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Natural Hazards - Analysis of precipitation trends as well as the observed trends in precipitation concentration can be useful tools for the identification of natural hazards. This study aimed to...  相似文献   
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Boundary-Layer Meteorology - An analysis based on the law of linear momentum conservation demonstrates unequivocally that the mass fraction is the scalar whose gradient determines gas diffusion,...  相似文献   
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We present new U-Pb zircon and monazite ages from the Sunsas belt granitic magmatism in Bolivia,SW Amazonian Craton.The geochronological results revealed four major magmatic events recorded along the Sunsas belt domains.The older igneous event formed a granitic basement coeval to the Rio Apa Terrane(1.95-1.85 Ga)in the southern domain.The second magmatic episode is represented by 1.68 Ga granites associated to the Paraguá Terrane(1.69-1.66 Ga)in the northern domain.The 1.37-1.34 Ga granites related to San Ignacio orogeny represent the third and more pervasive magmatic event,recorded throughout the Sunsas belt.Moreover,magmatic ages of~1.42 Ga revealed that the granitogenesis asso-ciated to the Santa Helena orogeny also affected the Sunsas belt,indicating that it was not restricted to the Jauru Terrane.Lastly,the 1.10-1.04 Ga youngest magmatism was developed during the Sunsas oro-geny and represents the final magmatic evolution related to Rodinia assembly.Likewise,the 1.95-1.85 and 1.68 Ga inherited zircon cores obtained in the~1.3 Ga and 1.0 Ga granite samples suggest strong par-tial melting of the Paleoproterozoic sources.The 1079±14 Ma and 1018±6 Ma monazite crystallization ages can be correlated to the collisional tectono-thermal event of the Sunsas orogeny,associated to reac-tions of medium-to high-grade metamorphism.Thus,the Sunsas belt was built by heterogeneous 1.95-1.85 Ga and 1.68 Ga crustal fragments that were reworked at 1.37-1.34 Ga and 1.10-1.04 Ga related to orogenic collages.Furthermore,the 1.01 Ga monazite age suggests that granites previously dated by zir-con can bear evidence of a younger thermal history.Therefore,the geochronological evolution of the Sunsas belt may have been more complex than previously thought.  相似文献   
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We study the scale dependence of the saturated hydraulic conductivity Ks through the effective porosity ne by means of a newly developed power‐law model (PLM) which allows to use simultaneously measurements at different scales. The model is expressed as product between a single PLM (capturing the impact of the dominating scale) and a characteristic function κ? accounting for the correction because of the other scale(s). The simple (closed form) expression of the κ?‐function enables one to easily identify the scales which are relevant for Ks. The proposed model is then applied to a set of real data taken at the experimental site of Montalto Uffugo (Italy), and we show that in this case two (i.e. laboratory and field) scales appear to be the main ones. The implications toward an important application (solute transport) in Hydrology are finally discussed. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
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2012 Emilia earthquake,Italy: reinforced concrete buildings response   总被引:1,自引:1,他引:0  
Data of the Italian National Institute of Statistics are collected aimed at characterizing Reinforced Concrete (RC) building stock of the area struck by the 2012 Emilia earthquake (number of storeys, age of construction, structural typology). Damage observations, collected right after the event in reconnaissance reports, are shown and analyzed emphasizing typical weaknesses of RC buildings in the area. The evolution of seismic classification for Emilia region and RC buildings’ main characteristics represent the input data for the assessment of non-structural damage of infilled RC buildings, through a simplified approach (FAST method), based on EMS-98 damage scale. Peak Ground Acceleration (PGA) capacities for the first three damage states of EMS-98 are compared with registered PGA in the epicentral area. Observed damage and damage states evaluated for the PGA of the event, in the epicentral area, are finally compared. The comparison led to a fair agreement between observed and numerical data.  相似文献   
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In recent years, physical geography in Mexico has contributed to the enterprise of geographical science by integrating with fields of study closely related to topics of sustainable development. This paper outlines the contribution of the discipline to environmental public policy development, particularly ecological land use planning and integrated watershed management. In terms of applications, physical geography appears to have reached a stage of maturity in Mexico. However, it must offer a stronger leadership in areas such as ecoregional analysis (in an integrated fashion, and not only from the biological‐ecological perspective) and regional vulnerability to global change processes. An excellent opportunity exists for scientists and decision makers to develop a common agenda.  相似文献   
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Understanding public perceptions of climate is critical for developing an effective strategy to mitigate the effects of human activity on the natural environment and reduce human vulnerability to the impacts of climate change. While recent climate assessments document change among various physical systems (e.g., increased temperature, sea level rise, shrinking glaciers), environmental perceptions are relatively under-researched despite the fact that there is growing skepticism and disconnect between climate science and public opinion. This study utilizes a socio-ecological research framework to investigate how public perceptions compared with environmental conditions in one urban center. Specifically, air temperature during an extreme heat event was examined as one characteristic of environmental conditions by relating simulations from the Weather Research and Forecast (WRF) atmospheric model with self-reported perceptions of regional and neighborhood temperatures from a social survey of Phoenix, AZ (USA) metropolitan area residents. Results indicate that: 1) human exposure to high temperatures varies substantially throughout metropolitan Phoenix; 2) public perceptions of temperature are more strongly correlated with proximate environmental conditions than with distal conditions; and 3) perceptions of temperature are related to social characteristics and situational variables. The social constructionist paradigm explains public perceptions at the regional scale, while experience governs attitude formation at the neighborhood scale.  相似文献   
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