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SOLEIL: Solar variability and trend effects in layers and trace gasesin the upper atmosphere

Das Projekt "SOLEIL: Solar variability and trend effects in layers and trace gasesin the upper atmosphere" wird vom Umweltbundesamt gefördert und von Leibniz-Institut für Atmosphärenphysik e.V. an der Universität Rostock durchgeführt. In der wissenschaftlichen Klimadiskussion steht der Einfluss des Anstiegs anthropogener Treibhausgase auf die globale Änderung unserer Atmosphäre in den untersten Kilometern im Vordergrund. Allerdings ist die bisher eingetretene mittlere globale Temperaturerhöhung mit 0.85 K von 1880 bis 2012, dies entspricht 0.06 K pro Dekade, jedoch klein. In der Atmosphäre oberhalb von etwa 8 km kehrt sich das Vorzeichen des Treibhauseffekts um: ein Anstieg der Konzentration von infrarot-aktiven Gasen führt zu einer Abkühlung durch eine gesteigerte Emission von Strahlung in den Weltraum. Die globale Veränderung der Atmosphäre findet besonders stark in einem Höhenbereich von 50-75 km statt. Antworten auf die Fragen nach den Ursachen für diese rapiden Änderungen in der mittleren Atmosphäre können uns nur numerische Atmosphärenmodelle (z.B. LIMA) geben. Letztere zeigen, dass die Strahlungsbilanz der mittleren Atmosphäre weitgehend bestimmt wird durch die Spurengase CO2 und O3. Die multivariate Trendanalyse erlaubt nun eine Aussage über den Beitrag am Gesamttrend der einzelnen Spurengase O3 und CO2. Die Spurengase CO2 und O3 tragen jeweils 2/3 bzw. 1/3 zum Trend bei. Die größten Trends liegen im Drucksystem mit 1.3 K/Dekade bei ca. 60 km, während auf geometrischen Höhen der Kontraktionseffekt der Atmosphäre die maximalen Trends auf bis zu 1.8 K/Dekade bei 70 km verstärkt. In den Höhen 80-90 km sind die Trendwerte am kleinsten und können sogar das Vorzeichen wechseln. Dieses Verhalten ist bedingt durch die sehr niedrigen Absoluttemperaturen in 80-90 km Höhe, die sehr empfindlich auf Variationen in den Strahlungsflüssen aus der Stratopausenregion reagieren. Weiterhin konnte in 'SOLEIL' gezeigt werden, dass Temperaturtrends zeitlich variabel sind. So zeigen im Teilzeitraum 1980-1996 die Temperaturen ihren stärksten Abfall aufgrund der Ozonabnahme: die Temperaturtrends können Werte bis zu 4 K pro Dekade erreichen. Im Zeitraum 1995-2009 sind die Durchschnittstemperaturen nahezu unverändert, weil sich hier das stratosphärische Ozon wieder aufbaut ('ozone recovery'). Diese Phasen starker und schwacher Abkühlung zwischen 1961 bis 2008 sind konsistent mit abgeleiteten Temperaturtrends aus französischen Lidarbeobachtungen und Phasenhöhenmessungen am Institut für Atmosphärenphysik (IAP) Kühlungsborn. Der Höhenbereich 80-90 km ist auch die Region, in der Eiswolken seit mehr als 100 Jahren beobachtet werden. Diese Eiswolken (NLC/PMC) existieren in der Sommermesopausenregion polwärts ab 50°N und können sich nur unter sehr kalten Temperaturen unterhalb von etwa 150 K ausbilden. Obwohl der Wasserdampfgehalt in der Mesopausenregion mit 1-7 ppmv sehr gering ausfällt, ist diese Feuchtekonzentration ausreichend für die Bildung von Eisteilchen. Die Nukleation und das Wachstum dieser Eispartikel reagiert sehr empfindlich auf Änderungen der Temperatur und des Wasserdampfes. Aus diesem Grund werden NLC/PMC auf ihre Rolle als potentieller Indikator für Klimaänderungen der globalen Atmosph

C3: Market inclusion of ecosystem services: A viable option to achieve sustainable land use in the tropics?

Das Projekt "C3: Market inclusion of ecosystem services: A viable option to achieve sustainable land use in the tropics?" wird vom Umweltbundesamt gefördert und von Technische Universität München, Wissenschaftszentrum Weihenstephan für Ernährung, Landnutzung und Umwelt, Fachgebiet für Waldinventur und nachhaltige Nutzung durchgeführt. The concept of ecosystem services (ES) links ecosystem functioning and human wel-fare to achieve sustainable land use. However, the success of this concept will critically depend on sources to finance the provision of ES (possibly mobilized by means of markets for ES), on credibility of ES values and on willingness of ES providers to ac-cept financial compensation. Our proposal addresses these aspects: The first part investigates how the land use in Ecuador would change if ES were actually acknowl-edged as economic values. We will use and develop a risk sensitive economic modeling approach to integrate the uncertainty of expected economic values for ES. The aim is to explore how the uncertainty of ES values would affect investments into specific ecosystem types and the connected conversion processes from tropical forest lands to other land use types and vice versa. The second proposal part investigates the willing-ness to accept financial compensation for providing ES. In this part we adapt a risk-sensitive bioeconomic farm model that combines various productive but sustainable land management options to real farm situations. The farm level modeling builds upon the effects of risk compensation from diversified land use by means of a land use port-folio approach. It will be used to derive acceptable individual and thus effective conser-vation payments.

Upwelling in the Atlantic sector of the Southern Ocean

Das Projekt "Upwelling in the Atlantic sector of the Southern Ocean" wird vom Umweltbundesamt gefördert und von Universität Bremen, Institut für Umweltphysik, Abteilung Ozeanographie durchgeführt. Upwelling is an important process in setting the characteristic of the mixed layer. Upwelling also provides a pathway for gases, nutrients, and other compounds from the ocean's interior into the mixed layer and ultimately into the atmosphere. Since the upwelling velocities are small, they cannot be measured directly. Recently, Rhein et al. (2010) exploited the helium isotope disequilibria found in the equatorial eastern Atlantic to infer upwelling speeds, upwelling rates, and vertical heat fluxes between the mixed layer and the ocean's interior. The disequilibrium in the mixed layer is caused by upwelling of 3He-enriched water from the interior. The surplus 3He is introduced into the deep ocean by hydrothermal activities.A first survey of historical Helium isotope data in the Antarctic Circumpolar Current (ACC) and the Weddell Sea showed, that the mixed layer is also enriched with 3He, which in summer months is supplied by upwelling of water from below the mixed layer. Although the first estimates of upwelling velocities from the historical data set look promising, the present Helium data lack a sufficient resolution in the upper 200-300m to determine the horizontal and vertical He gradients, necessary for the compilation of the upwelling velocity and of the contribution of diapycnal mixing. Here we propose to take the historical He data, and a new dedicated He data sets to be taken in November 2010 - February 2011 during the POLARSTERN cruise ANT 27/2 and January- February 2012 during POLARSTERN cruise ANT28/3 to calculate upwelling speeds and -rates in the Weddell Sea and the ACC, as well as heat fluxes between the interior and the mixed layer.This proposal is part of the Cluster ' Eddies and Upwelling: Major Factors in the Carbon Budget ofthe Southern Ocean'

Biomass Fuell Cell Utility System (BIOCELLUS)

Das Projekt "Biomass Fuell Cell Utility System (BIOCELLUS)" wird vom Umweltbundesamt gefördert und von Technische Universität München, TUM School of Engineering and Design, Fakultät für Maschinenwesen, Lehrstuhl für Energiesysteme durchgeführt. Objective: Energy from Biomass needs highly efficient small-scale energy systems in order to achieve cost effective solutions for decentralized generation especially in Mediterranean and Southern areas, and for applications without adequate heat consumer. Thus fuel cells are an attractive option for decentralized generation from biomass and agricultural residues but they have to meet at least two outstanding challenges: 1. Fuel cell materials and the gas cleaning technologies have to treat high dust loads of the fuel gas and pollutants like tars, alkalines and heavy metals. 2. The system integration has to allow efficiencies of at least 40-50 percent even within a power range of few tens or hundreds of kW. This proposal addresses in particular these two aims. Hence the first part of the project will focus on the investigation of the impact of these pollutants on degradation and performance characteristics of SOFC fuel cells in order to specify the requirements for appropriate gas cleaning system (WP 1-2). These tests will be performed at six existing gasification sites, which represent the most common and applicable gasification technologies. WP 3 will finally test and demonstrate the selected gas cleaning technologies in order to verify the specifications obtained from the gasification tests. The results will be used for the development, installation and testing of an innovative SOFC - Gasification concept, which will especially match the particular requirements of fuel cell systems for the conversion of biomass feedstock. The innovative concept comprises to heat an allothermal gasifier with the exhaust heat of the fuel cell by means of liquid metal heat pipes. Internal cooling of the stack and the recirculation of waste heat increases the system efficiency significantly. This so-called TopCycle concept promises electrical efficiencies of above 50 percent even for small-scale systems without any combined processes.

Mini-DOAS Messungen während der HALO Southtrac Mission im Herbst 2019

Das Projekt "Mini-DOAS Messungen während der HALO Southtrac Mission im Herbst 2019" wird vom Umweltbundesamt gefördert und von Universität Heidelberg, Institut für Umweltphysik durchgeführt. Mit dem Antrag soll die Teilnahme des mini-DOAS Instrumentes an der Southtrac Kampagne im Herbst 2019, sowie die Auswertung, Interpretation und Veröffentlichung der dabei gemessenen Daten beantragt werden. Das mini-DOAS Instrument ist ein passives Fernerkundungsinstrument mit dem gleichzeitig in Nadir- und Limb-Richtung Himmelsstreulicht im UV/vis/NIR von Bord des Forschungsflugzeuges HALO gemessen und spektral analysiert wird. Mit den Messungen können mit Hilfe der Differentiellen Optischen Absorptions Spektroskopie (DOAS) die Konzentrationen wichtiger Spurenstoffe auf Flughöhe, sowie Vertikalprofile und vertikale Säulen bestimmt werden, wobei einige der gemessenen Spurenstoffe mit anderen Messmethoden nicht (BrO, OClO, IO, C2H2O2, und C3H4O2) oder nur schwer (NO2, HONO, und CH2O) nachweisbar sind. Die Messungen im Nadir und Limb erlauben auch alle 3 Phasen des atmosphärischen H2O (u.a. den Wasser- und Eiswasserpfad), Eigenschaften des atmosphärischen Strahlungstransportes (u.a. relative Radianzen, Photonenweglängen, ...), sowie einige mikrophysikalische Eigenschaften von Aerosole und Wolkenteilchen zu bestimmen. Mit den Messungen des mini-DOAS Instrumentes sollen im Rahmen der Southtrac Kampagne drei spezielle wissenschaftlichen Ziele verfolgt werden (CHEM-1_Q1, CHEM-1_Q2 und CHEM-2_Q1), die im Einklang mit dem Kampagnenantrag stehen. Insbesondere (a) komplettieren unsere hochgenauen Messungen von BrO (und IO) das Budget der ozonschädlichen Brom- und Iodverbindungen (CHEM-1_Q1), und (b) helfen die Messungen von BrO und OClO den Ozonverlust in der oberen Troposphäre unteren Stratosphäre einzugrenzen (CHEM-1_Q2). Weiterhin dienen (c) die Messungen von NO2, HONO, aber insbesondere auch von CH2O und C2H2O2 die Abluft aus der Biomassenverbrennung nachzuweisen (CHEM-2_Q1).

Storage of hydrogen in hydrides

Das Projekt "Storage of hydrogen in hydrides" wird vom Umweltbundesamt gefördert und von Weierstraß-Institut für Angewandte Analysis und Stochastik durchgeführt. Hydrogen is the ideal synthetic fuel to convert chemical energy into electrical energy or into motive power because it is light weight, highly abundant and its oxidation product is vapor of water. Thus its usage helps to reduce the greenhouse gases and it conserves fossile resources. There is even a clean way to produce hydrogen by electrolysis of water by means of photo voltaics (SvW06, VSM05, PMM05). There are various possibilities to store the hydrogen for later use: Liquid and gaseous hydrogen can be stored in a pressure vessel, hydrogen can be adsorped on large surface areas of solids, and finally crystal lattices of metals or other compounds can be used as the storage system, where hydrogen is dissolved either on interstitial or on regular lattice sites by substitution (SvW06, San99). The latter process and its reversal is called hydriding respectively dehydriding. The subject of this proposal is the modeling and simulation of that process. The main problem of a rechargeable lithium-ion battery is likewise a storage problem, because in a rechargeable battery, both the anode and cathode do not directly take part in the electrochemical process that converts chemical energy into electrical energy, rather they act as host systems for the electron spending element, which is here lithium (Li). During the last month the applicant developed and exploited a mathematical model that is capable to capture the storage problem of an iron phosphate (FePO4) cathode, where the Li atoms are stored on interstitial lattice sites (DGJ07).

A census of viruses through the drinking water cycle

Das Projekt "A census of viruses through the drinking water cycle" wird vom Umweltbundesamt gefördert und von Charité - Universitätsmedizin Berlin, Campus Charité Mitte (CCM), Institut für Virologie durchgeführt. Waterbome viruses have a high but so far underestimated public health significance. In water monitoring and surveillance regulations, virus detection is until now not mandatory. This is reflected in the methodological repertoire available. To date, methods for detecting the various types of viruses in different types of waters (waste water, surface water, groundwater, drinking water) are insufficiently sensitive. Some of the most important waterborne viruses like noroviruses can only be detected by PCR methods. In the case of waterborne virus outbreaks, underlying circumstances and causes frequently cannot be clarified in the absence of reliable detection methodology. The same would apply to acts of biological crime or terrorism. It is thus of utmost importance to further develop methods for sensitive and reliable virus detection in different types of waters which are technically easy to accomplish in a short time, provide a sufficient concentration of a large range of viruses in a mall volume, have a high virus recovery rate, will not be too costly, and will deliver reproducible results. In this proposal methods for concentrating large volumes of water by which a large spectrum of viruses can be simultaneously detected in water samples will be developed in cooperation with individual project partners. After successful development and testing in the lab, the methods will be evaluated for its use in different waters and water treatment steps for quantitative and qualitative virus analysis.

Origin and fate of dissolved organic matter in the subsoil

Das Projekt "Origin and fate of dissolved organic matter in the subsoil" wird vom Umweltbundesamt gefördert und von Leibniz Universität Hannover, Institut für Bodenkunde durchgeführt. Dissolved organic matter (DOM) is one major source of subsoil organic matter (OM). P5 aims at quantifying the impact of DOM input, transport, and transformation to the OC storage in the subsoil environment. The central hypotheses of this proposal are that in matric soil the increasing 14C age of organic carbon (OC) with soil depth is due to a cascade effect, thus, leading to old OC in young subsoil, whereas within preferential flowpaths sorptive stabilization is weak, and young and bioa-vailable DOM is translocated to the subsoil at high quantities. These hypotheses will be tested by a combination of DOC flux measurements with the comparative analysis of the composition and the turnover of DOM and mineral-associated OM. The work programme utilizes a DOM monitoring at the Grinderwald subsoil observatory, supplemented by defined experiments under field and labora-tory conditions, and laboratory DOM leaching experiments on soils of regional variability. A central aspect of the experiments is the link of a 13C-leaf litter labelling experiment to the 14C age of DOM and OM. With that P5 contributes to the grand goal of the research unit and addresses the general hypotheses that subsoil OM largely consists of displaced and old OM from overlying horizons, the sorption capacity of DOM and the pool size of mineral-associated OM are controlled by interaction with minerals, and that preferential flowpaths represent 'hot spots' of high substrate availability.

Plant induced weathering of minerals in the subsoil - release of 'non-exchangeable' potassium from 2:1 layer minerals (TransMinK)

Das Projekt "Plant induced weathering of minerals in the subsoil - release of 'non-exchangeable' potassium from 2:1 layer minerals (TransMinK)" wird vom Umweltbundesamt gefördert und von Universität Halle-Wittenberg, Institut für Agrar- und Ernährungswissenschaften, Professur für Bodenkunde und Bodenschutz durchgeführt. The proposal addresses the potential of subsoil to contribute to K nutrition of crops. More specifically we will address the processes controlling release of K from interlayer of 2:1 clay minerals as this is expected to be the dominant K fraction in the subsoil. While it has been shown in the past that this so called 'non-exchangeable' K can be released due to root activity, there are controversial results concerning the role of soil solution K concentration in the rhizosphere required to trigger the process. Likewise little information is available about the concentration dynamics of other cations (NH4, Ca) in the rhizosphere and their impact on K release and vermiculitization supposed to be associated with this process. Model studies with substrate from the central field trial will be conducted in compartment systems equipped with micro suction cups. The measurement of dynamic changes of soil solution composition with increasing distance from the root surface will be combined with investigations of changes in mineralogy by XRD, TEM and SEM-EDX. Changes of mineralogy as a result of plant induced K release from interlayer will also be studied on bulk soil and rhizosphere samples collected within the central field and the central microcosm experiment and with mineral bags exposed in the field during a cropping cycle. Finally, X-ray CT will be used to access changes in soil texture, i.e. clay distribution around roots and the temporal spread of roots in biopores which is a prerequisite for K uptake from such structures.

The fate of phosphorus in forest and treeline ecosystems in Ecuador

Das Projekt "The fate of phosphorus in forest and treeline ecosystems in Ecuador" wird vom Umweltbundesamt gefördert und von Universität Tübingen, Fachbereich Geowissenschaften, Forschungsbereich Geographie durchgeführt. Even remote areas such as tropical montane forests suffer from continuously high atmospheric nitrogen (N) and phosphorus (P) deposition. In studies on ecosystem responses to atmospheric nutrient deposition, P cycling has played an underrated role compared to N, although P is thought to limit organism growth in main parts of the Tropics. Furthermore, the responses of tropical montane forests to atmospheric nutrient deposition might depend on the predicted climate change i.e., shifts in temperature and precipitation. Altitudinal gradients represent an ideal means to study environmental changes in tropical montane forests in southern Ecuador, because climate scenarios and unpublished trends in longer-term climate data predict increasing temperatures and decreased moisture which parallels the altitudinal gradient from 4000 m to 1000 m asl.Previous experiments, including the NUMEX experiment in Ecuador, showed that the main proportion of P added to forests to simulate atmospheric deposition was retained in soil. While total P pools in soil respond slowly to low P addition rates, the biological and geochemical processes underlying retention in the organic layer or in soil are expected to react faster. Our overarching objective is to assess the fate of fertilized P in the organic layer and in mineral soil and to elucidate the processes involved in P cycling in soil (immobilization and release rates by microorganisms, sorption/desorption, precipitation/dissolution) along the NUMEX-X altitudinal gradient (1000, 2000, 3000, 4000m; the latter including a Polylepis and a Páramo ecosystem). We will assess P fractions in soil and use a combination of 33P tracer studies and incubation experiments to disentangle biological and geochemical processes controlling P retention. The mechanistic understanding gathered by this proposal is crucial for predictions of ecosystems responses to the continuously high atmospheric N (and P) deposition, because single mechanisms might respond differently (and oppositionally) in the long run. Because the processes involved in P cycling are expected to respond faster to environmental changes than e.g., P pools in soil, these different responses are an essential basis to evaluate effects of environmental change and finally, to develop early-warning ecosystem indicators for environmental change.

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