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61.
Land surface parameterization schemes play a significant role in the accuracy of meso-local scale numerical models by accounting for the exchange of energy and water between the soil and the atmosphere. The role of land surface processes during large-scale cold-pooling events was studied with two land surface schemes (LSMs) in the Advanced Research Weather Forecasting model (ARW). Model evaluation was complex due to the surface and boundary layer interactions at different temporal and spatial scales as revealed by a scale dependent variance analysis. Wavelet analysis was used for the first time to analyze the model errors with specific focus on land surface processes. The ARW model was also evaluated for the formation of a low-level jet (LLJ). It is shown that vertical resolution in the model boundary layer played a significant role in determining the characteristics of LLJ, which influenced the lower boundary layer structure and moisture distribution. The results showed that the simulated low-level jet over southern Georgia was sensitive to the land surface parameterization and led to a significant difference in the boundary layer exchange. The jet shear played a crucial role in the maintenance of turbulence and weak shear caused excessive radiative cooling leading to unrealistic cold pools in the model. The results are important for regional downscaling as the excessive cold pools that are simulated in the model can go unnoticed.  相似文献   
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A quantitative estimate of the influence on the temperature mode of perennially frozen rocks in the Pechorsk coal basin caused by pollution of the surface by coal dust was undertaken.  相似文献   
63.
Conventional sectoral management and piecemeal governance are considered less and less appropriate in pursuit of sustainable development. Ecosystem based marine spatial management (EB-MSM) is an approach that recognizes the full array of interactions within an ecosystem, including human uses, rather than considering single issues, species, or ecosystem services in isolation. Marine spatial planning and ocean zoning are emerging concepts that can support EB-MSM. EB-MSM is driven by high-level goals that managers aim to achieve through the implementation of measures. High-level goals and objectives need to be translated into more operational objectives before specific targets, limits and measures can be elaborated.Monitoring, evaluation and adaptation are necessary to ensure that marine management measures are both effective and efficient. Solid monitoring frameworks are the foundation of adaptive management, as they provide the necessary information to evaluate performance and the effectiveness of management actions. Marine protected areas (MPAs) - possibly set up in networks - constitute a key component in EB-MSM policies and practises and have been applied as a cornerstone in conservation of marine biodiversity, management of fish populations, development of coastal tourism, etc. Moreover, MPA experiences have provided methods and concepts (such as zoning) to a wider EB-MSM context. The assignment of values to biophysical features of the marine environment allows the direct assessment of related management choices and may assist EB-MSM.A range of monetary valuation techniques have been proposed to reduce attributes of goods and services to a single metric. However, in the marine environment such an approach is often over simplistic, and thus less reductive techniques may be necessary. Rather than producing a single metric, the results of non-monetary assessments guide policy allowing weight to be given as necessary to potential areas of conflict and consensus.Strategies to take into account climate change effects and geohazard risks in EB-MSM have been applied or proposed worldwide. EB-MSM regimes must be alert to such risks and flexible to account for changes.  相似文献   
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Abstract

This article examines the micro-politics of belonging in the post-socialist outskirts of Berlin, in Marzahn, one of many new urban immigrant settlement areas in Europe. More specifically, it focuses on what locals perceive as an acceptance-precluding conspicuous presence of nominally white immigrants of German ancestry from the former Soviet Union, the Aussiedler (resettlers). Long-term residents read and interpret these immigrants’ everyday embodiments by constructing what I call micro-economies of embodied difference in order to mark immigrants as non-belonging Eastern-European. In order to make sense of such practices and local antipathy towards the Aussiedler, I analyze the embeddedness of this suburban locality in the regional politics of belonging, showing how Marzahn and its long-time residents have themselves become post-wall Berlin's (and Germany's) internal Others, saturated with uncommodifiable traces of now-denigrated state-socialist Easternness. I suggest that in such a context these residents’ practice of ascribing the unwanted Easternness to recent immigrants works to deflect it in order to buttress their own claims to full membership citizenship in the unified Germany from which they have long been excluded. [Key words: belonging, immigrants, embodied difference, Othering, Easternness, Berlin.]  相似文献   
67.
In the present work, geological and geophysical methods were used to delineate the locations of multiple mafic intrusions at the Claytor Nature Study Center (CNSC) near Bedford, VA. An investigation of the groundwater hydrology of CNSC was launched in 2007. As a first step in that project a preliminary geological survey revealed sparse evidence of a number of diabase intrusions in the area. While diabase intrusions are not particularly permeable features, contact metamorphism of the host rock could provide conduits for groundwater due to stress fractures and joints and high-temperature recrystallization of the rock matrix. Following the geological survey, geophysical surveys including seismic refraction, ground penetrating radar, and magnetic ground measurements were conducted to determine the location and extent of these multiple igneous intrusions. Seismic and radar surveys proved to be inconclusive, but the magnetic surveys showed strong magnetic anomalies. The magnetic data were obtained using a Geometrics G-856 proton precession magnetometer and were interpreted using the Mag2dc algorithm and SGeMS geostatistical software. The results show that the intrusions are dikes that cut across nearly perpendicular to the regional metamorphic structures and trend generally north–south with a dip of approximately 75°–90° to the west. These findings are consistent with one of the general directions of stresses associated with the North Atlantic seafloor spreading in late Triassic or early Jurassic period. Subsequent hydrologic testing and groundwater modeling confirm the role of the dikes in the overall hydrogeology of the site.  相似文献   
68.
The stratigraphy of the Taman Peninsula is defined using the sections at Zelensky Hill ?? Panagia, Popov Kamen, Taman and Zheleznyi Rog. The stratigraphy is constructed from distribution of mollusks, foraminifers, nannofossils, diatoms, and organic-walled phytoplankton, as well as incorporating paleomagnetic data. The occurrence of oceanic diatom species in the Middle-Upper Sarmatian, Maeotian and Lower Pontian makes a direct correlation possible between the sections studied, the Mediterranean basin and oceanic zonation. The new data on planktonic and benthic biotic groups suggests a pulsating connection of the Eastern Paratethys with the open marine basins, especially during transitional intervals within constant environments. Comprehensive studies of the Chokrakian-Kimmerian microbiota provide evidence for several levels of marine microbiotic associations that are related to short-term marine invasions. The biotic and paleomagnetic data of the Taman Peninsula sections give a more comprehensive, but sometimes a controversial picture on the Eastern Paratethys history and the nature of its relationship with the adjacent marine basins.  相似文献   
69.
Mathematical Geosciences - Multiple point statistics (MPS) algorithms allow generation of random fields reproducing the spatial features of a training image (TI). Although many MPS techniques offer...  相似文献   
70.
The integration of information obtained from onshore and offshore geological and geophysical research undertaken in the context of the International Polar Year has led to the following results. The continental crust is widespread in the Arctic not only beneath the shelves of polar seas in the framework of the Amerasia Basin but also in the Chukchi-Northwind, Lomonosov, and Mendeleev ridges; a combination of continental and oceanic crusts is inferred in the Alpha Ridge. The Amerasia Basin is not an indivisible element of the Arctic Ocean either in genetic or structural terms but consists of variously oriented basins different in age. The first, Mesozoic “minor ocean” of the Arctic Ocean—the Canada Basin—arose as a result of impact of the Arctic plume on the high-latitude region of Pangea. This inference is supported by the vast Central Arctic igneous province that comprises the Jurassic-Mid-Cretaceous within-plate and ocean-island basaltic and associated rocks. The rotational mechanism of opening of this basin is explained by the slant path of the plume head motion, which resulted in breaking-off and displacement of a fragment of Pangea. The effect of the Arctic plume was expressed during all stages of the opening of the Canada Basin and exerted effects on the adjacent part of the Eurasian continent during the formation of the Verkhoyansk-Chukotka tectonic domain. The Canada Basin was an element of the segmented system of Atlantic spreading ridges, while the Arctic plume that initiated its evolution was genetically related to the episodically acting African-Atlantic superplume. In comparison with the Pacific superplume, the low productivity of African-Atlantic lower mantle upwelling became the cause of slow and ultraslow spreading in the Atlantic and Arctic oceans and determined the passive character of their margins, including the Canada Basin.  相似文献   
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