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Experimentelle Studie der Wechselwirkung der Atmosphäre mit Polynjen und Meereis in Grönland (IKAPOS)

Das Projekt "Experimentelle Studie der Wechselwirkung der Atmosphäre mit Polynjen und Meereis in Grönland (IKAPOS)" wird vom Umweltbundesamt gefördert und von Universität Trier, Fachbereich VI Raum- und Umweltwissenschaften, Fach Umweltmeteorologie durchgeführt. Processes of the exchange of energy and momentum at the sea-ice/ocean/atmosphere interface are key processes for the polar climate system. Heat and moisture fluxes are strongly modulated by open water fractions associated with polynyas, having important consequences for the atmosphere, ocean processes, ice formation, brine release, gas exchange and biology. The project aims at the study of the atmospheric processes forcing and maintaining polynyas in the Greenland area. The study will focus on the interaction between the katabatic wind system and the sea-ice/ocean system in the coastal area of north and northwest Greenland, and on the atmosphere/sea-ice/ocean exchange processes over the North Water Polynya (NOW). The main tool of the experimental study will be the polar aircraft of the Alfred-Wegener Institute (AWI). The experiment will be carried out in coordination with AWI and with the Canadian ArcticNet program, and is part of the International Polar Year (IPY). The data of the experiment will be used for the validation of model simulations and parameterisations.

Effects of water content, input of roots and dissolved organic matter and spatial inaccessibility on C turnover & determination of the spatial variability of subsoil properties

Das Projekt "Effects of water content, input of roots and dissolved organic matter and spatial inaccessibility on C turnover & determination of the spatial variability of subsoil properties" wird vom Umweltbundesamt gefördert und von Universität Kassel, Lehr- und Forschungsgebiet Umwelt- und Lebensmittelwissenschaften, Fachgebiet Umweltchemie durchgeführt. It is well established that reduced supply of fresh organic matter, interactions of organic matter with mineral phases and spatial inaccessibility affect C stocks in subsoils. However, quantitative information required for a better understanding of the contribution of each of the different processes to C sequestration in subsoils and for improvements of subsoil C models is scarce. The same is true for the main controlling factors of the decomposition rates of soil organic matter in subsoils. Moreover, information on spatial variabilities of different properties in the subsoil is rare. The few studies available which couple near and middle infrared spectroscopy (NIRS/MIRS) with geostatistical approaches indicate a potential for the creation of spatial maps which may show hot spots with increased biological activities in the soil profile and their effects on the distribution of C contents. Objectives are (i) to determine the mean residence time of subsoil C in different fractions by applying fractionation procedures in combination with 14C measurements; (ii) to study the effects of water content, input of 13C-labelled roots and dissolved organic matter and spatial inaccessibility on C turnover in an automatic microcosm system; (iii) to determine general soil properties and soil biological and chemical characteristics using NIRS and MIRS, and (iv) to extrapolate the measured and estimated soil properties to the vertical profiles by using different spatial interpolation techniques. For the NIRS/MIRS applications, sample pretreatment (air-dried vs. freeze-dried samples) and calibration procedures (a modified partial least square (MPLS) approach vs. a genetic algorithm coupled with MPLS or PLS) will be optimized. We hypothesize that the combined application of chemical fractionation in combination with 14C measurements and the results of the incubation experiments will give the pool sizes of passive, intermediate, labile and very labile C and N and the mean residence times of labile and very labile C and N. These results will make it possible to initialize the new quantitative model to be developed by subproject PC. Additionally, we hypothesize that the sample pretreatment 'freeze-drying' will be more useful for the estimation of soil biological characteristics than air-drying. The GA-MPLS and GA-PLS approaches are expected to give better estimates of the soil characteristics than the MPLS and PLS approaches. The spatial maps for the different subsoil characteristics in combination with the spatial maps of temperature and water contents will presumably enable us to explain the spatial heterogeneity of C contents.

In-situ Messungen von eiskeimbildenden Partikeln (INP) und quantitative Bestimmung von biologischen INP

Das Projekt "In-situ Messungen von eiskeimbildenden Partikeln (INP) und quantitative Bestimmung von biologischen INP" wird vom Umweltbundesamt gefördert und von Johann Wolfgang Goethe-Universität Frankfurt am Main, Institut für Atmosphäre und Umwelt durchgeführt. Die Bildung der Eis Phase in der Troposphäre stellt einen wichtigen Fokus der aktuellen Atmosphärenforschung dar. Durch heterogene Nukleation entstehen bei Temperaturen oberhalb von -37°C primäre Eiskristalle an sogenannten eiskeimbildenden Partikeln (INP, engl, ice nucleating particles). Die räumliche Verteilung der INP und deren Quellen variieren stark. In der Atmosphäre finden sich INP nur in sehr geringer Anzahlkonzentration, oft weniger als ein Partikel pro Liter, und sie stellen nur eine kleine Untergruppe des gesamten atmosphärischen Aerosols dar. Ziel dieses Antrages ist es die Anzahlkonzentrationen von eiskeimbildenden Partikeln und deren Variabilität in der Atmosphäre zu messen. Außerdem sind Laborstudien geplant, in denen unser Verständnis über die chemischen und biologischen Eigenschaften der Partikel, die die Eisbildung initiieren, verbessert werden soll. Mit dem von unserer Arbeitsgruppe entwickelten Eiskeimzahler FINCH (Fast Ice Nucleaus CHamber) sollen die atmosphärischen Anzahlkonzentrationen von INP bei verschiedenen Gefriertemperaturen und Übersättigungen an mehreren Standorten gemessen werden. Die Kopplung von FINCH mit einem virtuellen Gegenstromimpaktor (CVI, engl, counter-flow virtual impactor, Kooperation mit RP2), die während lNUIT-1 entwickelt und getestet wurde, soll nun weiter charakterisiert und Messungen damit fortgesetzt werden. Bei dieser Methode werden die Eispartikel, die in FINCH gebildet werden, von den unterkühlten Tröpfchen und inaktivierten Partikeln separiert und mit weiteren Messmethoden untersucht. In Kooperation mit RP2 und RP8 planen wir hierbei die Charakterisierung der INP mittels Größen- und Aerosolmassenspektrometer sowie die Sammlung der INP auf Filtern oder Impaktorplatten zur anschließenden Analyse mit einem Elektronenmikroskop (ESEM, engl. DFG fomi 54.011 -04/14 page 3 of 6 Environmental Scanning Electron Microscopy). Die Feldmessdaten werden von umfangreichen Laborstudien an den Forschungseinrichtungen AIDA (RP6) und LACIS (RP7) ergänzt. Dort soll das Immersionsgefrieren von verschiedenen Testpartikeln aus biologischem Material (z.B. Zellulose), porösem Material (z.B. Zeolith) und Mineralstaub mit geringem organischem Anteil im Detail untersucht werden. Des Weiteren planen wir Labormessungen, bei denen eine verbesserte Charakterisierung der Messunsicherheiten von FINCH erarbeitet werden soll. Außerdem werden regelmäßige Tests und Kalibrierungen mit FINCH durchgeführt, für die Standardroutinen festgelegt werden sollen. Um die Rolle der INP bei der Wolken- und Niederschlagsbildung sowie bei den Wolkeneigenschaften abzuschätzen, werden die gewonnenen Messergebnisse am Ende als Eingabeparameter für erweiterte Wolkenmodelle (Kooperation mit WP-M) dienen.

Engine representative internal cooling knowledge and applications (ERICKA)

Das Projekt "Engine representative internal cooling knowledge and applications (ERICKA)" wird vom Umweltbundesamt gefördert und von Rolls-Royce Deutschland Ltd & Co KG durchgeführt. The goal of ERICKA is to directly contribute to reductions in aircraft engine fuel consumption with a targeted contribution of 1Prozent reduction in SFC relative to engines currently in service. The fuel efficiency of a jet engine used for aircraft propulsion is dependent on the performance of many key engine components. One of the most important is the turbine whose efficiency has a large influence on the engine fuel consumption and hence its CO2 emissions. The turbine must operate with high efficiency in the most hostile environment in the engine. The design of turbine cooling systems remains one of the most challenging processes in engine development. Modern high-pressure turbine cooling systems invariably combine internal convection cooling with external film cooling in complex flow systems whose individual features interact in complex ways. The heat transfer and cooling processes active are at the limit of current understanding and engine designers rely heavily on empirical tools and engineering judgement to produce new designs. ERICKA will provide a means of improving turbine blade cooling technology that will reduce turbine blade cooling mass-flow relative to that required using existing technology. A reduction in cooling mass-flow leads directly to improved component and engine efficiency. The improved technology for turbine cooling developed by ERICKA will also enable low NOx combustion chambers to be included in future engines. ERICKA will undertake research to furnish better understanding of the complex flows used to internally cool rotating turbine blades. This will be achieved by: 1) Acquisition of high quality experimental data using static and rotating test facilities 2) Development of cooling design capability by enhancement of computer codes that will exploit these experimental data ERICKA groups 18 partners representing the European aero engine industry, five SMEs and a set of leading academic institutions. Prime Contractor: Rolls-Royce PLC; London; United Kingdom.

Alpine treelines in a CO2-rich and warm world

Das Projekt "Alpine treelines in a CO2-rich and warm world" wird vom Umweltbundesamt gefördert und von Eidgenössische Forschungsanstalt für Wald, Schnee und Landschaft durchgeführt. We are experimentally increasing atmospheric CO2 concentrations (+200 ppm) and temperatures (+3K) at the alpine treeline and study the response of plant growth and soil processes. First results indicate that elevated CO2 rather affects the cycling rates than C pools in plants and soils. Rationale: The strong increase in atmospheric CO2 has changed ecosystems either directly through the CO2-effects on plant growth or indirectly through its impact on temperatures. It is likely that high altitude soils will respond particularly sensitive to the ongoing climatic changes. The temperature sensitivities of most biogeochemical processes are greater in the lower temperature range. Since alpine and montane soils contain great pools of labile C they play an important role in the response and feedbacks of the overall ecosystems C balance to the changing climate. Aims: to identify how and why does tree growth change to the increasing temperatures and CO2. to estimate how the climatic changes affects the concurrence between trees, dwarf shrubs, and grasses. to quantify the response of soil C fluxes (soil respiration, DOC leaching, accumulation in different SOM pools). to estimate the response of soil microbial community. to elucidate if the new plant-derived rapidly cycling soil C fraction or the older slower cycling soil C fraction responds more sensitive to climatic warming. to estimate if warming alters the partitioning of recent assimilates between plants and soils.

Untersuchung der zeitlichen Entwicklung der Biofilmmatrix mit Hilfe der Raman-Mikroskopie (RM) und der konfokalen Laser-Scanning-Mikroskopie (CLSM)

Das Projekt "Untersuchung der zeitlichen Entwicklung der Biofilmmatrix mit Hilfe der Raman-Mikroskopie (RM) und der konfokalen Laser-Scanning-Mikroskopie (CLSM)" wird vom Umweltbundesamt gefördert und von Technische Universität München, Institut für Wasserchemie und Chemische Balneologie, Lehrstuhl für Analytische Chemie und Wasserchemie durchgeführt. Im beantragten Forschungsvorhaben soll die Raman-Mikroskopie als Untersuchungsmethode für Biofilme neben der konfokalen Laser-Scanning-Mikroskopie etabliert werden. Es soll ausgelotet werden, in wie weit die Raman-Mikroskopie in der Lage ist, ortsaufgelöst die chemische Zusammensetzung der extrazellulären polymeren Substanzen (EPS) in Biofilmen zu identifizieren. Die geplanten Untersuchungen sollen an heterotrophen Biofilmen durchgeführt werden, die unter definierten Strömungsbedingungen und mit verschiedenen Substraten kultiviert werden. Die Frühphase der Biofilmbildung ist dabei von besonderem Interesse. Welche polymeren Substanzen bereiten die Primärbesiedlung von Oberflächen vor und wie verändert sich dieser auch als 'Konditionierung beschriebene Vorgang bei variierenden Kultivierungsmedien'. Die in dieser Phase zu generierenden Ergebnisse sind im Hinblick auf eine Verhinderung der Besiedlung von Oberflächen von außerordentlich großem Interesse. Die Veränderung der chemischen Zusammensetzung der EPS-Matrix im Kultivierungsverlauf und der Einfluss von oxidierenden Desinfektionsmitteln auf die Matrix bilden einen weiteren Untersuchungsschwerpunkt im beantragten Vorhaben. Alle Fragestellungen sollen mit der Raman-Spektroskopie bearbeitet werden. Parallel sollen mit Hilfe klassischer Verfahren (Wägung und Umsatzraten) und der CLSM (Mikroorganismen und EPS-Glycokonjugate) die Biofilme charakterisiert werden. Diese Vorgehensweise macht es möglich, wirklich neue Erkenntnisse in einen geeigneten Kontext zu den bisher bekannten Struktur-Funktions-Eigenschaften von Biofilmen zu setzen.

Investigation of the removal processes of soot particles from the atomsphere

Das Projekt "Investigation of the removal processes of soot particles from the atomsphere" wird vom Umweltbundesamt gefördert und von NOAA Earth System Research Laboratory durchgeführt. During the International Polar Year of 2008, an airborne field campaign called Aerosol, Radiative, and Cloud Processes affecting Arctic Climate (ARCPAC) has been performed in order to improve the understanding of climate relevant processes playing a role in the Arctic. The climate system in the Arctic is seen to be a dynamic and complex system with many potential non-linear feedbacks both in the Arctic a well as in the global climate system. The measurements took place in the Alaskan Arctic using closely coordinated remote sensing and in situ observations from aircraft and ground sites in the vicinity of Barrow. The main focus was to investigate the efficiency of the removal of aerosol particles and particularly of Black Carbon from the atmosphere by deposition to the surface; the deposition of Black Carbon for instance decreases the albedo of the surface. Studying the composition and the origin of the air masses influencing the Arctic air in spring is also of major interest to better understand which compounds can be deposited. In order to assess these removal processes a broad set of aerosol, gas phase and microphysics instrumentation was deployed. The first results showed that the Arctic air at this period has been strongly influenced by biomass burning emissions. The concentrations were found to be comparable to the one in mega cities but with an aerosol composition dominated by the organic fraction and very high fraction of acetonitrile. Some back-trajectory studies (FLEXPART model) have shown that those biomass plumes were originating from Russia, where this year the snow melted early in the season favoring agricultural burning of lands or forest fires. This shows the strong impact of biomass combustion pollutants transported to the Arctic and thus the potential increase of deposition of particles to the surface. Preliminary results show evidence of removal of aerosol and soot from the atmosphere and thus their potential deposition to the surface. Altitude profiles have shown that the removal of particles appeared to be almost inexistent above the inversion layer at 200-300 m asl. Below this inversion layer the pollutant and particularly soot particles are drastically decreasing. This removal seems to be amplified in the area above the sea ice and particularly above open leads (open water cells in the sea ice). Looking in a more detailed analysis at the type of cloud and at the variation and type of air masses encountered should allow to identify characteristic cases in Arctic that could be used to constrain climate models.

Umsatz der organischen Substanz in Waldböden unter erhöhtem N-Eintrag: In situ Tracerversuche mit 13C und 15N markierter Buchenstreu

Das Projekt "Umsatz der organischen Substanz in Waldböden unter erhöhtem N-Eintrag: In situ Tracerversuche mit 13C und 15N markierter Buchenstreu" wird vom Umweltbundesamt gefördert und von Eidgenössische Forschungsanstalt für Wald, Schnee und Landschaft, Eidgenössisches Institut für Schnee- und Lawinenforschung durchgeführt. Aims The objectives are to study how increased atmospheric N deposition will affect soil organic matter turnover. We will add large amounts of double-labelled (13C and 15N) beech litter, leafs and wood-chips, to forest soil and to trace the fate of the added C and N through the soil system under ambient and experimentally increased N inputs (+50 kg NH4NO3-N ha-1y-1). Scientific Background Soils contain the largest fraction of the terrestrial carbon pools. Their role as sinks for atmospheric CO2, however, is strongly debated. One of the unknowns is the impact of the currently increased N deposition to forest ecosystems. Nitrogen is the limiting nutrient for many processes in the plant and soil system, and as the cycling of C and N are tightly coupled, increased N deposition affects also the cycling of soil organic matter (SOM). Modelling studies suggest that increased N inputs stimulate the turnover of C due to decreasing C/N ratios. In contrast, many field studies have shown that higher N inputs suppress CO2 effluxes from soils. Recent radiocarbon studies and 13C tracer experiments have indicated that N deposition retards particularly the decomposition of older and stable SOM-pools and thus, increased N inputs might lead to a sequestration of C in the long-term. The underlying mechanisms of this preservation effect, however, are not well known. Methods We will add 13C and 15N-labelled litter (leafs and wood) from a previous CO2 enrichment experiment to soils and we will follow the fate of the added C and N in the litter itself, in mineral soils and their microbial communities, in leached DOC, and in respired CO2. Expected Results The tracing of litter-derived C and N in soils will allow us (1) to identify how increased N deposition affects CO2 effluxes and DOC leaching and (2) to estimate which SOM-pools (labile litter-derived or stabile SOM) respond most sensitive to the increased N inputs. (3) To test if high N inputs in fact retard lignin degradation as hypothesized by some authors, we intend to gain insight into underlying mechanisms by tracing the fate of the labelled lignin monomers in the litter itself, soils, and in DOC and by measuring the activity of lignin degrading enzymes. (4) To elucidate if N deposition changes the microbial communities, e.g. by favouring fast growing microbes specialised on fresh substrate and suppressing slow-growing microbes relying mainly on SOM, we will analyse the 13C in phospholipid fatty acids extracted from soils and from the decomposing litter. (5) To identify how the litter-derived N becomes stabilised in soils, we will trace the 15N signal into physically separated pools of SOM with turnover rates known from their 13C signature.

Anthropogenic carbon and heat uptake by the Southern Ocean

Das Projekt "Anthropogenic carbon and heat uptake by the Southern Ocean" wird vom Umweltbundesamt gefördert und von Eidgenössische Technische Hochschule Zürich, Institut für Biogeochemie und Schadstoffdynamik durchgeführt. Heat and carbon dioxide exchange between the atmosphere and ocean is a major control on Earths climate and increasing atmospheric carbon dioxide (CO2) and concomitant global warming stimulate uptake of both heat and CO2 by the ocean. The Southern Ocean south of 30 S, occupying just over 1/4 of the surface ocean area, accounts for a disproportionate share of the vertical exchange of properties between the deep and surface waters of the ocean and between the surface ocean and the atmosphere. On average, the Southern Ocean absorbs 70Prozent of anthropogenic heat and 42Prozent of anthropogenic carbon in a new set of climate model simulations. This region thus plays a central role in determining the rate of climate change. However, the exact processes governing the magnitude and regional distribution of heat and carbon uptake remain poorly understood with models showing the largest disagreement in Southern Ocean anthropogenic air-sea heat and CO2 fluxes due to their widely divergent representation of physical circulation and atmosphere-ocean interactions. Indeed, the fraction of the simulated uptake within the Southern Ocean ranges between 30 to 160Prozent for excess heat and between 38 to 47Prozent for anthropogenic carbon. Natural unforced variability in models and observations further complicates the detection and attribution of changes. We will investigate anthropogenic ocean heat and carbon uptake with our main objectives being: (i) intercomparing ocean heat and carbon uptake in Earth System Model (ESM) simulations conducted for the Coupled Model Intercomparison Project Phase 5 (CMIP5), (ii) assessing the contribution of internal variability to model-model and model-data differences in anthropogenic heat and carbon uptake, and (iii) quantifying the contribution of differences in basic atmospheric forcing, model parameterizations, sea ice representation and model resolution to differences in heat and carbon uptake and distribution, and disagreements between models. This will be achieved through a series of process-perturbation experiments and ensemble simulations with an Earth System Model configured for transient climate change that help in attributing variations over the Southern Ocean. We will also contribute to the broader community goal in interpreting projections of IPCC AR5 coupled climate models. Ultimately, the project leads to a better understanding of Southern Ocean biogeochemical processes, thereby pinning down one of the greatest sources of uncertainty in predictions of the fate of anthropogenic carbon and of the climate.

Glass Recovering Revolution: High performance Optical Sorter for glass collection from Waste (SEEGLASS)

Das Projekt "Glass Recovering Revolution: High performance Optical Sorter for glass collection from Waste (SEEGLASS)" wird vom Umweltbundesamt gefördert und von Picvisa Machine Vision Systems SL durchgeführt. The amount of Municipal Solid Waste (MSW) in the EU28 reached 245 million tons in 2012. Nowadays, Europe directives for waste management are more restrictive each year (e.g Landfill Directive 1999/31/EC), but unfortunately, landfill disposal still represents 34% of total MSW generated. On the other hand, citizen awareness as well as the high fees operators pay for landfill disposal, have helped to greatly increase the percentage for recycling from 18% in 1995, to 42% in 2012. However, 40% of all the glass waste ends up in mixed MSW plants (which typically contain 7% of glass). Instead of being disposed of in selective-waste collection, it ends up in landfills or is composted/incinerated with the remnant waste. We have developed SEEGLASS, a high performance optical sorter based on computer vision and a pneumatic rejection system. Our aim is to solve this non-environmentally friendly problem, while also offering our end-users additional revenues with this recovered material, which is not being exploited now (49€/tn glass). In addition, extracting this glass, will allow the treatment plants to significantly reduce costs from waste disposal fees (50€/Tonne EU average and rising). Payback for customers is estimated in only 19 months. With this project we will (i) construct pre-conditioning process line, (ii) optimise our current SEEGLASS computer vision system as well as its mechanical and pneumatic design, to reach 80% glass recovery, with 99% purity, (iii) integrate both, the process line and the glass sorter solution into a demonstrator system, and (iv) validate its feasibility in-house with real MSW coming from different countries, as well as carry-out an 24/7 end-user validation. We, PICVISA, will be the first company to recover the glass fraction in refined MSW worldwide (the niche market exists worldwide) selling Turn-key installations or only SEEGLASS units, contributing to a disruptive change in the sector.

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