64 resultados para MessyGA Messy


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The chapters in this book were originally published in the The International Spectator, volume 47, issue 1 (February 2012).

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Luchar por la inserción laboral de los jóvenes con discapacidad intelectual en el mercado laboral competitivo, ofreciéndoles las ayudas que necesitan en función de sus particularidades y de las necesidades del contexto donde se encuentren. Promover políticas activas de empleo destacándose entre sus objetivos crear y mantener fuentes de empleo y fomentar la inserción laboral. Se ha estructurado en tres capítulos, dos de corte teórico y uno de corte empírico. En el último se realiza un análisis de los instrumentos de evaluación destinados a la valoración de habilidades sociales y de afrontamiento, y además se utiliza el Perfil de Personalidad Laboral - PPL (adaptado de Bolton y Roessler) y el tests de Messy, para profesionales y alumnos. Ambos tests se utilizan a lo largo del trabajo en dos momentos: pre-test y post-test, con la finalidad de analizar la variabilidad-estabilidad de habilidades sociales y de afrontamiento, tras la aplicación del programa de intervención -Desarrollo Vocacional-. Los jóvenes con discapacidad intelectual al pretender insertarse al mundo laboral y especialmente al empleo normalizado, lo encuentran difícil. A pesar de las mejoras que se advierten en los últimos estudios realizados dicha realidad continúa reflejando una falta de equiparación de derechos y de oportunidades. Entre otros factores, se constata una brecha en materia laboral entre las personas con discapacidad respecto al conjunto de la población, duplicándose la tasa de desempleo de las personas con discapacidad.

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Desarrollar estrategias para intervenir sistem??ticamente en la conducta interpersonal de los ni??os y ni??as. Desarrollar y adoptar instrumentos de evaluaci??n de la conducta interpersonal enla edad escolar. Evaluar el Programa de Habilidades de Interacci??n Social (PHIS). La muestra est?? compuesta por 48 ni??os de 4 a 12 a??os, de preescolar a quinto de EGB. La poblaci??n de la que se extrae la muestra est?? compuesta por 781 alumnos de 35 aulas de cuatro centros de EGB de la ciudad de Valladolid. Se utiliza un dise??o experimental de grupo de control pretset-postest. Se contemplan tres grupos: dos grupos experimentales (que se diferencian entre s?? por la intensidad del tratamiento) y un grupo control. Las variables que se contemplan son: el Programa de Habilidades de Interacci??n Social (PHIS) y el modelo de intervenci??n asociado (variable independiente), la competencia social y habilidades sociales (variables dependientes referidas a los sujetos). Se aplica una estrategia de evaluaci??n multimodal utilizando un Paquete de Evaluaci??n Comprensiva que contempla distintas fuentes de informaci??n y evaluaci??n (padres, profesores, observadores, los compa??eros y el propio sujeto). El paquete de evaluaci??n consta de un total de once instrumentos de evaluaci??n. La mayor??a de estos han sido elaborados y construidos ad hoc o adaptados y traducidos para la presente investigaci??n: el procedimiento sociom??trico para profesores (PS-P), el procedimiento sociom??trico para ni??os (PS-N), el ACCEPTS (A Curriculum for childrens Effective Peer and Teacher Skills) Placement Test, el Matson Evaluation of Social Skills with Youngsters (MESSY), cuestionario de habilidades de interacci??n social (CHIS), c??digo de observaci??n de la interacci??n social (COIS), bater??a de habilidades interpersonales (BHIP), cuestionario para padres, cuestionario de implementaci??n y satisfacci??n para profesores (CUI-PR), cuestionario de implementaci??n y satisfacci??n para padres (CUI-PA) y cuestionarios de seguimiento. El tratamiento estad??stico de los datos se realiza con el paquete SPSS. Se utilizan las pruebas de contraste: an??lisis de varianza (para datos que permiten un tratamiento param??trico) y las pruebas no param??tricas de Kruskal Wallis y la U de Mann Whitney. Tambi??n se utiliza el an??lisis de varianza de medidas repetidas. Se evidencian diferencias significativas en favor de los grupos experimentales en la mayor??a de las variables dependientes consideradas. Asimismo, el PHIS y el modelo de intervenci??n asociado es efectivo para el tratamiento de profesores y padres ya que incrementa su competencia tanto profesional como parental en el ??rea interpesonal. Adem??s, se demuestra adecuada validez social de la intervenci??n, aceptable mantenimiento y cierto grado de generalizaci??n de los efectos del tratamiento. Los entrenamientos en habilidades sociales son estrategias de intervenci??n y ense??anza del comportamiento interpersonal que se muestran efectivos para la ense??anza de las habilidades de interacci??n social en la infancia. Por ello es necesario incluir programas de ense??anza de las habilidades sociales dentro de los curriculum educativos habituales de los centros de EGB.

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The biggest challenge in conservation biology is breaking down the gap between research and practical management. A major obstacle is the fact that many researchers are unwilling to tackle projects likely to produce sparse or messy data because the results would be difficult to publish in refereed journals. The obvious solution to sparse data is to build up results from multiple studies. Consequently, we suggest that there needs to be greater emphasis in conservation biology on publishing papers that can be built on by subsequent research rather than on papers that produce clear results individually. This building approach requires: (1) a stronger theoretical framework, in which researchers attempt to anticipate models that will be relevant in future studies and incorporate expected differences among studies into those models; (2) use of modern methods for model selection and multi-model inference, and publication of parameter estimates under a range of plausible models; (3) explicit incorporation of prior information into each case study; and (4) planning management treatments in an adaptive framework that considers treatments applied in other studies. We encourage journals to publish papers that promote this building approach rather than expecting papers to conform to traditional standards of rigor as stand-alone papers, and believe that this shift in publishing philosophy would better encourage researchers to tackle the most urgent conservation problems.

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This paper explores the process of learning an embodied knowledge using the work of Dreyfus and Deleuze. Although geographers have begun to acknowledge the role of embodied knowledges in social life, there have been few in-depth case studies of how these skills are learned. This paper offers a case study of Thai Yoga massage (TYM), a ‘complementary and alternative therapy’ which is growing in popularity in the United Kingdom. Having outlined the case study, the paper explores the cultural geographies of the formalisation, documentation and contestation of the set of techniques that have come to cohere in the UK as TYM. The paper then interrogates the messy corporeal geographies of learning a skill, and briefly considers how more advanced practitioners experience their skilled practice.

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This article reflects on the introduction of ‘matrix management’ arrangements for an Educational Psychology Service (EPS) within a Children’s Service Directorate of a Local Authority (LA). It seeks to demonstrate critical self-awareness, consider relevant literature with a view to bringing insights to processes and outcomes, and offers recommendations regarding the use of matrix management. The report arises from an East Midland’s LA initiative: ALICSE − Advanced Leadership in an Integrated Children’s Service Environment. Through a literature review and personal reflection, the authors consider the following: possible tensions within the development of matrix management arrangements; whether matrix management is a prerequisite within complex organizational systems; and whether competing professional cultures may contribute barriers to creating complementary and collegiate working. The authors briefly consider some research paradigms, notably ethnographic approaches, soft systems methodology, activity theory and appreciative inquiry. These provide an analytic framework for the project and inform this iterative process of collaborative inquiry. Whilst these models help illuminate otherwise hidden processes, none have been implemented following full research methodologies, reflecting the messy reality of local authority working within dynamic organizational structures and shrinking budgets. Nevertheless, this article offers an honest reflection of organizational change within a children’s services environment.

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This book follows a revolutionary trend popular among young activists and would-be radicals after 1917, the formation of collective units of cohabitation and association known as 'urban communes'. In these spaces, activists tried to live what they understood as the 'socialist lifestyle', self-consciously putting Marxist and Bolshevik theories into practice. By telling the story of the urban communes, this book reveals how grand revolutionary ideals, such as collectivism, equality, proletarian ethics, and modern practice, were experienced, understood, and appropriated on a human level. This enables us to better understand the messy realities of the early Soviet state, showing how ideological beliefs and revolutionary contingencies actually came into being during this time.

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Inspired by the commercial desires of global brands and retailers to access the lucrative green consumer market, carbon is increasingly being counted and made knowable at the mundane sites of everyday production and consumption, from the carbon footprint of a plastic kitchen fork to that of an online bank account. Despite the challenges of counting and making commensurable the global warming impact of a myriad of biophysical and societal activities, this desire to communicate a product or service's carbon footprint has sparked complicated carbon calculative practices and enrolled actors at literally every node of multi-scaled and vastly complex global supply chains. Against this landscape, this paper critically analyzes the counting practices that create the ‘e’ in ‘CO2e’. It is shown that, central to these practices are a series of tools, models and databases which, in building upon previous work (Eden, 2012 and Star and Griesemer, 1989) we conceptualize here as ‘boundary objects’. By enrolling everyday actors from farmers to consumers, these objects abstract and stabilize greenhouse gas emissions from their messy material and social contexts into units of CO2e which can then be translated along a product's supply chain, thereby establishing a new currency of ‘everyday supply chain carbon’. However, in making all greenhouse gas-related practices commensurable and in enrolling and stabilizing the transfer of information between multiple actors these objects oversee a process of simplification reliant upon, and subject to, a multiplicity of approximations, assumptions, errors, discrepancies and/or omissions. Further the outcomes of these tools are subject to the politicized and commercial agendas of the worlds they attempt to link, with each boundary actor inscribing different meanings to a product's carbon footprint in accordance with their specific subjectivities, commercial desires and epistemic framings. It is therefore shown that how a boundary object transforms greenhouse gas emissions into units of CO2e, is the outcome of distinct ideologies regarding ‘what’ a product's carbon footprint is and how it should be made legible. These politicized decisions, in turn, inform specific reduction activities and ultimately advance distinct, specific and increasingly durable transition pathways to a low carbon society.

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Drawing upon Brazilian experience, this research explores some of the key issues to be addressed in using e-government technical cooperation designed to enhance service provision of Patent Offices in developing countries. While the development of software applications is often seen merely as a technical engineering exercise, localization and adaptation are context bounded matters that are characterized by many entanglements of human and non-humans. In this work, technical, legal and policy implications of technical cooperation are also discussed in a complex and dynamic implementation environment characterized by the influence of powerful hidden agendas associated with the arena of intellectual property (IP), which are shaped by recent technological, economic and social developments in our current knowledge-based economy. This research employs two different theoretical lenses to examine the same case, which consists of transfer of a Patent Management System (PMS) from the European Patent Office (EPO) to the Brazilian Patent Office that is locally named ‘Instituto Nacional da Propriedade Industrial’ (INPI). Fundamentally, we have opted for a multi-paper thesis comprising an introduction, three scientific articles and a concluding chapter that discusses and compares the insights obtained from each article. The first article is dedicated to present an extensive literature review on e-government and technology transfer. This review allowed the proposition on an integrative meta-model of e-government technology transfer, which is named E-government Transfer Model (ETM). Subsequently, in the second article, we present Actor-Network Theory (ANT) as a framework for understanding the processes of transferring e-government technologies from Patent Offices in developed countries to Patent Offices in developing countries. Overall, ANT is seen as having a potentially wide area of application and being a promising theoretical vehicle in IS research to carry out a social analysis of messy and heterogeneous processes that drive technical change. Drawing particularly on the works of Bruno Latour, Michel Callon and John Law, this work applies this theory to a longitudinal study of the management information systems supporting the Brazilian Patent Office restructuration plan that involved the implementation of a European Patent Management System in Brazil. Based upon the ANT elements, we follow the actors to identify and understand patterns of group formation associated with the technical cooperation between the Brazilian Patent Office (INPI) and the European Patent Office (EPO). Therefore, this research explores the intricate relationships and interactions between human and non-human actors in their attempts to construct various network alliances, thereby demonstrating that technologies embodies compromise. Finally, the third article applies ETM model as a heuristic frame to examine the same case previously studied from an ANT perspective. We have found evidence that ETM has strong heuristic qualities that can guide practitioners who are engaged in the transfer of e-government systems from developed to developing countries. The successful implementation of e-government projects in developing countries is important to stimulate economic growth and, as a result, we need to understand the processes through which such projects are being implemented and succeed. Here, we attempt to improve understanding on the development and stabilization of a complex social-technical system in the arena of intellectual property. Our preliminary findings suggest that e-government technology transfer is an inherently political process and that successful outcomes require continuous incremental actions and improvisations to address the ongoing issues as they emerge.

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Biogenic aerosols are relevant for the Earth system, climate, and public health on local, regional, and global scales. Up to now, however, little is known about the diversity and biogeography of airborne microorganisms. We present the first DNA-based analysis of airborne fungi on global scales, showing pronounced geographic patterns and boundaries. In particular we find that the ratio of species richness between Basidiomycota and Ascomycota is much higher in continental air than in marine air. This may be an important difference between the 'blue ocean' and 'green ocean' regimes in the formation of clouds and precipitation, for which fungal spores can act as nuclei. Our findings also suggest that air flow patterns and the global atmospheric circulation are important for the understanding of global changes in biodiversity.

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A polar stratospheric cloud submodel has been developed and incorporated in a general circulation model including atmospheric chemistry (ECHAM5/MESSy). The formation and sedimentation of polar stratospheric cloud (PSC) particles can thus be simulated as well as heterogeneous chemical reactions that take place on the PSC particles. For solid PSC particle sedimentation, the need for a tailor-made algorithm has been elucidated. A sedimentation scheme based on first order approximations of vertical mixing ratio profiles has been developed. It produces relatively little numerical diffusion and can deal well with divergent or convergent sedimentation velocity fields. For the determination of solid PSC particle sizes, an efficient algorithm has been adapted. It assumes a monodisperse radii distribution and thermodynamic equilibrium between the gas phase and the solid particle phase. This scheme, though relatively simple, is shown to produce particle number densities and radii within the observed range. The combined effects of the representations of sedimentation and solid PSC particles on vertical H2O and HNO3 redistribution are investigated in a series of tests. The formation of solid PSC particles, especially of those consisting of nitric acid trihydrate, has been discussed extensively in recent years. Three particle formation schemes in accordance with the most widely used approaches have been identified and implemented. For the evaluation of PSC occurrence a new data set with unprecedented spatial and temporal coverage was available. A quantitative method for the comparison of simulation results and observations is developed and applied. It reveals that the relative PSC sighting frequency can be reproduced well with the PSC submodel whereas the detailed modelling of PSC events is beyond the scope of coarse global scale models. In addition to the development and evaluation of new PSC submodel components, parts of existing simulation programs have been improved, e.g. a method for the assimilation of meteorological analysis data in the general circulation model, the liquid PSC particle composition scheme, and the calculation of heterogeneous reaction rate coefficients. The interplay of these model components is demonstrated in a simulation of stratospheric chemistry with the coupled general circulation model. Tests against recent satellite data show that the model successfully reproduces the Antarctic ozone hole.

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Ein neu entwickeltes globales Atmosphärenchemie- und Zirkulationsmodell (ECHAM5/MESSy1) wurde verwendet um die Chemie und den Transport von Ozonvorläufersubstanzen zu untersuchen, mit dem Schwerpunkt auf Nichtmethankohlenwasserstoffen. Zu diesem Zweck wurde das Modell durch den Vergleich der Ergebnisse mit Messungen verschiedenen Ursprungs umfangreich evaluiert. Die Analyse zeigt, daß das Modell die Verteilung von Ozon realistisch vorhersagt, und zwar sowohl die Menge als auch den Jahresgang. An der Tropopause gibt das Modell den Austausch zwischen Stratosphäre und Troposphäre ohne vorgeschriebene Flüsse oder Konzentrationen richtig wieder. Das Modell simuliert die Ozonvorläufersubstanzen mit verschiedener Qualität im Vergleich zu den Messungen. Obwohl die Alkane vom Modell gut wiedergeben werden, ergibt sich einige Abweichungen für die Alkene. Von den oxidierten Substanzen wird Formaldehyd (HCHO) richtig wiedergegeben, während die Korrelationen zwischen Beobachtungen und Modellergebnissen für Methanol (CH3OH) und Aceton (CH3COCH3) weitaus schlechter ausfallen. Um die Qualität des Modells im Bezug auf oxidierte Substanzen zu verbessern, wurden einige Sensitivitätsstudien durchgeführt. Diese Substanzen werden durch Emissionen/Deposition von/in den Ozean beeinflußt, und die Kenntnis über den Gasaustausch mit dem Ozean ist mit großen Unsicherheiten behaftet. Um die Ergebnisse des Modells ECHAM5/MESSy1 zu verbessern wurde das neue Submodell AIRSEA entwickelt und in die MESSy-Struktur integriert. Dieses Submodell berücksichtigt den Gasaustausch zwischen Ozean und Atmosphäre einschließlich der oxidierten Substanzen. AIRSEA, welches Informationen über die Flüssigphasenkonzentration des Gases im Oberflächenwasser des Ozeans benötigt wurde ausgiebig getestet. Die Anwendung des neuen Submodells verbessert geringfügig die Modellergebnisse für Aceton und Methanol, obwohl die Verwendung einer vorgeschriebenen Flüssigphasenkonzentration stark den Erfolg der Methode einschränkt, da Meßergebnisse nicht in ausreichendem Maße zu Verfügung stehen. Diese Arbeit vermittelt neue Einsichten über organische Substanzen. Sie stellt die Wichtigkeit der Kopplung zwischen Ozean und Atmosphäre für die Budgets vieler Gase heraus.

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Mineral dust is an important component of the Earth's climate system and provides essential nutrientsrnto oceans and rain forests. During atmospheric transport, dust particles directly and indirectly influencernweather and climate. The strength of dust sources and characteristics of the transport, in turn, mightrnbe subject to climatic changes. Earth system models help for a better understanding of these complexrnmechanisms.rnrnThis thesis applies the global climate model ECHAM5/MESSy Atmospheric Chemistry (EMAC) for simulationsrnof the mineral dust cycle under different climatic conditions. The prerequisite for suitable modelrnresults is the determination of the model setup reproducing the most realistic dust cycle in the recentrnclimate. Simulations with this setup are used to gain new insights into properties of the transatlanticrndust transport from Africa to the Americas and adaptations of the model's climate forcing factors allowrnfor investigations of the impact of climatic changes on the dust cycle.rnrnIn the first part, the most appropriate model setup is determined through a number of sensitivity experiments.rnIt uses the dust emission parametrisation from Tegen et al. 2002 and a spectral resolutionrnof T85, corresponding to a horizontal grid spacing of about 155 km. Coarser resolutions are not able tornaccurately reproduce emissions from important source regions such as the Bodele Depression in Chad orrnthe Taklamakan Desert in Central Asia. Furthermore, the representation of ageing and wet deposition ofrndust particles in the model requires a basic sulphur chemical mechanism. This setup is recommended forrnfuture simulations with EMAC focusing on mineral dust.rnrnOne major branch of the global dust cycle is the long-range transport from the world's largest dustrnsource, the Sahara, across the Atlantic Ocean. Seasonal variations of the main transport pathways to thernAmazon Basin in boreal winter and to the Caribbean during summer are well known and understood,rnand corroborated in this thesis. Both Eulerian and Lagrangian methods give estimates on the typicalrntransport times from the source regions to the deposition on the order of nine to ten days. Previously, arnhuge proportion of the dust transported across the Atlantic Ocean has been attributed to emissions fromrnthe Bodele Depression. However, the contribution of this hot spot to the total transport is very low inrnthe present results, although the overall emissions from this region are comparable. Both model resultsrnand data sets analysed earlier, such as satellite products, involve uncertainties and this controversy aboutrndust transport from the Bodele Depression calls for future investigations and clarification.rnrnAforementioned characteristics of the transatlantic dust transport just slightly change in simulationsrnrepresenting climatic conditions of the Little Ice Age in the middle of the last millennium with meanrnnear-surface cooling of 0.5 to 1 K. However, intensification of the West African summer monsoon duringrnthe Little Ice Age is associated with higher dust emissions from North African source regions and wetterrnconditions in the Sahel. Furthermore, the Indian Monsoon and dust emissions from the Arabian Peninsula,rnwhich are affected by this circulation, are intensified during the Little Ice Age, whereas the annual globalrndust budget is similar in both climate epochs. Simulated dust emission fluxes are particularly influencedrnby the surface parameters. Modifications of the model do not affect those in this thesis, to be able tornascribe all differences in the results to changed forcing factors, such as greenhouse gas concentrations.rnDue to meagre comparison data sets, the verification of results presented here is problematic. Deeperrnknowledge about the dust cycle during the Little Ice Age can be obtained by future simulations, based onrnthis work, and additionally using improved reconstructions of surface parameters. Better evaluation ofrnsuch simulations would be possible by refining the temporal resolution of reconstructed dust depositionrnfluxes from existing ice and marine sediment cores.

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Stable isotope composition of atmospheric carbon monoxide: A modelling study.rnrnThis study aims at an improved understanding of the stable carbon and oxygen isotope composition of the carbon monoxide (CO) in the global atmosphere by means of numerical simulations. At first, a new kinetic chemistry tagging technique for the most complete parameterisation of isotope effects has been introduced into the Modular Earth Submodel System (MESSy) framework. Incorporated into the ECHAM/MESSy Atmospheric Chemistry (EMAC) general circulation model, an explicit treatment of the isotope effects on the global scale is now possible. The expanded model system has been applied to simulate the chemical system containing up to five isotopologues of all carbon- and oxygen-bearing species, which ultimately determine the δ13C, δ18O and Δ17O isotopic signatures of atmospheric CO. As model input, a new stable isotope-inclusive emission inventory for the relevant trace gases has been compiled. The uncertainties of the emission estimates and of the resulting simulated mixing and isotope ratios have been analysed. The simulated CO mixing and stable isotope ratios have been compared to in-situ measurements from ground-based observatories and from the civil-aircraft-mounted CARIBIC−1 measurement platform.rnrnThe systematically underestimated 13CO/12CO ratios of earlier, simplified modelling studies can now be partly explained. The EMAC simulations do not support the inferences of those studies, which suggest for CO a reduced input of the highly depleted in 13C methane oxidation source. In particular, a high average yield of 0.94 CO per reacted methane (CH4) molecule is simulated in the troposphere, to a large extent due to the competition between the deposition and convective transport processes affecting the CH4 to CO reaction chain intermediates. None of the other factors, assumed or disregarded in previous studies, however hypothesised to have the potential in enriching tropospheric CO in 13C, were found significant when explicitly simulated. The inaccurate surface emissions, likely underestimated over East Asia, are responsible for roughly half of the discrepancies between the simulated and observed 13CO in the northern hemisphere (NH), whereas the remote southern hemisphere (SH) compositions suggest an underestimated fractionation during the oxidation of CO by the hydroxyl radical (OH). A reanalysis of the kinetic isotope effect (KIE) in this reaction contrasts the conventional assumption of a mere pressure dependence, and instead suggests an additional temperature dependence of the 13C KIE, which is driven by changes in the partitioning of the reaction exit channels. This result is yet to be confirmed in the laboratory.rnrnApart from 13CO, for the first time the atmospheric distribution of the oxygen mass-independent fractionation (MIF) in CO, Δ17O, has been consistently simulated on the global scale with EMAC. The applicability of Δ17O(CO) observations to unravelling changes in the tropospheric CH4-CO-OH system has been scrutinised, as well as the implications of the ozone (O3) input to the CO isotope oxygen budget. The Δ17O(CO) is confirmed to be the principal signal for the CO photochemical age, thus providing a measure for the OH chiefly involved in the sink of CO. The highly mass-independently fractionated O3 oxygen is estimated to comprise around 2% of the overall tropospheric CO source, which has implications for the δ18O, but less likely for the Δ17O CO budgets. Finally, additional sensitivity simulations with EMAC corroborate the nearly equal net effects of the present-day CH4 and CO burdens in removing tropospheric OH, as well as the large turnover and stability of the abundance of the latter. The simulated CO isotopologues nonetheless hint at a likely insufficient OH regeneration in the NH high latitudes and the upper troposphere / lower stratosphere (UTLS).rn

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Troposphärisches Ozon ist bekannt als wichtiges Oxidationsmittel und als Vorläufergas hoch reaktiver Radikale. Es zählt zu den wichtigsten Treibhausgasen und wirkt bei hohen Konzentrationen an der Erdoberfläche giftig für alle Lebewesen. Zwar wird der Großteil des troposphärischen Ozons photochemisch produziert, ein erheblicher Anteil hat aber stratosphärischen Ursprung und wird entlang von Tropopausenfalten in Zyklonen in die Troposphäre transportiert. Dieser Transport von Luftmassen aus der Stratosphäre in diernTroposphäre (STT) kann zu einem kurzzeitigen, starken Ozonanstieg am Boden führen und langfristig die Chemie der Troposphäre beeinflussen. Die Quantifizierung des Ozoneintrages und die Identifizierung der dafür verantwortlichen Prozesse ist mit großen Unsicherheiten belastet und ein aktuelles Forschungsthema.rnAufgrund ihrer groben Auflösung ist es mit globalen Modellen nicht möglich, die Details dieser STT-Prozesse zu erfassen. Deshalb wird in dieser Arbeit das Modellsystem MECO(n) genutzt, welches das regionale Atmosphärenchemie- und Klimamodell COSMO/MESSy mit dem globalen Chemie-Klimamodell ECHAM5/MESSy (EMAC) koppelt. Eine einheitliche Prozessparametrisierung ermöglicht konsistente, simultane Simulationen in verschiedenen Modellauflösungen. Ein als Teil dieser Arbeit neu entwickeltes Submodell erlaubt die Initialisierung künstlicher, passiver Tracer in Abhängigkeit verschiedener Variablen. Mit einem auf diese Weise freigesetzten, stratosphärischen Tracer lässt sich Ozon mit stratosphärischer Herkunft von solchem, das photochemisch produziert wurde, unterscheiden.rnIm Rahmen einer Fallstudie werden die Austauschprozesse an einer Tropopausenfalte sowohl aus der Eulerischen, als auch aus der Lagrangeschen Perspektive betrachtet. Die Analyse der STT-Prozesse zeigt, dass Luftmassen aus der Stratosphäre durch turbulente und diabatische Prozesse am Rand der Tropopausenfalte in die Troposphäre gelangen und anschließend bis zum Boden transportiert werden. Diese absinkenden, stratosphärischen Luftmassen führen in den Simulationen zu Ozonanstiegen am Boden, die mit Beobachtungsdaten evaluiert werden können. Es wird gezeigt, dass die Ergebnisse der feiner auflösendenrnModellinstanz gut mit den Messungen übereinstimmen.rnIn einer Lagrangeschen Analyse lassen sich Mischungszeitskalen für STT-Prozesse bestimmen. Es wird gezeigt, dass Luftpakete, die sich länger als zehn Stunden in der Troposphäre aufhalten, diese durch den Eintrag ihrer stratosphärischen Tracereigenschaften beeinflussen und daher nicht vernachlässigbar sind. Eine weitere Studie gibt Aufschluss über die Effektivität der Mischung an Tropopausenfalten: Fast die gesamte Luftmasse, die sich zu einem bestimmten Zeitpunkt in der Tropopausenfalte befindet, gelangt innerhalb von zwei Tagen in die Troposphäre.