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GOSAC: globale Speicherung anthropogenen Kohlenstoffs in den Ozeanen

Das Projekt "GOSAC: globale Speicherung anthropogenen Kohlenstoffs in den Ozeanen" wird vom Umweltbundesamt gefördert und von Universität Bern, Physikalisches Institut, Abteilung für Klima- und Umweltphysik durchgeführt. This study has three primary objectives: (1) to better quantify past, present, and future C02 uptake by the ocean, which is limited by relatively slow natural processes; (2) to evaluate global aspects of the proposal which offers to artificially accelerate ocean storage of C02 by diverting C02 emissions from fossil-fuel fired power plants directly into the abyss, thereby short-circuiting the natural process; and (3) to assess if predictions stemming from the first two objectives are reasonable, by paying close attention to model validation. Here, seven independantly developed 3-D ocean models from Europe jointly seek European Community support to participate in the Ocean Carbon-Cycle Model Intercomparison Project (OCMIP), an IGBP/GAIM initiative begun in 1995 to compare and validate ocean carbon-cycle models of the global ocean (Objective 1). Support is further sought to use these same models to assess one potential means to help mitigate increasing concentrations of atmospheric C02: deep-ocean C02 disposal (Objective 2). Model validation (Objective 3) is necessary to determine if any envelope of model predictions is likely to bracket real ocean behavior. The ocean is by far the largest reactive reservoir of carbon on earth. Most anthropogenic C02 will one day be stored there, despite relatively slow oceanic uptake which cannot keep pace with excess C02 emissions to the atmosphere. Ocean models provide the best means to assess past and present oceanic C02 uptake; they provide the only means to predict future changes. Comparison and validation of global ocean models is crucial to improving the large uncertainties associated with our understanding of the ocean's role in the global carbon cycle. Well validated ocean models offer our only tool to assess how ocean uptake will change due to future changes in ocean chemistry, biology, and circulation. This effort will assess how changes in ocean carbonate chemistry will effectively reduce oceanic uptake, and how differences in biology and circulation between some of the models may affect results. Ocean models have shown that certain strategies to artificially enhance ocean C02 uptake, such as iron fertilization, would be inefficient at sequestering additional C02; conversely, direct injection of excess C02 appears promising, but only one 3-D model has begun to assess its effectiveness. Prime Contractor: Centre National de la Recherche Scientifique, FU 0005 - Institut Pierre-Simon Laplace; Guyancourt/France.

WINTEX: Wechselwirkungen Landoberflaeche/Atmosphaere in einer winterlichen borealen Landschaft - Planung einer NOPEX-Winter-CFE

Das Projekt "WINTEX: Wechselwirkungen Landoberflaeche/Atmosphaere in einer winterlichen borealen Landschaft - Planung einer NOPEX-Winter-CFE" wird vom Umweltbundesamt gefördert und von Eidgenössische Technische Hochschule Zürich (ETHZ), Institut für Terrestrische Ökologie ITOE durchgeführt. The Continuous Climate Monitoring (CCM) programme consists of two main field micro-meteorological and actinometric stations together with four research catchments. Two CFEs have been carried out in the spring and summers of 1994 and 1995. Since the main objective of NOPEX is to study the annual and daily cycles of the regional land-surface budgets of energy, water, and CO2, plans have been to perform a third CFE during winter conditions. A full-scale such experiment will be very resourcedemanding and must be very carefully planned in order to minimise risks with a failure. It is the objective of this proposal to perform this planning. Measurable objectives is to provide this planning through the following activities: (1) Use of mesoscale atmospheric models, tested over the NOPEX area with data from the CFE1 and CFE2, to test various hypotheses for processes which are likely to be important in winter conditions and to perfom sensitivity analyses of these models; (2) Use of hydrological models including dynamics of snow and frozen soils. Such models will be tested against measurements from various types of land surfaces. Remote-sensing data coupled with GIS techniques will be used to make modelling results available as lower boundary conditions in the meso-scale atmospheric modelling; (3) Evaluate remote-sensing techniques to test and develop algorithms describing facets of the NOPEX winter-time landscape. The remote-sensing data will be carefully integrated with the requirements from the modelling groups in the project; (4) Perform a limited pilot experiment to test measurement equipment in order to earn practical experience in the special climatic problems to be encountered during winter conditions (freezing temperatures, long nights, low solar angles, snow fall blowing past precipitation gauges etc...). Such tests will specifically be made within the NOPEX CCM (Continuous Climate Monitoring) programme (running since May 1994) to improve the chances for this to deliver unbroken data series also during harsh as well as rapidly changing winter conditions and to guarantee availability of data from climatic events that occur seldom but which may have a large importance for the budgets of water, energy and carbon. Frost, hydrology, interception, meteorology, NOPEX, remote sensing, snow, soil, winter.

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