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191.
Numerical Simulation of the 1918 Puerto Rico Tsunami 总被引:1,自引:0,他引:1
The Caribbean Sea region is well known for its hurricanes, and less known for tsunamis. As part of its responsibilities in hazard assessment and mitigation, the U.S.A. Federal Emergency Management Agency, and the Puerto Rico Civil Defense, funded a pilot study to perform a numerical simulation of the 1918 Puerto Rico tsunami, one of the most deadly in the region. As part of the study a review has been made of the tectonic and tsunamigenic environment around Puerto Rico, the fault parameters for the 1918 event have been estimated, and a numerical simulation has been done using a tsunami propagation and runup model obtained through the Tsunami Inundation Modeling for Exchange (TIME) program. Model results have been compared with the observed runup values all along the west coast of Puerto Rico. 相似文献
192.
P. Hofmann A.Y. Huc B. Carpentier P. Schaeffer P. Albrecht B. Kelly J.R. Maxwell J.S.Sinninghe Damst J.W. de Leeuw D. Leythaeuser 《Organic Geochemistry》1993,20(8)
The lower Oligocene evaporite sequence of the Mulhouse Basin (France) contains organic matter-rich marl deposits. These marls display an overall cyclic variation of sedimentation rate, organic carbon content, hydrogen index and selected molecular parameters over a 30 m thick stratigraphic interval. The integration of all sedimentological and geochemical parameters has allowed the reconstruction and characterization of the paleoenvironment of deposition. The marls were deposited in a perennial lake that was at times connected to the sea. Two organic facies end members could be assigned to a lake stage with a marine connection and a lake stage that received dominantly continental water input. The overall stratigraphic variation in the organic matter content is interpreted to reflect the adaptation of the Oligocene flora to the changing paleoclimate and environmental conditions. 相似文献
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194.
Cities are not only major contributors to global climate change but also stand at the forefront of climate change impact. Quantifying and assessing the risk potentially induced by climate change has great significance for cities to undertake positive climate adaptation and risk prevention. However, most of the previous studies focus on global, national or regional dimensions, only a few have attempted to examine climate change risk at an urban scale and even less in the case of a recent literature review. As a result, a quantitative assessment of climate change risk for cities remains highly challenging. To fill this gap, the article makes a critical review of the recent literature on urban-scale climate change risk assessment, and classifies them into four major categories of studies which jointly constitute a stepwise modelling chain from global climate change towards urban-scale risk assessment. On this basis, the study summarizes the updated research progresses and discusses the major challenges to be overcome for the seamless coupling of climate simulation between different scales, the reproduction of compound climate events, the incorporation of non-market and long-lasting impacts and the representation of risk transmission insides or beyond a city. Furthermore, future directions to advance quantitative assessment of urban-scale climate change risk are highlighted, with fresh insights into improving study methodology, enriching knowledge of climate change impact on city, enhancing abundance and accessibility to data, and exploring the best practice to provide city-specific climate risk service. 相似文献
195.
在研究煤田火区对自然-社会经济系统影响的基础上,提出了煤田火区环境影响综合评价指标体系的构建思路,建立了煤田火区环境影响评价的一般性指标体系,包括5级32个指标。以内蒙古乌达煤田火区为实例,论述了煤火环境影响综合评价的实施过程。根据煤田火区特征,在一般指标体系框架内确定了23个评价指标,采用层次分析法与综合指数法相结合,建立了火区环境影响综合评价公式。评价结果表明,乌达煤田火区对环境的影响为较严重水平,与定性分析结果相符。 相似文献
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197.
采用物探和钻探相结合的综合勘察方法,获取地质环境的破坏现状和采空区特征.按相关规范要求,预测小窑采空区的影响范围,剖析采空区残留空洞的稳定性,评价采空区的活化潜在威胁,分析采空引起的覆岩三带发育特征,剖析采空区引起的地表移动特征,获取相应地表变形特征参数. 相似文献
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199.
Risk Assessment,Emergency Preparedness and Response to Hazards: The Case of the 1997 Red River Valley Flood,Canada 总被引:1,自引:0,他引:1
The prevention and/or mitigation offlood disasters requires continual research, numerouscapital investment decisions, and high-qualitymaintenance and modifications of flood-controlstructures. In addition, institutional and privatepreparedness is needed. The experience offlood-control in North America has shown mixedoutcomes: while flood frequency has declined duringthe last few decades, the economic losses havecontinued to rise. Recent catastrophic floods havealso been linked to major structural interventions inthe region. The flood diversions may cause harmfuleffects upon the floodplain inhabitants by influencingflood levels in areas which are not normallyflood-prone. The increasing vulnerability of thefloodplain inhabitants poses new challenges and raisesquestions concerning the existing risk assessmentmethods, institutional preparedness and responses todisaster-related public emergencies, and local-levelpublic involvement in flood mitigation efforts.In the context of the catastrophic 1997 floods of theRed River Valley, Manitoba, Canada, this researchfocuses on two aspects of flood-related emergencygovernance and management: (i) the functions andeffectiveness of control structures, and (ii) theroles, responsibilities and effectiveness oflegislative and other operational measures. The studyconcludes that the flood-loss mitigation measures,both in terms of effects of control structures andinstitutional interventions for emergency evacuation,were not fully effective for ensuring the well-beingand satisfaction of floodplain inhabitants. Althoughorganizational preparedness and mobilization to copewith the 1997 flood emergency was considerable, theirsuccess during the onset of the flood event waslimited. Lack of communication and understandingbetween institutions, a reluctance to implementup-to-date regulations, and minimal publicparticipation in the emergency decision-making processall contributed to the difficulties experienced byfloodplain inhabitants. 相似文献
200.
El Niño-Southern Oscillation: Related Probabilities of Fatalities from Natural Perils in Australia 总被引:1,自引:0,他引:1
The interannual variability of flood, bushfire andheatwave fatality data for eastern Australia duringthe period 1876–1991 was analysed with respect to thephase of the El Niño-Southern Oscillation (ENSO)and the associated values of the Southern OscillationIndex (SOI). Heatwaves were found to be the mostserious peril in terms of the total number offatalities, while floods ranked first in the fatalityevent day statistics. None of the three monthly(absolute value) fatality data sets showed significantcorrelations with the corresponding values of the SOI,while the correlation analysis of annual (July toJune) data led to significant correlation coefficientsof 0.5 for floods and -0.3 for bushfires. AdditionalSOI value-related classification of the standardisedfatality event days into several ENSO categoriesconfirmed the correlation trends by showing anincrease (decrease) in the standardised bushfire(flood) fatality event day frequencies with increasingvalues of the SOI. In contrast to that, thestandardised heatwave fatality data showed aninconclusive distribution pattern, which hints at theinfluence of other possible factors (such as airpollution) on heatwave-related fatality numbers.The results of a risk assessment analysis have shownthat the probability of reaching the mean annualnumber of flood-fatality event days is roughly fourtimes higher during La Niña seasons (80%) thanthe corresponding probability associated with ElNiño periods (18%). The correspondingprobabilities associated with the mean bushfire andheatwave fatality event days displayed a reversedpattern, with the probabilities of El Niño-relatedyears being roughly twice as high as those associatedwith La Niña seasons (70% and 30% for bushfires,and 60% and 25% for heatwaves, respectively).Further probability calculations performed on thetotals of fatalities from all three perils identifiedthe La Niña years as potentially the mostdangerous in terms of suffering fatalities from theseperils. Furthermore, they highlighted the significantdifferences between the means of fatality event daynumbers recorded during years of extreme SOI values(9.8 for La Niña, and 9.1 for El Niño seasons)and those marked by near-zero SOI values (6.6). Themajor reason for the increase in risk associated withextreme ENSO phases was the higher variability ofthese perils during the respective seasons. 相似文献