). Using a box model, we showed that the influence of condensation only was able to explain the variation in the isotope signal of two cloud passages. Consequently, we deduced that the water vapor "feeding" the cloud advected the measured changes. A trajectory analysis and moisture source diagnostic revealed that it is very likely that the variations were either related to rain out along the trajectories or to meteorological changes in the moisture source region. This was the first study using stable water isotopologues in cloud water manifesting their potential in the context of atmospheric water vapor circulation.

Water isotope values from estuarine systems along the German Baltic Sea coast

Stable isotopes (δ²H and δ¹⁸O) were analyzed in water samples collected at the German Baltic Sea Coast. Transect samples were taken in June 2019, March 2020, and July 2021 at 68 spots along the Schlei, the Zingster Bodden chain, and the Rügener and Greifswalder Boddens. Additionally, at selected spots time series were sampled in biweekly to monthly intervals between March 2020 and March 2021. At shores, water was sampled with a pipette from 0.3 to 0.6 m below water surface and directly transferred into a measurement vial. In deeper parts of the boddens a Limnos sampler was used to obtain water from 0.5 to 1 m below surface. Isotope analysis was conducted at IGB Berlin, using a Picarro L2130-i cavity ring-down spectrometer. The measurement uncertainty was quantified by error propagation, including the parameters a) uncertainties of lab standards; b) errors of standard calibration; c) average standard deviation of replicate measurements. Based on this, measurement uncertainty was estimated to account 0.16 ‰ for δ¹⁸O and 0.57 ‰ for δ²H. Water chemical parameters were measured with WTW measurement devices. The data give information about a) the seasonal isotope amplitude at the sampled locations; b) spatial variability along the transects, and c) the correlation between isotopes and water chemical parameters.

Benthic biogeochemistry data from RV HEINCKE cruise HE582 to the German Bight, North Sea in late summer 2021

This dataset contains data from the RV Heincke cruise HE582 to the German Bight of the North Sea in late summer 2021. The aim of the research was to investigate the source of sedimentary glycan concentrations in subtidal sandy sediments. Glycans represent a substantial fraction of extracellular polymeric substances and may affect flow dynamics in marine sandy sediments. The origin and concentration of glycans in sands remain understudied until today. To gain insights into oxygen supply and glycan concentrations in sandy sediment, we conducted in situ measurements and sampled sediment via a van Veen grab for ex situ investigations. Oxygen penetration depths were determined by a benthic lander, which was deployed for ca. 24h at each station. Chlorophyll a concentrations as an indicator for potentially photosynthetically active sedimentary biomass were derived via extraction with 90% acetone against Sigma Aldrich standards. Glycan concentrations served as indicator for extracellular polymeric substances and were quantified against a glucose standard curve via a phenol sulfuric acid assay after prior sequential glycan extraction (MilliQ, EDTA, NaOH). The final glycan concentrations are referred to per volume of porespace, and therefore given in mmol/l porewater. To investigate if benthic primary producers could be responsible for the extracted sedimentary glycan concentrations, we conducted stable isotope incubations.

Datenarchiv Sondermessungen in Mecklenburg-Vorpommern

Zur Erfassung der Luftqualität in Mecklenburg-Vorpommern werden an ausgewählten Standorten Sondermessprogramme durchgeführt. U.a. handelt es sich um Sondermessprogramme zur Ermittlung der Immissionsbelastung im Rostocker Stadtgebiet, zur Beurteilung der Verkehrsimmissionen an verschiedenen Standorten in M-V, zur Ermittlung von Ammoniakimmissionen und Nährstoffeinträgen in der Nähe von Tierhaltungsanlagen und zur Ermittlung der Feinstaubimmissionen (zeitliche Entwicklung und Ursachen) in M-V. Der Datenbestand setzt sich aus kontinuierlichen und diskontinuierlich gewonnenen Messdaten der Hauptluftschadstoffe - Schwebstaub, Feinstaub (PM10), Schwefeldioxid, Kohlenmonoxid, Stickstoffmonoxid, Stickstoffdioxid, Ozon, Benzol, Toluol, Ruß und Ammoniak zusammen. Dabei handelt es sich um Messdaten, die aus zusätzlich durchgeführten Messprogrammen gewonnen wurden. U.a. wurden Messdaten mit einem Messwagen an verschiedenen Standorten in M-V ermittelt. An verschiedenen ländlichen Standorten wird die NH3-Konzentration bestimmt. Es werden Messprogramme zur Ermittlung der Verkehrsimmissionen an verschiedenen Standorten in M-V durchgeführt (u.a. zur Ermittlung sogenannter "hot spots").

Interoperabler INSPIRE View-Service: Agricultural And Aquaculture Facilities / Tierhaltungsanlagen nach BImSchG in Brandenburg - Interoperabler INSPIRE View-Service (WMS-AF-TIERE)

Der interoprable INSPIRE-Viewdienst (WMS) Agricultural and Aquaculture Facilities gibt einen Überblick über die Tierhaltungs- und Aufzuchtanlagen im Land Brandenburg. Der Datensatz umfasst Geflügel, Rinder, Kälber, Schweine und gemischte Bestände. Die Datenquelle ist das Anlageninformationssystem LIS-A. Gemäß der INSPIRE-Datenspezifikation Agricultural and Aquaculture Facilities (D2.8.III.9_v3.0) liegen die Inhalte INSPIRE-konform vor. Der WMS beinhaltet 2 Layer: AgriculturalHolding und Sites. Der Holding-Layer wird gem. INSPIRE-Vorgaben nach Wirstschaftszweigen (NACE-Kategorie "A") untergliedert in: - AF.GrowingOfPerennialCrops: Anbau mehrjähriger Pflanzen (NACE-Kategorie "A.01.2") - AF.AnimalProduction: Tierhaltung (NACE-Kategorie "A.01.4") - AF.MixedFarming: Gemischte Landwirtschaft (NACE-Kategorie "A.01.5")

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