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1.
云南春末夏初干旱的气候特征   总被引:7,自引:0,他引:7  
利用云南124个测站1961-2005年4-5月的月降水量及气温资料,采用EOF方法及离散功率谱方法,分析了云南4-5月的降水总量及平均气温的时空变化特征及其变化周期,得到了如下结论:(1)降水场与温度场具有相似的空间分布特征,全省一致性分布型.这种分布型存在明显的年际变化特征,500hPa环流差异明显.(2)全省平均降水量与平均温度具有明显的年际变化特征.1963年是近45年中的降水最少年,2004年则是降水最多年.1969年是近45年平均气温最高年,1990年则是气温最低年.(3)全省平均降水量与平均温度也具有明显的年代际变化特征.20世纪60和90年代高温低湿;70和80年代低温高湿;2001年以后转入高温高湿.2005年春末夏初的干旱就是发生在高温高湿气候背景下的较为异常的气候事件.(4)降水量存在明显的2~3年左右的年际变化周期,同时也存在明显的15年的年代际变化周期.平均气温2~5年左右的年际变化较为明显,而较长时间的年代际变化周期较弱.  相似文献   

2.
基于SPEI的华北地区近50年干旱发生强度的特征及成因分析   总被引:3,自引:0,他引:3  
基于华北地区67个气象站1962-2011年的实测资料,利用标准化降水蒸散指数(SPEI),统计了近50 a各站点出现的干旱过程,探讨了华北地区干旱发生强度的时空分布特征和中度以上干旱的空间分布特征,并对干旱成因进行了分析。结果表明,近50 a来华北地区干旱发生强度呈明显的增强趋势,尤其是在20世纪80、90年代;华北地区干旱发生强度的整体特征是西北和东南部地区较强,东北和中西部地区较弱;造成华北干旱的最主要因素是降水量的起伏变化,这在20世纪80,90年代表现得特别显著。  相似文献   

3.
干旱指标及其在新疆阿勒泰地区干旱监测分析中的应用   总被引:2,自引:0,他引:2  
干旱是限制新疆阿勒泰地区农牧业生产可持续发展最主要的自然灾害之一,研究适合该区的干旱指标,是进行有效干旱监测的基础。采用新疆阿勒泰地区7个气象站1961-2008年4-10月月平均气温、降水量资料,首先通过Thomthwaite方法计算潜在蒸发量确定K干旱指数,然后对R指数、Z指数、K指数3种干旱指标进行了分析,结果表明,在监测诊断干旱轻重程度上,K指数能较客观地反映出干旱程度,R指数和Z指数监测干旱程度较轻。在此基础上,基于K指数建立的阿勒泰地区干旱监测评价的强度指数和面积指数,对该地区近48年来干旱的变化进行了分析,表明该地区干旱灾害主要集中在春夏季节,春夏连旱几率较高,强度较大;该地区干旱灾害具有阶段性特征,近年来干旱发生的频次有增多的趋势,其中秋季干旱相对较为明显。  相似文献   

4.
于文金  苏荣  谢涛 《灾害学》2016,(4):17-21,53
当前全球变暖趋势愈发明显,极端天气出现的概率以及强度都不断提升。诸多极端天气都影响了沿海地区的发展。以河北秦皇岛港口为例,采用综合干旱指数、EMD分解、回归分析等方法,探讨秦皇岛港区的极端天气灾害特征及其对港口锚地的影响。研究结果表明:1秦皇岛港区历年干旱发生频率约为48%,春季干旱发生频率在45%左右,四季中春旱发生频率最高。近60年以来,秦皇岛港区的干旱持续时间和干旱强度虽存在明显的年际波动,但线性变化趋势不明显。2秦皇岛港区年降水量总体来说振幅逐渐变小,而平均周期由短变长。暴雨序列与年降水量序列周期对应关系较好,准6年周期是秦皇岛港区暴雨灾害的主周期。3极端天气因子中高温天数、年均降水量以及大雨天数为主要影响因子,会影响秦皇岛港货物吞吐量,且均与吞吐量呈负相关。  相似文献   

5.
东北地区干旱强度频率分布特征及其环流背景   总被引:9,自引:0,他引:9  
考虑到气候变暖对干旱加剧的可能影响,利用1951-2007年中国东北地区17站的月降水量和气温资料,定义了表征该地区各站干旱强度的指数.在此基础上分析了干旱强度的周期变化和频率分布特征,以及夏季干旱强度变化与同期水汽输送异常的联系.结果表明,东北地区干旱强度变化具有显著的2~3年的周期变化.近57年来东北地区的干旱变化经历了4个气候阶段,近期的1996-2007年是近57年来干旱发生频次最多的时期,平均每年有4.1月会出现不同程度的干旱,发生干旱的频率为34%.东北地区夏季发生干旱的频率最高,达34.5%, 春季次之,为32.25%, 秋季为27.5%, 冬季发生干旱的频率最小.夏季蒙古高压增强,副热带高压偏弱,位置偏南,同时西风带水汽输送和孟加拉湾西南水汽输送异常减弱,是导致东北地区夏季发生干旱的主要环流背景.  相似文献   

6.
青海省东部农业区作物生长期不同气象干旱指标应用研究   总被引:2,自引:0,他引:2  
干旱一直是制约青海东部农业区农牧业生产最主要的气象灾害。利用青海东部12个气象站点近46年(1961-2006年)的气象资料,计算标准化降水指数(SPI)、降水Z指数和相对湿润度指数(M),并对各干旱指标表征的年、春季和夏季的干旱强度和干旱频率与实际干旱事件进行对比,分析其在研究区的适用性,进而分析研究区的干旱变化特征。结果表明:3种干旱指标相比,相对湿润度指数(M)对实际干旱事件的反映更准确,且能反映出不同地区干旱发生频率的差异。选取相对湿润度指数(M)作为区域干旱监测指标,得出时间上区域的春季干旱强度年干旱强度夏季干旱强度,夏季的干旱强度有不显著的增大趋势,而年尺度和春季的干旱强度有不显著的减小趋势;空间上,区域干旱频率和干旱强度均表现为南高北低的特征。  相似文献   

7.
华北异常干旱气候事件及其对农业影响评估模式的研究   总被引:8,自引:0,他引:8  
李翠金 《灾害学》1999,14(1):65-69
分析了华北地区旱灾的特点;采用降水量距平百分率和干旱指数分别确定了单站及区域于旱等级标准,并对近37a这一地区各年主要干旱事件强度(等级)进行了评定,最后建立了干旱受灾面积和成灾面积评估模式。  相似文献   

8.
利用吉林省1961-2015年46个气象站的逐日气象数据,结合Penman-Monteith方程,计算玉米生育期逐旬需水量(Et_c)、降水量以及作物水分亏缺指数(CWDI),根据干旱等级指标计算逐旬不同等级干旱频率、平均干旱强度以及干旱风险指数,并分析其空间分布和时间变化特征。结果表明:从玉米生长季水分供需状况看,西部地区整个玉米生长季水分亏缺最严重,玉米易遭受干旱威胁,中部发生干旱的威胁次于西部地区,东部发生干旱的威胁最小。西部地区干旱发生频率最高,其次是中部,东部地区干旱发生频率最低,平均干旱强度和干旱风险指数与此有相同的分布特征。各等级干旱基本上是在玉米生长的前期和后期发生频率较高,而在玉米生长的关键期,发生频率相对较小。除个别情况,各时段基本是轻旱发生频率最高,其次是中旱,而重旱发生频率较低,特旱发生频率最低。代表站各时段水分亏缺指数年际变化基本是中前期呈减少趋势,中后期呈增加趋势。不同时段各等级风险区空间分布也存在差异。  相似文献   

9.
云南滑坡泥石流灾害及其与降水特征的关系   总被引:9,自引:0,他引:9  
利用2001-2005年云南滑坡泥石流灾害资料,分析了近5年来云南滑坡泥石流分布与演变的特点及其与云南降水、大雨、暴雨之间的关系.研究结果表明,在该时段云南滑坡泥石流灾害总体分布表现出西多东少,西北多东南少的趋势;滑坡泥石流灾害高发区与暴雨中心有很好的对应关系,其活动存在明显的年际变化特点,并且各个区域又有自身的演变规律.在时空分布上滇西北及滇西南是活动最频繁的区域;滑坡泥石流灾害具有明显的月际变化特征,高峰期集中在6-8月;滑坡泥石流灾害发生次数与年降水量、年暴雨次数及年大雨次数有着很好的对应关系;大气环流异常对滑坡泥石流灾害发生数量也有着明显的影响.  相似文献   

10.
收集整理了近几十年华北地区逐日降水(1961-2012年)和铁路水害资料(1973-2012年),采用了趋势分析、相关分析等多种统计方法分析了华北地区汛期降水特性及其与铁路水害的关系,并提出了应对这一铁路水害的防御措施。结果表明,华北地区夏季各等级降水量和降水日数均呈现出显著下降趋势,其中暴雨量和小雨日数的下降趋势最为显著。各等级降水强度变化趋势不同,小雨和大雨强度呈上升趋势。华北夏季持续性强降水过程的发生次数、持续天数及过程降水量均有减少趋势,并呈现一致的年代际特征。7月持续性强降水过程出现次数最多,其次为8月。2000年以来,6月发生持续性强降水过程的次数明显增多。华北铁路水害断道时间和次数均呈下降趋势。  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.
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   

15.
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   

16.
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   

17.
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   

18.
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   

19.
30年来我国农业气象灾害变化趋势和分布特征   总被引:7,自引:0,他引:7  
利用1979-2008年的统计数据分析了我国近30年来农业气象灾害的时间变化趋势和空间分布特征。结果表明:(1)1979-2008期间,我国农业气象灾害的灾情日趋严重,农业气象灾害总成灾面积和成灾比率都呈增加趋势;各类灾害中,旱灾和霜冻成灾面积和成灾比率呈增加趋势,风雹成灾面积和成灾比率变化不大呈略微下降趋势,而1989-1998年段水灾严重。(2)旱灾成灾面积在总成灾面积中所占比例最大(约占总成灾面积的1/2),其次是水灾(约占总成灾面积的1/4),再次是风雹,而霜冻成灾面积最小。(3)在区域分布方面,旱灾灾情华北地区最为严重,其次是东北,再次是西北;水灾和旱灾的轻重程度往往是一个此消彼长的关系,华中的水灾最严重,其次为华东、华南和西南;风雹灾情的轻重程度在我国的分布也有较强的区域性,华北、西北和东北是风雹的重灾区;霜冻分布各区域差异较小,西北和华中的灾情相对较重。  相似文献   

20.
Willibald S 《Disasters》2006,30(3):316-339
This paper analyses the relevance and potential of cash transfers as part of the disarmament, demobilisation and reintegration (DDR) assistance packages provided to ex-combatants in transitions from war to peace. To this end, a theoretical framework is established that permits the identification of the advantages and disadvantages of using cash in DDR. Subsequently, an empirical analysis is carried out to compare selected theoretical assumptions on the use of cash with the reality of lessons learned from recent experience in Sierra Leone and other African countries. The study shows that some theoretical drawbacks commonly associated with the use of cash in DDR processes may indeed bear out in practice. At the same time, though, the paper argues that the utility of cash transfers in DDR is affected by a variety of factors that go far beyond the simple choice of employing cash, most notably decisions on payment location, eligibility criteria and targeting.  相似文献   

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