Robustness of spatial ranges of environmental chemicals to changes in model dimension     

H. Held 《Stochastic Environmental Research and Risk Assessment (SERRA)》2003,17(1-2):20-41

 A comparison is made between a circular and a more adequate spherical reaction-diffusion multi-media mass balance model. This comparison adds new aspects to ongoing debates about more effective assessments of potentially harmful substances including persistent organic pollutants (POPs). The circular model serves as a paradigm in investigations of persistence and spatial range of non-polar chemicals. An analytic solution of the spherical model is presented. It is utilized in order to establish circular spatial ranges as versatile approximations of their spherical counterparts for most cases. Deviations in the few exceptions are demonstrated as playing a minor role compared to sensitivities against parameter uncertainties which characterize these exceptional cases as well. The sensitivities are fundamentally linked to the multi-scale nature of the underlying system. Finally, the insensitivity of spatial ranges with respect to dimension – circle versus sphere – is further secured by extensive studies of the role of the mode of entry for which a set of rules is established. Present address: Potsdam Institute for Climate Impact Research P.O. Box 60 12 03, D-14412 Potsdam, Germany e-mail: held@pik-potsdam.de The author would like to thank B. H. Hawkins, H. A. Schweers, and M. Str?be for helpful comments.  相似文献   

关于抚顺矿震活动趋势分析   总被引：3，自引：0，他引：3  

孙文福  周元夫  焦明若  冀林旺 《高原地震》2002,14(2):45-51

依据1988年以来抚顺矿震资料，用李治平等人建立的矿山地震能量冈贝尔Ⅰ型极值分布模型，并结合其它地震活动性分析方法，对抚顺矿震活动危险性进行了研究。结果认为：近几年矿震活动水平急剧增强与矿区断裂构造活动无关，主要是由于煤矿采掘所致；今后一定时期内，如果采矿条件不变，矿震活动频次和强度可能仍分别按约33.3次/年和0.08级/年自然增长速度增长；未来几年内矿震的最大强度为Ml4.0左右（概率为0.58-0.72）。  相似文献   

论地质灾害风险评价   总被引：25，自引：0，他引：25  

张业成  张梁 《地质灾害与环境保护》1996,7(3):1-6

地质灾害风险，是指地质灾害活动及其以地人类生命财产造成破坏损失的可能。地质灾害风险具有必然万籁 、随机性、模性、不均稀性等特点。按地质灾害风险评价区域范围，分为点评价、面评价、区域评价。基本内容包括危险性评价、易损性评价、破坏损失评价、防治工程价，由此构成多层次的评价系统。  相似文献   

Methods for the estimation of loss of life due to floods: a literature review and a proposal for a new method   总被引：9，自引：5，他引：4  

S. N. Jonkman  J. K. Vrijling  A. C. W. M. Vrouwenvelder 《Natural Hazards》2008,46(3):353-389

This article deals with methods for the estimation of loss of life due to flooding. These methods can be used to assess the flood risks and to identify mitigation strategies. The first part of this article contains a comprehensive review of existing literature. Methods have been developed for different types of floods in different regions. In general these methods relate the loss of life in the flooded area to the flood characteristics and the possibilities for evacuation and shelter. An evaluation showed that many of the existing methods do not take into account all of the most relevant determinants of loss of life and that they are often to a limited extent based on empirical data of historical flood events. In the second part of the article, a new method is proposed for the estimation of loss of life caused by the flooding of low-lying areas protected by flood defences. An estimate of the loss of life due to a flood event can be given based on: (1) information regarding the flood characteristics, (2) an analysis of the exposed population and evacuation, and (3) an estimate of the mortality amongst the exposed population. By analysing empirical information from historical floods, new mortality functions have been developed. These relate the mortality amongst the exposed population to the flood characteristics. Comparison of the outcomes of the proposed method with information from historical flood events shows that it gives an accurate approximation of the number of observed fatalities during these events. The method is applied to assess the consequences for a large-scale flooding of the area of South Holland, in the Netherlands. It is estimated that the analysed coastal flood scenario can lead to approximately 3,200 fatalities in this area.

A. C. W. M. VrouwenvelderEmail:

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A risky business: Mining, rent and the neoliberalization of “risk”     

Jody Emel  Matthew T. Huber   《Geoforum》2008,39(3):1393-1407

Natural resource investment in the mining sector is often mediated through conflicts over rent distribution between corporate capital and landowner states. Recent rounds of neoliberal policy promoted by the World Bank have highlighted the need for landowner states to offer incentives in order to attract “high risk” capital investment. In Sub-Saharan Africa, in particular, countries have been pushed to offer attractive fiscal terms to capital, thereby lowering the proportion traditionally called rent. This paper examines how the concept of “risk” has been mobilized to legitimate such skewed distributional arrangements. While certain conceptions of social and ecological “risk” have been prevalent in political and social theoretic discourse on mining, such focus elides the overwhelming contemporary power of our notion of “neoliberal risk” – or the financial/market risks – in actually setting the distributional terms of mineral investment. We illustrate our argument by examining the nexus of World Bank mining policy promotion and Tanzanian policy in the late 1990s meant to attract foreign direct investment in gold production. In closing, we suggest that just as “risk” is used to legitimate attractive fiscal terms for investment, recent events highlight how skewed distribution of benefits may set into motion risks that corporate capital had not bargained for.  相似文献   

中小河流域暴雨洪涝灾害风险评估及效果检验   总被引：1，自引：0，他引：1  

谢五三  宋阿伟  田红 《气象科学》2018,38(2):264-270

本文基于FloodArea水动力模型及WRF模式,运用气象资料、水文资料、地理信息资料、社会经济统计资料以及灾情调查资料等,以长江一级支流的秋浦河流域为研究区,开展中小河流域暴雨洪涝灾害风险评估及效果检验。结果表明:FloodArea模型对洪水的淹没范围、淹没水深以及淹没历时等具有较好的模拟效果,可用于中小河流域暴雨洪涝灾害风险评估与预警业务,并由此初步建立了包含模式降水预报→面雨量计算→洪涝淹没模拟→风险评估→预警发布→效果检验等环节的暴雨洪涝灾害风险评估及效果检验业务流程,实现从以往常规的强降水预报到暴雨洪涝灾害预报的业务延伸,可进行推广应用。  相似文献   

The crime kaleidoscope: A cross-jurisdictional analysis of place features and crime in three urban environments     

《Applied geography (Sevenoaks, England)》2017

Research identifies various place features (e.g., bars, schools, public transportation stops) that generate or attract crime. What is less clear is how the spatial influence of these place features compares across relatively similar environments, even for the same crime. In this study, risk terrain modeling (RTM), a geospatial crime forecasting and diagnostic tool, is utilized to identify place features that increase the risk of robbery and their particular spatial influence in Chicago, Illinois; Newark, New Jersey; and Kansas City, Missouri. The results show that the risk factors for robbery are similar between environments, but not necessarily identical. Further, some factors were riskier for robbery and affected their surrounding landscape in different ways that others. Consistent with crime pattern theory, the results suggest that the broader organization of the environmental backcloth affects how constituent place features relate to and influence crime. Implications are discussed with regard to research and practice.  相似文献   

Clustering stochastic point process model for flood risk analysis   总被引：7，自引：0，他引：7  

Z. X. Xu  J. Y. Li  K. Ito 《Stochastic Environmental Research and Risk Assessment (SERRA)》1998,12(1):53-64

Since the introduction into flood risk analysis, the partial duration series method has gained increasing acceptance as an appealing alternative to the annual maximum series method. However, when the base flow is low, there is clustering in the flood peak or flow volume point process. In this case, the general stochastic point process model is not suitable to risk analysis. Therefore, two types of models for flood risk analysis are derived on the basis of clustering stochastic point process theory in this paper. The most remarkable characteristic of these models is that the flood risk is considered directly within the time domain. The acceptability of different models are also discussed with the combination of the flood peak counted process in twenty years at Yichang station on the Yangtze river. The result shows that the two kinds of models are suitable ones for flood risk analysis, which are more flexible compared with the traditional flood risk models derived on the basis of annual maximum series method or the general stochastic point process theory. Received: September 29, 1997  相似文献   

Long-range atmospheric transport of trace metals: the need for geoscience perspectives   总被引：1，自引：1，他引：0  

P. E. Rasmussen 《Environmental Geology》1998,33(2-3):96-108

 The scientific literature of the past 25 years indicates a lack of consensus over the relative significance of anthropogenic and natural sources of metals in rural and remote ecosystems, meaning areas located several hundred to several thousand kilometers from industrial point sources. Geoscience perspectives are needed to address the critical information gaps associated with this issue, particularly where information on the significance and variability of naturally occurring metals is required. Uncertainties in source apportionment need to be addressed by improving methods of fingerprinting sources of airborne particles, and establishing identities of individual particles on the basis of characteristic morphologies and chemical composition. Further research is required to obtain robust estimates of total metal emissions to the atmosphere and to the oceans in order to determine the relative contribution from anthropogenic sources. Such research must involve a systematic attempt to obtain spatially and temporally representative data on the natural release of metals at the global scale. Moreover, a clear understanding of all local natural and anthropogenic loadings to an ecosystem is required before firm conclusions can be drawn about the relative importance of long-range atmospheric transport. Received: 31 October 1996 · Accepted: 27 May 1997  相似文献   

Safety culture and hazard risk perception of Australian and New Zealand maritime pilots   总被引：1，自引：0，他引：1  

R.M. Darbra  J.F.E. Crawford  C.W. Haley  R.J. Morrison 《Marine Policy》2007,31(6):736-745

A survey of the safety culture and hazard risk perception has been carried out involving 77 maritime pilots around Australia and New Zealand, representing more than the 20% of the maritime pilots in each country, in proportional geographic distribution. In 82% of the cases, interviews were carried out face-to-face, based on a questionnaire designed to be completed in less than 1 hour. Questions on 4 different aspects were asked, relating to each pilot's professional background, safety culture and perception of risks, navigation and pilotage hazards and their perception of the pilot's role. The responses indicated that there are issues with regulator identification, commercial pressures on pilots in some locations, incident reporting mechanisms and feedback, training opportunities and improved bridge resource management. In addition to reviewing comments made by pilots, the paper also presents recommendations for consideration in improving operational performance and safety of navigation in ports and regulated waterways. These recommendations can be used by regulators to improve their performance concerning pilotage matters and understand pilots’ concerns.  相似文献