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Wolfgang Loibl Johann Züger Mario K?stl 《Standort - Zeitschrift für angewandte Geographie》2009,17(2):94-100
Der letzte Bericht des Intergovernmental Panel on Climate Change (IPCC 2007) erl?utert die weltweiten Auswirkungen des Klimawandels
deutlich – allerdings aus globaler Sicht. Um zu kl?ren wie sich das regionale Klima in ?sterreich ver?ndern wird, wurde mit
dem Projekt „reclip:more“ (Research for Climate Protection: Model Run Evaluation) eine erste kleinr?umige Datenbasis für Klimaschutz
und Klimafolgenforschung für ?sterreich generiert. Klimaszenarien wurden mittels regionaler Klimamodelle (RCMs) für die Alpen
als 10 × 10-Kilometer-Raster und mit anschlie?endem Downscaling für ?sterreich mit einer Zielaufl?sung 1 km entwickelt. Die
RCMs wurden mit ERA-40 Reanalyse-Daten der Vergangenheit und Daten eines Zukunftsszenarios des globalen Klimamodells (GCM)
ECHAM5 angetrieben, um retrospektive (1981 bis 1990) und künftige (2041 bis 2050) Klimadatens?tze für die Alpen zu berechnen
und M?glichkeiten und Unsicherheiten der Modelle und Downscaling-Methoden für die Alpen zu evaluieren. Die nun vorliegenden
Datens?tze und weitere, die im Folgeprojekt „reclip:century“ für alternative Treibhausgasszenarien bis 2100 berechnet werden,
dienen dazu als Basis für Aussagen über ?kologische und sozio?konomische Entwicklungen im Hinblick auf den Klimawandel. 相似文献
33.
Marie‐Hélène Zérah 《Development and change》2009,40(5):853-877
This article questions the participatory dimension of urban governance in Mumbai. Based on surveys of a number of participatory projects for urban services, it compares the differentiated impacts of participation in middle‐class colonies with those in slums. Results demonstrate that changing citizen–government relationships have led to the empowerment of the middle and upper middle class who harness the potential of new ‘invited space’ to expand their claims on the city and political space. In contrast, the poor end up on the losing side as NGOs function more as contracted agents of the State than as representatives of the poor. Direct community participation empowers influential community members, small private entrepreneurs and middlemen, and contributes to labour informalization. Ultimately, these processes consolidate a form of ‘governing beyond the State’ that promotes a managerial vision of participation and leads to double standards of citizenship. 相似文献
34.
A variety of data indicate that the Carbonate aquifer in southern Manitoba is a heterogeneous and anisotropic aquifer wherein groundwater flow follows preferred flow path networks. Specific capacity tests show that aquifer transmissivity can vary by up to four orders of magnitude within 1 km. Geostatistical analysis reveals a strong anisotropy in the transmissivity field, with better spatial continuity in NE–SW and NW–SE directions, coincident with the dominant orientations of fractures observed in bedrock exposures. However, discrepancies between the orientation of highest fracture density and best transmissivity continuity suggest that either additional geological factors control the preferred flow network or there is a biased representation of the fracture pattern because all direct fracture observations came from the northern part of the study area. In an effort to investigate whether the geographically biased fracture data set represents the fracture pattern for the whole region, Landsat images and digital elevation maps were processed to extract linear features that may indicate subsurface fracture zones in areas where bedrock is covered by glacial sediments. The results suggest a consistent fracture pattern throughout the study area, indicating that the two observed fracture groups might have gone through different processes in terms of permeability development. Alteration by mineral cementation and dissolution along fracture surfaces may have preferentially improved the fracture permeability in one orientation, while reducing it in the other. The in situ stress field is also believed to play a major role in the preferred regional flow network. This paper discusses the evidence for the preferred flow path network and possible geological factors controlling aquifer anisotropy in this region. 相似文献
35.
Trevor Z. Yeow Gregory A. MacRae Vinod K. Sadashiva Kazuhiko Kawashima 《Journal of Earthquake Engineering》2013,17(5):750-768
Symmetrically reinforced bridge columns with a horizontal cantilever in one direction, called C-bent columns, tend to deform predominantly in the direction of applied moment when subject to strong earthquake shaking. For this reason, the strength in the direction of applied moment is generally increased in design. This article describes the use of inelastic dynamic time history analyses with a suite of ground motion records to quantify the amount of strength increase required to minimize likely peak and permanent displacement demands. It is shown that the strength should be increased by approximately 2.3 times the applied moment in design. 相似文献
36.
The various types of natural landscapes of West Siberia are analyzed in terms of the environmental impacts of the more common forms of human activity. These are natural gas extraction and reindeer herding in the northern tundra; oil extraction and logging in the middle taiga, and agriculture as well as manufacturing in the southern wooded steppe and steppe. The impacts of human activity on specific natural processes (cryogenesis, bog formation, salinization) are discussed. The territory of West Siberia is broken down into three types of environmental impact regions: regions of significant impacts (from oil and gas extraction and agriculture); regions of moderate impacts (from logging and reindeer herding); and a region in which natural landscape structures have remained virtually unaffected by human activity. 相似文献
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Lead isotope compositions provide a direct means of assessing provenance. The lead contents in bronzes cannot be used to argue against lead isotopes. Any claim for the origin of the source material for the origin of Yin‐Shang bronzes must satisfy the measured lead isotope compositions. Thus far, only southern African sources are found to meet this criteria. 相似文献
40.