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Amtlicher Anzeiger, Teil II des Hamburgischen Gesetz- und Verordnungsblattes

Nach hamburgischem Landesrecht werden Veröffentlichungen durch Abdruck im Hamburgischen Gesetz- und Verordnungsblatt vorgenommen. Rechtsverbindlich ist deshalb ausschließlich die gedruckte Ausgabe des Hamburgischen Gesetz- und Verordnungsblattes Teile I und II (Amtlicher Anzeiger). Eine Inhaltssuche kann nur über die Internetseite der <a href="http://www.luewu.de/anzeiger/">Firma Lütcke & Wulff</a> erfolgen.

CSIRO-PIK Collaboration in assessments of sustainable pathways for feeding 9 billion people (CSIRO - RD1)

Das Projekt "CSIRO-PIK Collaboration in assessments of sustainable pathways for feeding 9 billion people (CSIRO - RD1)" wird vom Umweltbundesamt gefördert und von Potsdam-Institut für Klimafolgenforschung e.V. durchgeführt. The objective of the collaborative agreement is to assess sustainable pathways for feeding 9 billion people. Key dimensions of sustainability to be explored include intensification pathways, water, nutrients, and greenhouse gas (GHG) emissions. The Collaborator (Jens Heinke) will spend 2 months per year at CSIRO to ensure the delivery of project outputs and to foster institutional collaboration. The Collaborator (Jens Heinke) will undertake to: 1. Assess the alteration of nitrogen and phosphorus cycles by livestock production from different animal types, in different world regions and in different production systems. The analysis will build on a detailed representation of the livestock sector from Herrero et al. and previous work by Bouwman et al. The assessment will highlight the different alteration of nutrient cycling by different forms of livestock production providing important insight for sustainable intensification. 2. Comprehensively assess trade-offs between consumptive water use, nutrients, and GHG emissions in global agriculture within a consistent framework. The analysis will build on the previous quantification of alterations of nutrient cycles that completes already existing quantifications of consumptive water use and GHG emissions based on the same detailed representation of the livestock sector, and provide insights on competing goals in the context of sustainable intensification. 3. Participate in the development of 'wedge-based' regional and global models of global food systems in collaboration with Princeton University and INRA. The previous trade-off analysis of water, nutrients, and GHGs will provide a basis for quantifying resources and emission related aspects of different strategies for sustainable intensification. 4. Assist in the development of scenarios of sustainable diets and their impacts on the world food and ecosystems. For this activity, the previous trade-off analysis of water, nutrients, and GHGs will provide the link to resources use and environmental consequences for given scenarios of food consumption.

Tropical High Altitude Clouds and their Impact on Stratospheric Humidity

Das Projekt "Tropical High Altitude Clouds and their Impact on Stratospheric Humidity" wird vom Umweltbundesamt gefördert und von Leibniz-Institut für Troposphärenforschung e.V. durchgeführt. Clouds play a key role in the Earth's climate system by regulation of the incoming and outgoing radiation, chemical and dynamical processes. Ice clouds at high altitudes in the tropics, the so called tropical tropopause layer, are particularly important since this is the main region where air ascends slowly from the troposphere into the dry stratosphere. Thus, these ice clouds affect the stratospheric water vapour content which in itself is a main driver of radiative and chemical processes, e.g. ozone depletion, there. These clouds can either be of convective nature, or occur in convective overshooting cloud turrets, or they form in situ by large scale upwelling and cooling as subvisible cirrus. Although the latter occur frequently, little is known about the exact microphysical formation mechanisms and how they can be maintained. Previous modelling efforts using various different mechanisms, however, have failed to agree with the observed properties. This project aims to improve our knowledge of the impact clouds in the tropical tropopause layer have on stratospheric humidity, by studying their formation, maintenance, and occurrence frequencies.A set of state-of-the-art numerical models will be used to simulate the clouds in the tropical tropopause layer, taking advantage of their particular strengths. These models are the Weather Research and Forecasting (WRF) Model, the GLObal Model of Aerosol Processes (GLOMAP), and the Australian Community Climate and Earth-System Simulator (ACCESS). First, the questions related to the formation and maintenance of subvisible cirrus will be addressed. In a second step the impact of subvisible cirrus and overshooting convection on the stratospheric humidity will be assessed. Both the direct effects (e.g. injection of ice particles into the stratosphere) and indirect effects (e.g. change in dynamical processes) will be studied. In order to estimate the net effect, occurrence frequencies of both cloud types will be derived from a complementary set of ground based remote sensing observations from the Darwin site and satellite observation from the International Satellite Cloud Climatology Project. The data of airborne in situ measurements which I analyzed during my PhD will help to constrain and test the model simulations. A better understanding of the complex processes related to the clouds in the tropical tropopause layer will improve their representation in numerical models and thus, enhance the quality of model predictions. This will improve our ability to constrain climate predictions due to highly uncertain ice cloud processes. Additionally, knowing the impact of these clouds on stratospheric humidity will enable an improved quantification of their climate impact.

How is the stratosphere-troposphere coupling affected by climate change, and how strong is the climate feedback? (SHARP-STC)

Das Projekt "How is the stratosphere-troposphere coupling affected by climate change, and how strong is the climate feedback? (SHARP-STC)" wird vom Umweltbundesamt gefördert und von Deutsches Zentrum für Luft- und Raumfahrt e.V. (DLR), Institut für Physik der Atmosphäre, Abteilung Dynamik der mittleren Atmosphäre durchgeführt. The focus of this project is to determine the role of the interaction between the stratosphere and troposphere in a changing climate, in particular to assess the impact of a changing stratosphere on the troposphere- surface system. Observations and model studies have shown that the troposphere and stratosphere influence each other on different time scales, but the mechanisms responsible are not well understood. Questions that will be addressed also in Phase II of this project are if the importance of the coupling between the stratosphere and the troposphere will change in a changing climate and what the consequences will be for surface climate and weather. Transient simulations of the past and future as well as complementary sensitivity simulations with state-of-the-art Chemistry-Climate models (CCMs) will be performed and analysed to study how well current models are able to reproduce the observed coupling, to understand the responsible mechanisms, and to predict its future evolution. New aspects in Phase II are the extension of our studies to the effects of radiative and chemical coupling processes on the troposphere-surface system. The relevance of additional climate feedback processes associated with ocean coupling will be addressed by applying a CCM with an interactive ocean model. The role of the representation of stratospheric processes for stratosphere-troposphere coupling will be studied in simulations with an Earth System Model (ESM) with different spatial resolutions.

Using the HALO Microwave Package (HAMP) for cloud and precipitation research

Das Projekt "Using the HALO Microwave Package (HAMP) for cloud and precipitation research" wird vom Umweltbundesamt gefördert und von Universität Hamburg, Fachbereich Erdsystemwissenschaften, Meteorologisches Institut durchgeführt. Representation of cloud and precipitation processes is one of the largest sources of uncertainty in climate and weather predictions. This project aims at exploring the potential of the novel HALO microwave package (HAMP) for airborne cloud and precipitation research by participating in all cloud related missions of the research aircraft HALO. HAMP is a unique combination of a 23 channel microwave radiometer and a cloud radar. To make HAMP a valuable research instrument, we will develop synergistic retrieval algorithms which convert the measured passive and active microwave signals into profiles of temperature, humidity and hydrometeor content with corresponding error estimates. A comprehensive evaluation of HAMP with existing observational systems, like e.g. satellites and ground based remote sensing super-sites will allow an assessment of its added value. In particular, we will analyze whether HAMP can resolve the fine-scale structure of cloud and precipitation fields and can thus relate point observations with area averaged data from satellites and models. Finally, observations from the NARVAL campaign will be used to demonstrate the benefit of HAMP for model development by revising the frequently used model assumption that shallow convective clouds do not precipitate.

Current Systems around Terrestrial Planets: EOF Analysis and Modeling

Das Projekt "Current Systems around Terrestrial Planets: EOF Analysis and Modeling" wird vom Umweltbundesamt gefördert und von Jacobs University Bremen gGmbH, Focus Area Health - Physics & Earth Sciences durchgeführt. The magnetosphere of a planet is controlled by a number of factors such as the intrinsic magnetic field, the atmosphere and ionosphere, and the solar wind. Different combinations of these control factors are at work at the terrestrial planets Mercury, Venus, Earth, and Mars, hence they form a very suitable set for quantitative comparative studies. A significant intrinsic dipolar magnetic field is present only on Earth and on Mercury. However, the configuration at Mercury differs considerably from that at Earth because Mercury does not support an atmosphere and ionosphere, the dipolar field is much weaker, the solar wind denser, and the interplanetary magnetic field stronger. Both Mars and Venus have atmospheres but lack a global planetary magnetic field, with regional crustal magnetization being present on Mars. This proposal aims at investigating and comparing electrical current systems in the space environments of terrestrial planets using magnetic vector data collected by orbiting spacecraft such as Venus Express, Mars Global Surveyor, CHAMP (Earth), and MESSENGER (Mercury). We propose to construct data-driven and physically meaningful representations that reveal and quantify the influence of various control factors. To achieve this, we will tailor Empirical Orthogonal Function (EOF) analysis and other multivariate methods to the specifics of planetary magnetic field observations. In contrast to representations that build on predefined functions like spherical harmonics, basis functions in the EOF approach are derived directly from the data. EOFs are designed to extract dominant coherent variations for further interpretation in terms of known physical phenomena, and then, in a regression step, for modeling using suitable control variables. The EOF methodology thus allows quantifying the relative importance of control factors for each planet individually, and thus contributes to the solution of topical science questions. The resulting empirical models will facilitate comparative studies of current systems at the terrestrial planets.

Effective approaches and solution techniques for conditioning, robust design and control in the subsurface

Das Projekt "Effective approaches and solution techniques for conditioning, robust design and control in the subsurface" wird vom Umweltbundesamt gefördert und von Technische Universität Braunschweig, Institut für Wissenschaftliches Rechnen durchgeführt. When predicting processes in the subsurface, the need for uncertainty quantification and risk assessment is evident. Yet, this is merely the first within a full spectrum of tasks in stochastic modelling, which includes calibration, robust design, optimal monitoring and predictive control. Monte-Carlo simulation is the most simple and universally applicable option for stochastic modelling, but its computational costs become strictly prohibitive when joining it with the above follow-up tasks. Polynomial chaos expansions (PCE) are computationally much more efficient, and receive a quickly increasing attention. However, only little work has been done to make PCE available to the full spectrum of tasks. The proposed work will make PCE accessible for the full spectrum of tasks named above. We will develop a new, integrative and efficient framework, where all involved quantities will be treated via an overall functional approximation that represents the systems behaviour within the entire range of un-certain parameters, design or control variables. Thus, the strongly increased computational costs of follow-up tasks will be drastically mitigated. We will further reduce storage requirements and improve computational efficiency via data-sparse and low-rank tensor representations throughout all tasks. The drastic gain in computational efficiency will finally allow tackling advanced follow-up tasks for full-scale, complex and real-world problems, even under uncertainty. We will demonstrate this by application to CO2 injection into the deep subsurface. Site characterization and selection, design and control of injection strategies under uncertainty, as well as optimal monitoring of CO2 leakage to the surface will be performed within the new framework, leading to better assessment, management and reduction of the involved risks.

Combined airborne lidar measurments of moisture transport and cirrus properties: HALO-LIDAR

Das Projekt "Combined airborne lidar measurments of moisture transport and cirrus properties: HALO-LIDAR" wird vom Umweltbundesamt gefördert und von Ludwig-Maximilians-Universität München, Meteorologisches Institut durchgeführt. Humidity in and around cirrus clouds: Radiative effects of cirrus clouds are a major uncertainty in determining the climate cloud feedback. The variability of cirrus on different spatial scales is another major issue which complicates modelling of their radiative properties. Aerosol and water vapour measurements were performed with the DLR lidar system WALES in 2010 during the first mission with the new German research aircraft HALO. ECMWF temperature analyses are used to derive relative humidity inside and outside of cirrus clouds from the lidar water vapour observations. Comparisons with in situ measurements of humidity on the research aircraft Falcon flying inside the cirrus clouds confirm the high accuracy of the WALES system. The study shows the advantages of lidar cross sections to provide additional information about the vertical structure of the complex humidity field, also allowing for simultaneous statistical analyses in different cloud layers. Combined with accurate temperature measurements, the lidar observations have a great potential for detailed statistical cirrus cloud and related humidity studies. Future HALO missions will benefit from the findings and techniques developed here. HSRL aerosol classification: To better understand the effects of aerosols on the climate system it is important to obtain highly accurate information on the aerosol optical properties (e.g., extinction coefficient, single scattering albedo and phase function) as well as on their temporal and spatial distribution. The high spectral resolution lidar (HSRL) method based on an iodine absorption filter and a frequency doubled pulsed Nd:YAG laser, developed at DLR, has the capability to directly measure the extinction and backscatter coefficients of aerosols and clouds. Airborne HSRL data from four different field experiments are used in the frame of this project to build up an aerosol classification. The method is based on HSRL measurements of a set of intensive aerosol properties, in particular the lidar ratio, the particle linear depolarization ratio and the color ratio of backscatter. Applied to the HSRL measurements on ESA's EarthCARE mission it will provide the climate relevant properties extinction coefficient and aerosol optical depth, together with the global, verticallyresolved distribution of aerosols and clouds. Statistical characterization of humidity variability: The distribution of water vapour in the atmosphere shows variability on all spatial scales. An accurate representation of cloud processes in climate models with limited resolution relies on a statistical description of the unresolved structures. A compact description that can describe intermittent variability on many scales is multifractal scaling based on structure functions of different orders. This analysis method was applied to airborne water vapour lidar measurements from a number of field campaigns in midlatitude, polar and subtropical latitudes. The humidity was found to be charact

Quantifying and modelling pathways of soil organic matter as affected by abiotic factors, microbial dynamics, and transport processes (QUASOM)

Das Projekt "Quantifying and modelling pathways of soil organic matter as affected by abiotic factors, microbial dynamics, and transport processes (QUASOM)" wird vom Umweltbundesamt gefördert und von Max-Planck-Institut für Biogeochemie durchgeführt. Soils play a critical role in the coupled carbon-cycle climate system. However, our scientific understanding of the role of soil biological-physicochemical interactions and of vertical transport for biogeochemical cycles is still limited. Moreover the representation of soil processes in current models operating at global scale is crude compared to vegetation processes like photosynthesis. Hence, the general aim of this project is to improve our understanding of the key interactions between the biological and the physicochemical soil systems that are often not explicitly considered in current experimental and modeling approaches and are likely to influence the biogeochemical cycles for a large part of the terrestrial biosphere and thus have the potential to significantly impact the Earth System as a whole. This will be achieved through an approach that integrates new soil mesocosm experiments, field data from ongoing European projects and soil process modeling. In mesocosm tracer experiments the fate of fresh and autochthonous soil organic matter will be followed under varying temperature and moisture regimes in bacterial and fungal dominated soils and the hypothesis tested that transfer coefficients between soil organic matter pools are constant as implemented in current soil organic matter models. A new soil model structure will be developed that may explicitly account for the role of microbes and transport for soil organic matter dynamics. This will be supported by multiple-constraint model identification techniques, which allows testing and achieving model consistency with several observation types. An incorporation of such new soil module into a global dynamic vegetation model (DGVM) is foreseen.

Impact of physically relevant and numerically induced diapycnal mixing and meso-scale dissipation on meridional mass and tracer transports in the Southern Ocean

Das Projekt "Impact of physically relevant and numerically induced diapycnal mixing and meso-scale dissipation on meridional mass and tracer transports in the Southern Ocean" wird vom Umweltbundesamt gefördert und von Leibniz-Institut für Ostseeforschung durchgeführt. The Meridional Overturning Circulation (MOC) in the Southern Ocean (SO) is composed of two limbs, the Upper Circumpolar Deep Water (UCDW) flows polewards and upwards across the Antarctic Circumpolar Current (ACC), upwells to the surface at the poleward flank of the ACC and then returns equatorwards as a near surface current. This upper limb is known to be largely adiabatic. In contrast to that, the lower limb of the MOC formed by the Lower Circumpolar Deep Water (LCDW) upwells closer to Antarctica, cools down substantially near the surface and convects down at high turbulent mixing to form the Antarctic Bottom Water (AABW). While the adiabatic upper limb is driven by an imbalance of a northward Ekman transport and an opposing meso-scale eddy transport, the dynamics of the lower limb is more complex due to the additional significance of diapycnal mixing. Thus, a good quantification of these dynamics requires a correct representation of both small-scale (diapycnal) and meso-scale (lateral) eddy mixing. On the other hand, it has long been known that in particular in the SO, large numerical mixing and dissipation in ocean circulation models due to the discretisation of the advection terms obscures the representation of diapycnal mixing and thus strongly limits the predictability of ocean models. It is therefore the aim of this project to use and to further develop a novel analysis tools for numerical mixing and dissipation to quantify effective mixing and dissipation, given by the sum of explicitly parameterised and numerically induced values. By estimating realistic effective mixing and dissipation rates, using our combined expertise of numerical mathematics and small-scale turbulence parameterisation and large-scale high-resolution modelling, we are able to the first time to assess the sensitivity of realistic models of the SO to diapycnal mixing and numerical dissipation and to understand the interplay between meso-scale (lateral) and small-scale (diapycnal) eddy mixing on the lower limb of the MOC.

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