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柳江致洪暴雨及其影响系统统计特征分析 总被引：2，自引：0，他引：2
通过对柳江流域历年25个致洪暴雨过程进行统计分析，发现柳江流域致洪暴雨主要发生于6～7月，20世纪90年代后柳江致洪暴雨的发生频率和强度都有增加的趋势，柳江东北部流域和西部流域是柳江洪水的主要来源地，分析还发现柳江致洪暴雨的主要影响系统有高空槽（南支槽）、低涡、低层切变线、地面静止锋、低空急流、副热带高压等6种，可分为低槽切变类、低涡切变类和低空急流切变类三种类型。 相似文献
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通过对柳江流域历年25个致洪暴雨过程进行统计分析，发现柳江流域致洪暴雨主要发生于6～7月，20世纪90年代后柳江致洪暴雨的发生频率和强度都有增加的趋势，柳江东北部流域和西部流域是柳江洪水的主要来源地，分析还发现柳江致洪暴雨韵主要影响系统有高空槽（南支槽）、低涡、低层切变线、地面静止锋、低空急流、副热带高压等6种，可分为低槽切变类、低涡切变类和低空急流切变类三种类型。 相似文献
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对１９８８～１９９７共１０ａ的柳江致洪暴雨过程进行了分析,从中总结出引起柳江特大洪峰暴雨的若干结论及可行性预报方法。 相似文献
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利用非静力中尺度数值模式MM5V36对2004年7月21日广西柳江流域致洪暴雨过程进行数值模拟并对几种数值预报产品进行分析,结果表明,MM5V36模式对这次过程具有较强的模拟能力,数值预报产品能为防汛抗洪决策服务提供有力的参考依据. 相似文献
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利用非静力中尺度数值模式MM5736对2004年7月21日广西柳江流域致洪暴雨过程进行数值模拟并对几种数值预报产品进行分析，结果表明，MM5736模式对这次过程具有较强的模拟能力，数值预报产品能为防汛抗洪决策服务提供有力的参考依据。 相似文献
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一次华南西部低涡切变特大暴雨的中尺度特征分析 总被引：9，自引：1，他引：8
利用常规观测资料、卫星云图、雷达回波反演资料、自动气象站降水量以及NCEP/NCAR再分析资料,对2007年6月12—13日发生在华南西部的一次低涡切变特大暴雨过程的中尺度特征进行了分析,结果表明:(1)500 hPa高空槽经向度加大并东移南压,中低层低涡沿切变线东移,低空西南急流建立以及地面浅薄冷空气活动等天气系统相互作用触发了中尺度对流系统(MCS)的发展,造成暴雨。(2)地面降水时空分布具有明显的中尺度特征。大暴雨中心水平尺度都小于200 km,雨团持续时间5—7 h。(3)特大暴雨中心主要是由MCS移入造成的。柳江特大暴雨中心由两个MCS产生,一个沿低涡切变南侧的偏南气流移到暴雨中心上空;另一个沿切变线东移到暴雨中心上空。沿海暴雨中心则由一个MCS发展引发的。降水主要出现在MCS的中部冷云区内或云团边缘TBB梯度最大处。与MCS的生消过程对应,柳江暴雨区包含两次中尺度降水过程,第1次降水以热对流云团造成为主,第2次降水以低涡云系激发的MβCS产生强降雨为主;而沿海暴雨区是1次短时间持续性的MβCS强降水产生。暴雨主要由不断发展旺盛的对流单体引起,暴雨发生伴随着低空西南急流的建立,2—3 km高度上低空急流风速脉动增强了MCS的发展。(4)暴雨发生在高相当位温舌中,湿层厚度超过400 hPa,暴雨区层结具有位势不稳定或中性层结。(5)中尺度对流系统具有深厚的垂直环流结构,低层涡度柱在暴雨发生过程明显抬升,增强低层水汽辐合,锋区的动力强迫上升运动加强低层能量和水汽的往上输送,高层辐散气流增强MCS的发展。同时,暴雨区地形的作用增强了锋面强迫上升运动。 相似文献
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一九八三年,我区出现了两次罕见的全区性的大暴雨过程,一次发生在冬季1月3-7日,另一次发生在夏季6月18-22日。1月那一次是解放以来没有过的,雨强偏大,共有35个站下了暴雨,其中桂东南下了大暴雨,部分县出现了冬涝。6月那一次据说是百年不遇的,有26个县连续出现了大雨暴雨或特大暴雨,其中融水、融安、资源、环江、凤山等五个县的降水量达到三百七十至七百毫米,致使融江、柳江、桂江、西江水位陡涨,河水泛滥,灾及桂林、河池、柳州、梧州、百色五个地区的49个县和柳州、梧州两个市,使生命财产、工农业生产和交 相似文献
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J. Rolf Olsen 《Climatic change》2006,76(3-4):407-426
Federal agencies use flood frequency estimates to delineate flood risk, manage the National Flood Insurance Program, and ensure that Federal programs are economically efficient. The assumption behind traditional flood risk analysis is that climate is stationary, but anthropogenic climate change and better knowledge of interdecadal climate variability challenge the validity of the assumption. This paper reviews several alternative statistical models for flood risk estimation that do not assume climate stationarity. Some models require subjective judgement or presuppose an understanding of the causes of the underlying non-stationarity, which is problematic given our current knowledge of the interaction of climate and floods. Although currently out of favor, hydrometeorological models have been used for engineering design as alternatives to statistical models and could be adapted to different climate conditions. Floodplain managers should recognize the potentially greater uncertainty in flood risk estimation due to climate change and variability and try to incorporate the uncertainties into floodplain management decision-making and regulation. 相似文献
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本文分析了近500年黄河流域旱涝的演变特征，并且利用几个较著名的全球三维环流模式的模拟结果分析了各种物理因子对华北地区旱涝影响的大小，同时利用观测资料亦分析了这些物理因子与黄河流域旱涝的相关。 相似文献
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Coastal areas around the world are urbanizing rapidly, despite the threat of sea level rise and intensifying floods. Such development places an increasing number of people and capital at risk, which calls for public flood management as well as household level adaptation measures that reduce social vulnerability to flooding and climate change. This study explores several private adaptation responses to flood risk, that are driven by various behavioral triggers. We conduct a survey among households in hazard-prone areas in eight coastal states in the USA, of which, some have recently experienced major flooding. While numerous empirical studies have investigated household-level flood damage mitigation, little attention has been given to examining the decision to retreat from flood zones. We examine what behavioral motives drive the choices for flood damage mitigation and relocation separately among property buyers and sellers. Hence, we focus on the drivers that shape demand for future development in flood-prone cities. We find that households’ choices to retreat from or to avoid flood zones (1) are highly sensitive to information that provokes people's feelings of fear, and (2) rely on hazardous events to trigger a protective action, which ideally would take place well before these events occur. We highlight that major flooding may cause a potential risk of large-scale outmigration and demographic changes in flood-prone areas, putting more low-income households at risk. Therefore, coordinated policies that integrate bottom-up drivers of individual climate adaptation are needed to increase urban resilience to floods. 相似文献
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Rüdiger Glaser Dirk Riemann Johannes Schönbein Mariano Barriendos Rudolf Brázdil Chiara Bertolin Dario Camuffo Mathias Deutsch Petr Dobrovolný Aryan van Engelen Silvia Enzi Monika Halíčková Sebastian J. Koenig Oldřich Kotyza Danuta Limanówka Jarmila Macková Mirca Sghedoni Brice Martin Iso Himmelsbach 《Climatic change》2010,101(1-2):235-256
The paper presents a qualitative and quantitative analysis of flood variability and forcing of major European rivers since AD 1500. We compile and investigate flood reconstructions which are based on documentary evidence for twelve Central European rivers and for eight Mediterranean rivers. Flood variability and underlying climatological causes are reconstructed by using hermeneutic approaches including critical source analysis and by applying a semi-quantitative classification scheme. The paper describes the driving climatic causes, seasonality and variability of observed flood events within the different river catchments covering the European mainland. Historical flood data are presented and recent research in the field of historical flood reconstructions is highlighted. Additionally, the character of the different flood series is discussed. A comparison of the historical flood seasonality in relation to modern distribution is given and aspects of the spatial coherence are presented. The comparative analysis points to the fact that the number of flood events is predominately triggered by regional climatic forcing, with at most only minor influence on neighbouring catchments. The only exceptions are extreme, supra-regional climatic events and conditions such as anomalous cold winters, similar to that of 1784, which affected large parts of Europe and triggered flood events in several catchments as a result of ice-break at the beginning of the annual thaw. Four periods of increased occurrence of flooding, mostly affecting Central European Rivers, have been identified; 1540–1600, 1640–1700, 1730–1790, 1790–1840. The reconstruction, compilation and analysis of European-wide flood data over the last five centuries reveal the complexity of the underlying climatological causes and the high variability of flood events in temporal and spatial dimension. 相似文献
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对Z指数确定的旱涝等级及各站月降水距平百分率的标准差分析表明:长江中游地区大范围的旱涝主要集中在盛夏和秋季。不同季节, 旱涝的主要分布区域不同, 但洞庭湖区始终是一个旱涝多发地。对1960年1月—2001年12月各月长江中游地区50个代表站的旱涝等级进行经验正交函数分析, 并在此基础上进行多通道奇异谱分析, 得到长江中游地区的旱涝分布主要存在4种空间型, 且具有明显的年代际和年际尺度变化, 在20世纪80年代以前, 长江中游地区以偏旱型为主, 而到80年代以后则转变以偏涝型为主; 另外, 长江中游地区的旱涝具有准8年、准5年、准2年和准4年的周期振荡性质, 但从80年代初开始, 旱涝的准2年周期特征在长江中游地区表现不再明显。 相似文献
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据1991年特大洪涝过程的物理分析试论江淮梅雨预测 总被引：8，自引：0，他引：8
本文以１９９１年江淮梅雨为个例,通过对特大洪涝形成过程的物理分析,就梅雨预测问题提出了一些认识。分析表明,１９９１年江淮流域较长梅雨期内所发生的３场大暴雨是很有代表性的,它们是大气环流季节转变不同进程中的产物,因而具有不同的环流背景和降水性质,且在洪涝的形成中起着不同的作用。据此,我们提出了江淮梅雨的３个模型,指出应在由春夏之交到盛夏这个较长时期内分阶段地考虑梅雨预测。另外还指出,确定雨带的落区,不但应强调副高和东南季风活动对雨带南北进退的作用,而且也要注意西南季风的活动会导致雨带东西向的摆动。最后,就旱涝形成物理过程的诊断研究在旱涝模式预测方法中的意义作了讨论 相似文献
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山东区域汛期旱涝预测概论 总被引：3，自引：1，他引：3
对1951－2000年期间汛期（6－8月）山东区域旱涝与全国主要多雨带的8个分布类型的逐年对应关系进行了具体的对比和论述。并对烟台、青岛、潍坊、济南、临沂、菏泽等6个地区汛期旱涝的天文、海洋、大气环流和气象要素等方面的预报物理因子进行了全面的普查、筛选、精选和综合分析，并分别建立了汛期降水量预报物理方程。并以青岛地区为例，对汛期降水理的多种交叉学科的预报物理因子进行了最优集成，为青岛地区和水量和旱涝建立了分多级的可操作的预报物理模型。该文优选出来的汛期降水的多学科物理因子对短期气候预测有重要的学术意义，其中所建立的预报物理方程和预报物理模型对山东省各区汛期旱涝的季度和年度预报有重要的应用价值。 相似文献
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Jochen Hinkel Detlef P. van Vuuren Robert J. Nicholls Richard J. T. Klein 《Climatic change》2013,117(4):783-794
This paper studies the effects of mitigation and adaptation on coastal flood impacts. We focus on a scenario that stabilizes concentrations at 450 ppm-CO2-eq leading to 42 cm of global mean sea-level rise in 1995–2100 (GMSLR) and an unmitigated one leading to 63 cm of GMSLR. We also consider sensitivity scenarios reflecting increased tropical cyclone activity and a GMSLR of 126 cm. The only adaptation considered is upgrading and maintaining dikes. Under the unmitigated scenario and without adaptation, the number of people flooded reaches 168 million per year in 2100. Mitigation reduces this number by factor 1.4, adaptation by factor 461 and both options together by factor 540. The global annual flood cost (including dike upgrade cost, maintenance cost and residual damage cost) reaches US$ 210 billion per year in 2100 under the unmitigated scenario without adaptation. Mitigation reduces this number by factor 1.3, adaptation by factor 5.2 and both options together by factor 7.8. When assuming adaptation, the global annual flood cost relative to GDP falls throughout the century from about 0.06 % to 0.01–0.03 % under all scenarios including the sensitivity ones. From this perspective, adaptation to coastal flood impacts is meaningful to be widely applied irrespective of the level of mitigation. From the perspective of a some less-wealthy and small island countries, however, annual flood cost can amount to several percent of national GDP and mitigation can lower these costs significantly. We conclude that adaptation and mitigation are complimentary policies in coastal areas. 相似文献
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近56a武汉市降水气候变化特征分析 总被引：7，自引：1，他引：6
以武汉市1951—2006年逐日降水资料为基础,采用累积距平、线性趋势、移动T检验、5％分位数、小波分析等方法,分析了近56a来武汉市降水气候变化特征。结果表明：（1）近56年来,武汉市年降水量、降水强度呈增加趋势,而降水日数呈减少趋势;（2）除春季外,其它季节以及汛期、梅雨期、伏旱期等时段的降水量均有所增加;降水日数在春、秋季、汛期呈下降趋势,其余时段则为增加趋势;降水强度在夏季、伏早期呈减小趋势,其余时段均为增大趋势;（3）梅雨期、年的降水量变化较为一致,其周期性变化明显,主要表现为10a年代际周期,突变点约在1979年;（4）1960、1970年代暴雨日数较少,在1979年前后突变增多后,进人多暴雨阶段;（5）历年最大日降水量、5％分位数极端降水强度、暴雨平均强度变化略有减少趋势但不显著,而大暴雨平均强度减弱趋势明显。 相似文献