16 resultados para Athena


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The sensitivity to the horizontal resolution of the climate, anthropogenic climate change, and seasonal predictive skill of the ECMWF model has been studied as part of Project Athena—an international collaboration formed to test the hypothesis that substantial progress in simulating and predicting climate can be achieved if mesoscale and subsynoptic atmospheric phenomena are more realistically represented in climate models. In this study the experiments carried out with the ECMWF model (atmosphere only) are described in detail. Here, the focus is on the tropics and the Northern Hemisphere extratropics during boreal winter. The resolutions considered in Project Athena for the ECMWF model are T159 (126 km), T511 (39 km), T1279 (16 km), and T2047 (10 km). It was found that increasing horizontal resolution improves the tropical precipitation, the tropical atmospheric circulation, the frequency of occurrence of Euro-Atlantic blocking, and the representation of extratropical cyclones in large parts of the Northern Hemisphere extratropics. All of these improvements come from the increase in resolution from T159 to T511 with relatively small changes for further resolution increases to T1279 and T2047, although it should be noted that results from this very highest resolution are from a previously untested model version. Problems in simulating the Madden–Julian oscillation remain unchanged for all resolutions tested. There is some evidence that increasing horizontal resolution to T1279 leads to moderate increases in seasonal forecast skill during boreal winter in the tropics and Northern Hemisphere extratropics. Sensitivity experiments are discussed, which helps to foster a better understanding of some of the resolution dependence found for the ECMWF model in Project Athena

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This article traces the paradoxical impact of Weber's oeuvre on two major scholars of nationalism, Ernest Gellner and Edward Shils. Both these scholars died in 1995, leaving behind a rich corpus of writings on the nation and nationalism, much of which was inspired by Max Weber. The paradox is that although neither scholar accepted Weber's sceptical attitude to the concept of ‘nation’, they both used his other major concepts, such as ‘rationality’, ‘disenchantment’, ‘unintended consequences’, the ‘ethic of responsibility’ and ‘charisma’, in their very analyses of the nation and nationalism. And they both saw, each in his own way, the nation and nationalism as constitutive elements of modern societies. However, the paradox ceases being a paradox if one sees the integration, by Shils and Gellner, of concepts of the nation and of nationalism in the analysis of modernity, as a development of Weber's ideas.