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1.
渭河上游两次致洪暴雨过程的对比分析   总被引:1,自引:0,他引:1  
对渭河支流上游两次致洪暴雨过程进行了对比分析,结果表明:在泾河上游,两次大暴雨的落区相差在100km以内;两次暴雨过程均给当地和渭河下游造成了严重的洪涝灾害;洪水过程的洪峰特点分别属于缓型洪水和陡型洪水;500hPa天气分型虽然一次为西南气流型,一次为西风槽型,但700hPa的直接影响系统基本相同.物理量诊断对比分析表明:在暴雨出现前12h,低层辐合、高层辐散的垂直结构已基本形成,到暴雨出现临近辐合辐散迅速加强,为暴雨形成和维持提供了非常有利的动力条件.  相似文献   

2.
2005年渭河、汉江流域一次致洪暴雨过程浅析   总被引:4,自引:0,他引:4  
采用了高空、地面常规气象观测资料、水文资料和NCEP格点资料,对2005年出现在渭河、汉江流域一次秋季连阴雨中的致洪暴雨过程进行了分析。结果表明:这次强降水持续时间长,降水总量大,地域集中,洪水汇流快,造成的灾害重;分别是渭河下游、汉江干流1981年和1983年以来的最大洪水过程。渭河洪水有7大特点,汉江洪水有3个明显特点;次致洪暴雨过程的主要影响系统是500 hPa的西风槽、副高、700 hPa及以下的低涡切变;暴雨的水汽主要来自孟加拉湾和南海;动力场上的高层辐散、中低层强辐合,使垂直上升运动强烈发展,为致洪暴雨的形成提供了非常有利的动力条件。  相似文献   

3.
对2000~2003年陕西三场洪灾暴雨天气的对比分析   总被引:4,自引:2,他引:4  
段桂兰  陶建玲 《灾害学》2004,19(Z1):24-28
对陕西2000年7月13日紫阳和镇巴暴雨、2002年6月8日佛坪暴雨及2003年8月23日~10月4日渭河流域(二华夹槽地区)的连阴雨中的暴雨从环流形势场进行了对比分析,认为,在不同天气气候背景下都有可能出现大的洪涝灾害,只有提高防范意识,才可以减轻灾难造成的结果.  相似文献   

4.
淮河流域致洪暴雨特征及预警指标分析   总被引:1,自引:0,他引:1  
张爱民  谢重阳 《灾害学》2005,20(1):50-52
本文通过对1950~2000年的个例分析,总结了淮河流域致洪暴雨的天气学特征和判别指标;根据区域降水量与王家坝站的水位分析,确定了淮河流域致洪暴雨的预警指标.  相似文献   

5.
渭河流域洪水灾害特征分析   总被引:17,自引:8,他引:17  
分析了新中国成立以来渭河流域45次洪水灾害过程的年际变化、渭河不同河段及干支流洪水灾害特征;同时通过对致洪暴雨的时空分布、类型及灾害的分析,总结了导致渭河流域洪水灾害的降水特征。  相似文献   

6.
利用淮河流域内稠密的区域自动站资料、多普勒天气雷达组网资料、风云二号卫星双星观测资料及LAPS中尺度分析资料,对2007年7月8日淮河流域大暴雨过程的中尺度特征进行了综合分析,得出了一些有意义的结果.(1)这次降雨过程集中在淮河干流,呈现出强降水区稳定少动,高雨强出现频度大的特点,时空分布有利于形成大洪水,是一次典型的致洪大暴雨过程.(2)暴雨区与中低层的中尺度辐合扰动的形成、发展与移动密切相关,同时伴随着中尺度云团、雨团的强烈发展.中尺度雨带具有准静止性,且强度很强,这是此次暴雨过程的一个突出特点.(3)强降雨主要是在α尺度云带上不断生消发展的β中尺度云团,甚至更小的y中尺度云团的生消合并造成的.它们大多生消于32~34°N、114~118°E范围内,β中尺度对流云团的生消、演变和移动与中β尺度雨团的强度和位置有较好的对应关系,强降水发生在中尺度对流云团合并发展和增强阶段.(4)暴雨区具有低层辐合高层辐散、高湿、正涡度和强烈上升运动的特征,它们加强中低层的动力抬升,促使斜压不稳定能量释放,引起垂直涡度的发展,产生很强的降水.强降雨发生时,对流层中层的比湿快速加大,而云中液态水则表现为骤然减小.  相似文献   

7.
介绍了一种基于致洪暴雨预报,结合水文控制站水位、流量信息,运用多元统计回归模型开展的三峡水库洪水程度分级预估的方法.通过历史回代和2010、2011年预估试验应用表明:该预估系统稳定可靠,适用于三峡水库洪水程度预估,对三峡上游暴雨引发的洪水程度能进行准确的预估,而且对三峡上游支流的暴雨洪水预测也有一定的预见性.应用该系统三峡水库的洪水预见期可达3d以上,能为防汛决策和三峡水库防洪调度赢得时间.  相似文献   

8.
利用2005年9~10月渭河流域内各气象站和水文站的资料,对2005年渭河流域致洪暴雨的雨情、水情及灾情进行分析。对洪水的特征,水情、河道的概况,特大洪灾的降水特点进行总结,得出“05.10”洪水具有降水范围广、水位高、洪水倒灌、灾害重等特征,造成的经济损失严重。揭示了洪灾形成的主要原因,从而对减少洪灾的形成和流域的治理提出有关建议,达到防灾减灾的目的。  相似文献   

9.
利用常规气象观测资料、NCEP再分析资料对2016年8月21日傍晚到夜间贺兰山沿山特大致洪极值暴雨展开研究,分析了异常大气环流形势及其影响,并利用天气研究和预报模式WRF(Weather Research and Forecasting model)进行数值模拟和地形敏感性试验,研究了贺兰山地形对暴雨过程的影响。结果表明:超强厄尔尼诺结束后的盛夏,大气环流形势发展异常,8月南亚高压和副热带高压异常偏强,西北地区东部处于高温、高湿、高能控制,副高的快速进退和冷平流的入侵,触发暖湿不稳定能量强烈聚集与快速释放,导致特大暴雨的爆发。其发生在200hPa高空急流分流区即强辐散区、中空西南气流的高温高湿区、低空偏南急流轴左侧流场最大弯曲处的强暖平流区、850hPa偏东大风速轴南侧的风速辐合区,天气尺度强迫作用相对较弱的环境中,500hPa短波槽与700hPa、850hPa低涡切变线和偏南偏东急流以及地面气旋式切变辐合线共同作用是其发生的主要影响系统。贺兰山地形对特大暴雨的发生有明显的增幅效应,主要是贺兰山地形阻挡与强迫抬升作用,促使低涡切变强烈发展从而影响了降水范围、强降水落区及其中心位置等。  相似文献   

10.
张思豆  张杰  曹杰 《灾害学》2018,(4):204-210
采用三重嵌套网格,利用NCEP的1°×1°再分析资料以及新一代中尺度预报模式WRF模式,对2014年6月6日08:00-7日08:00川滇切变线致灾暴雨过程进行了数值模拟实验,并对结果进行诊断分析。结果表明:WRF模式可以较为客观地模拟出暴雨过程的落区和强度,较好地反映了强降水过程的实况和基本特征,模式能很好地指示出强降水发生的高湿水汽条件以及正涡度发展、强烈上升运动和下正上负垂直螺旋度结构的动力条件,模拟的上升运动位置及700 hPa正涡度带和正垂直螺旋带亦对强降水落区有很好的指示性,另外除了模拟的切变线位置稍偏西偏南而导致暴雨区稍偏西偏南外,对高低层影响系统的走向、结构、位置和强度的模拟结果与实际结果相近,表明该模式对云南省切变线致灾暴雨系统具有较好的模拟效果。  相似文献   

11.
Malholland K 《Disasters》1985,9(4):247-258
In 1985 cholera has been a serious problem in the horn of Africa, particularly affecting the many famine victims and refugees in that region. In this paper the history of cholera in Africa is briefly summarized, as is the background to the current refugee situation in eastern Sudan. A cholera epidemic involving 1,175 cases in two adjacent refugee camps in eastern Sudan is described. In this epidemic there were thirteen inpatient deaths and thirty-eight known home deaths from cholera. The management of the epidemic is described in detail. Overall an average of 8 1. of intravenous fluid was used per case, a higher figure than was anticipated, probably because of the unexpected degree of vomiting and the shortage of trained nursing staff.
The relationship between cholera and malnutrition is explored and hypochlorhydria is suggested as the main reason for the increased susceptibility to cholera among malnourished populations. It was observed that severely malnourished adults and children appeared to nave less severe diarrhoea with their cholera, presumably because of reduced mucosal surface area and poor enterocyte function. Finally possible means of aborting cholera epidemics are discussed.  相似文献   

12.
The land borders of Evros, Greece, have been a common entry point for undocumented migrants on their way to Europe through Turkey. Adverse conditions, however, have resulted in many human casualties over the years. On the Greek side, 334 cadavers were retrieved between 2000 and 2014. This study provides a detailed forensic account of the humanitarian disaster in Evros to create an official scientific record of the situation. It showcases the gravity of the global issue of migration relating to health and mortality, and encourages communication and continual improvement of the approach and patterns of practices surrounding the subject. A retrospective statistical research review was conducted of border‐related fatalities between 2000 and 2014, assessing the age and gender of victims, the cause of death, the location of bodies, identification rates, and country of origin. Age ranged generally from 24 to 29 years, but infants and children were among the deceased.  相似文献   

13.
Helen Young  Musa Adam Ismail 《Disasters》2019,43(Z3):S318-S344
Darfur farming and pastoralist livelihoods are both adaptations to the environmental variability that characterises the region. This article describes this adaptation and the longer‐term transformation of these specialised livelihoods from the perspective of local communities. Over several decades farmers and herders have experienced a continuous stream of climate, conflict and other shocks, which, combined with wider processes of change, have transformed livelihoods and undermined livelihood institutions. Their well‐rehearsed specialist strategies are now combined with new strategies to cope. These responses help people get by in the short term but risk antagonising not only their specialist strategies but also those of others. A combination of factors has undermined the former integration between farming and pastoralism and their livelihood institutions. Efforts to build resilience in similar contexts must take a long‐term view of livelihood adaptation as a specialisation, and consider the implications of new strategies for the continuity and integration of livelihood specialisations.  相似文献   

14.
Ian Davis 《Disasters》2019,43(Z1):S61-S82
This reflection, based on a keynote address to celebrate the fortieth anniversary of Disasters on 14 September 2017, begins by considering some of the prevailing assumptions that existed at the time of the journal's creation. Next is a summary of significant milestones during the past 40 years, covering major global trends, changing disaster impacts, and key developments in disaster risk management. Contrasting approaches in the first and fourth decade of the journal's history are then followed by examples of changes in terminology in the disaster field as an indication of shifting values. The paper goes on to explore the context of 2017, with observations of problem areas such as the loss of knowledge, failures to tackle the root causes of disasters, shortfalls in international assistance, and some negative attitudes. It closes by evaluating some current positive occurrences, including a reduction in casualties, sharing of experience, technological advances, and dramatic improvements in disaster warning.  相似文献   

15.
Joseph Chung 《Disasters》1987,11(1):40-48
Tropical cyclones and hurricanes have a severe impact on the social and economic activities of affected communities. For small island nations in the Pacific region, the effects can be devastating because of their smallness. FQi and several other countries in the region are vulnerable to such disasters as they are situated in the zone where cyclones occur frequently.
During the last decade, the frequency of natural disasters and their adverse impact on die economic and social development of small nations like Fiji, has aroused awareness mat relief efforts must go beyond immediate "mopping up" operations to those which contribute to attaining longer term benefits through reconstruction and rehabilitation.
The paper outlines the 1985 agricultural rehabilitation program and discusses related issues and problems.  相似文献   

16.
Steckley M  Doberstein B 《Disasters》2011,35(3):465-487
This paper presents the results of primary research with 40 survivors of the 2004 Indian Ocean tsunami in two communities: Khao Lak (n=20) and Koh Phi Phi Don (n=20), Thailand. It traces tsunami survivors' perceptions of vulnerability, determines whether residents felt that the tsunami affected different communities differently, identifies the populations and sub-community groups that survivors distinguished as being more vulnerable than others, highlights community-generated ideas about vulnerability reduction, and pinpoints a range of additional vulnerability reduction actions. Tsunami survivors most consistently identified the 'most vulnerable' community sub-populations as women, children, the elderly, foreigners, and the poor. In Khao Lak, however, respondents added 'Burmese migrants' to this list, whereas in Koh Phi Phi Don, they added 'Thai Muslims'. Results suggest that the two case study communities, both small, coastal, tourism-dominated communities no more than 100 kilometres apart, have differing vulnerable sub-groups and environmental vulnerabilities, requiring different post-disaster vulnerability reduction efforts.  相似文献   

17.
建筑物在火场中的结构响应问题中,门窗玻璃在火场中的热响应特性及破裂脱落是影响火灾发展的重要因素之一。通过事故案例分析了火灾场景中玻璃破裂脱落的危害性,指出了研究火灾场景中玻璃受热破裂脱落的意义,并对目前火灾场景中玻璃受热破裂过程和主要形态、玻璃的破裂机理和判据等的研究现状进行了详细的分析,总结了目前实验和计算机模拟的最新研究进展和不足,为今后进一步开展玻璃受热破裂脱落研究提出了若干建议。  相似文献   

18.
中国内陆自然环境的干旱化与未来趋势   总被引:5,自引:2,他引:3  
延军平 《灾害学》1999,14(2):28-32
根据中国内陆陕西、甘肃部分地区509a旱涝资料和主要测站气象、水文实测数据,应用Word97图形处理系统,证明在526a序列中目前处在11a、50a滑动的干旱期。近46a气温上升了0.3℃,年降水减少了80mm,径流量减少了0.78%,出现了明显的干旱化,环境变化趋势不容乐观。  相似文献   

19.
朱绛 《灾害学》2002,17(4):83-86
美国开展洪泛平原管理已有约40年历史,洪水保险计划是美国泛平原管理的主要措施。了解并借鉴他们的思路与具体策略,将有助于我国洪泛平原管理政策的制定。  相似文献   

20.
Young L 《Disasters》1985,9(2):122-133
This paper attempts to examine the broad features of Somalia's harsh physical environment into which several hundreds of thousands of refugees, with mainly a nomadic or semi-nomadic life style and culture, dramatically descended six years ago. The thirty-six rural camps in which at least half of them live are described as is the refugee agricultural programme which is training several thousand families so that they may be "self-supporting." The four regions where the camps are located are each briefly summarized in terms of their soils, their climates, their natural vegetation, and the type of agriculture which the refugee farmers practice. A more detailed analysis is then given on the following critical environmental concerns: Vegetation and erosion on refugee farms, the growing problem of refugee livestock, the destruction of trees, and irrigation practices and salinity on refugee farms. The paper concludes with an argument to preserve Somalia's environment from careless and destructive exploitation, which is leading towards desertification, and calls for an in-depth study of the situation.  相似文献   

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