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1.
本文对汛期长江流域特大暴雨及洪涝成因进行了分析,认为与越赤道气流异常及受"非亚支宏观气流系统"的影响有关.同时指出,长江流域的特大暴雨及洪涝灾害不但可以预测,并且能够采取措施予以减弱. 相似文献
2.
利用1951～2002年全国733个测站经过非均一性检验的月平均气温资料,在剔除50万以上人口大城市测站后,分析了52年来中国东、西部及青藏高原地区的气温变化趋势的一致性和差异性,并讨论了其可能原因.结果表明我国东、西部地区年、季平均气温变化有着较好的一致性;近52年来,我国东、西部和青藏高原地区年平均气温均呈升温趋势,年平均气温的增温速率东部为026℃/10a,西部018℃/10a,东部比西部高008℃/10a;季平均气温东部地区冬、春季的增暖趋势大于西部和青藏高原,而其夏、秋季的增暖趋势小于西部和青藏高原.我国东、西部地区年、季平均气温变化关系密切,说明其主要是受全球气候变化的影响而变化,但东部年平均气温的增暖总趋势大于西部,又说明地域差异在气温变化中也有重要作用. 相似文献
3.
应用 １００ｈＰａ、５００ｈＰａ月平均高度资料、海温、射出长波辐射（ＯＬＲ）及武汉的气温 和降水资料,对１９９８年长江中游特大洪涝的成因作了总结分析．结果表明,冬春厄尔尼诺、副 热带高压和从春到初夏期间,印度洋－西太平洋赤道辐合带（ＩＴＣＺ）南侧积云对流的异常较 强,以及冬季雨雪异常偏多等气候特点,是有利于洪涝发生的强信号． 相似文献
4.
1998年中国特大洪涝时期的环流特征 总被引：14，自引：3，他引：11
研究了 1 998年我国特大洪涝的环流特征 ,长江流域洪涝年全国有两种降水分布型 :即长江流域大水全国降水偏多型及长江流域大水其南北降水偏少型 .进而 ,研究了这两类分布型的环流特征 ,并指出北半球 50 0hPa位势高度场有着显著的差异 .鄂霍茨克海高压的建立是长江流域多雨的重要条件 ,南海高压的强弱在全国降水分布型中起着重要的作用 相似文献
5.
1998年，长江流域发生了类似1954年的百年一遇全江性大洪水，1999年长江又发生了较大洪水。在上述背景下，长江中下游地区是否会发生中强震，需要进行认真的探讨。初步研究结果表明，长江大洪水之后3年内，鄂、湘沿江地区中经地震受长江大洪水的“耦合振荡”作用较大。 相似文献
6.
基于24个CMIP5全球耦合模式模拟结果,分析了中国区域年平均降水和ETCCDI强降水量(R95p)、极端强降水量(R99p)对增暖的响应.定量分析结果显示,CMIP5集合模拟的当代中国区域平均降水对增温的响应较观测偏弱,而极端降水的响应则偏强.对各子区域气温与平均降水、极端降水的关系均有一定的模拟能力,并且极端降水的模拟好于平均降水.RCP4.5和RCP8.5情景下,随着气温的升高,中国区域平均降水和极端降水均呈现一致增加的趋势,中国区域平均气温每升高1℃,平均降水增加的百分率分别为3.5%和2.4%,R95p增加百分率为11.9%和11.0%,R99p更加敏感,分别增加21.6%和22.4%.就各分区来看,当代的区域性差异较大,未来则普遍增强,并且区域性差异减小,在持续增暖背景下,中国及各分区极端降水对增暖的响应比平均降水更强,并且越强的极端降水敏感性越大.未来北方地区平均降水对增暖的响应比南方地区的要大,青藏高原和西南地区的R95p和R99p增加最显著,表明未来这些区域发生暴雨和洪涝的风险将增大. 相似文献
7.
长江和淮河流域汛期洪涝大气环流特征的比较 总被引：5，自引：0，他引：5
利用1990~2010年我国756站汛期(6~7月)逐日降水资料及NCEP逐日再分析资料,选取了这21年间分别发生在我国长江及淮河流域洪涝的典型年份,进行了汛期大气环流场及物理量场的合成分析,结果表明:长江与淮河流域汛期洪涝年的大气环流及物理量场有很大差异.在长江流域汛期洪涝年,南亚高压中心偏东,乌拉尔山及鄂霍次克海区域上空维持着阻塞高压系统,梅雨锋维持在30°N附近;而在淮河流域洪涝年,南亚高压中心位置偏西,北半球中高纬大气环流呈经向型,梅雨锋维持在33°N附近.此外,长江与淮河流域汛期洪涝的水汽来源及输送也有很大不同,长江流域汛期洪涝的水汽输送气流有两支,分别是来自孟加拉湾的西南气流和我国南海季风,这两支气流在我国长江流域上空交汇;而淮河流域汛期洪涝的两支水汽输送气流分别是我国东南洋面上的东南季风及我国南海季风,这两支季风气流在我国淮河流域上空交汇. 相似文献
8.
研究地球水文变化的日地物理成因和规律的日地水文学（Solar-TerrestrialHydrology），用于水、旱灾害预测多次获得证实.本文从日地水文物理基础、长江淮河22年周期性大洪水、黄河大洪水和太阳活动关系、太阳活动双重衰减期北方大旱、17世纪日地水文异常变化、太阳活动对暴雨洪水中短期影响、台湾海峡两侧大暴雨洪水落区转移、全球最大洪水日地水文研究以及学科发展和应用前景九个方面，对中国近70多年来的主要成果加以回顾和总结.基础科学、高科技和应用紧密结合，促成对国民经济发展直接相关的新学科，是当代科学进步的一个显著标志，这里又是一个例证． 相似文献
9.
1993年太湖流域的洪涝灾害及水利工程的作用 总被引：2，自引：1，他引：1
1993年汛期太湖最高水位高居建国以来的第3位,仅次于1991年和1954年,达到4.51m(平均水位,下同),局部地区发生了洪涝灾害。本文对1993年太湖流域汛期的雨情和水情做了论述,并对1993、1991、1954年三个典型大水年的降雨和洪水特征作了比较。同时,还对洪涝灾害和水利工程的作用进行分析。太湖流域的雨季一般为5—7月,但是1993年汛期的降雨在时间上的分布有些异常。降雨集中在8月,而河道最高水位则出现在8月下旬。降雨的空间分布有以下3个特征:(1)上游地区的降雨集中在浙西山区;(2)太湖湖区的降雨量很大;(3)下游地区的降雨集中在淀泖和杭嘉湖地区。淀泖和杭嘉湖地区一些水位站的实测河道水位,比发生大洪水的1991年还要高。发生洪涝灾害的原因可归纳为,上游地区洪水来量大,当地的降雨强度高,以及下游河道排水不畅通。为了改进防汛调度和完善治理规划,需要对不同典型洪水年份的降雨和洪水模式做进一步研究。 相似文献
10.
利用近50年华北地区26个站逐月降水观测资料和全球大气海洋分析资料,分析了华北降水的年代际变化特征及其和全球海气系统年代际变化的关系.对华北降水距平指数变化分析表明,近50年来华北降水具有减少的总体趋势,叠加在该趋势之上的是年代际变化,其中1965年和1980年发生了两次跃变,使得20世纪80年代干旱尤为严重.在对华北地区降水年代际变化特征分析的基础上,揭示了与华北降水年代际异常相伴随的大气环流和上层海洋热力异常型.结果表明,华北降水年代际异常与太平洋上层海洋热力状况异常有显著关系,主要表现为太平洋年代际振荡（PDO）与华北降水异常的相关.在年代际时间尺度上,华北干旱与上层海洋热力及大气环流异常的配置关系如下：当华北地区干旱时,则热带中东太平洋海温偏高,北太平洋中部海温偏低,即太平洋上主要表现为PDO暖位相,全球大部分地区（包括华北地区）气温偏高,青藏高原地区气温偏低,日本北部及东西伯利亚气压异常偏低,华北及其以南大片地区气压偏高,华北地区由异常西北风控制,不利于水汽向华北地区输送. 相似文献
11.
1840年以来长江大洪水演变与气候变化关系初探 总被引：25，自引：3，他引：22
长江洪水灾害是我国频率高、为患严重的自然灾害之一.本文依据可靠资料,选择1840年至2000年间32次大洪水记录,探讨其演变与气候变化的关系.认知1910s前的19世纪冷期出现大洪水13次(包括1870年的极值大洪水事件)频率为1.9次／10a.1921-2000年间出现了大洪水19次,频率为2.4次／10a.20世纪暖期又分出两个变暖时段,前一变暖时段的峰值期1920s-1940s出现大洪水9次,包含1931年全流域大洪水.后一变暖时段,即1980s与1990s出现大洪水8次.实测记录到的最大洪水1954年位于前一变暖时段结束阶段.1990s是全球,也是我国近百年中最暖年代,受东南季风影响大的中下游地区夏季降水量是近百年最多的,大暴雨频率也是有较多记录的40年来最高的.以此出现了10年5次大洪水高频率现象,包含1998年全流域型大洪水,表明了全球变暖的显著影响.也指示30-40年问周期性振荡中多雨年代.如此可预期21世纪初期降水会有小幅度下降与大洪水频率在短期内降低的可能性.长江上游受西南季风影响较大,19世纪下半期与20世纪上半期为多降水期,大洪水频率较高.20世纪下半期为少降水期,大洪水频率较低.关于气候变化研究有待深入,前景不易预估. 相似文献
12.
江淮流域是我国暴雨频发的地区之一,而乌拉尔山阻塞高压和西太平洋副热带高压是北半球两个主要的大气环流系统.本文统计分析了1971~2003年期间乌山阻塞高压和西太平洋副高的逐日强度变化特征,研究了乌山阻塞高压和西太平洋副高对江淮流域强暴雨过程的响应关系.结果表明,江淮流域多数强暴雨过程发生在乌山阻高的减弱期,在乌山阻高的建立和加强期较少有持续性暴雨发生.乌山阻高的突然减弱是江淮流域强暴雨过程发生的强信号之一.同时,西太平洋副热带高压的加强西伸登陆是江淮流域强暴雨过程发生的必要条件之一. 相似文献
13.
ENSO和长江大水对天文因子的响应研究 总被引：5，自引：1，他引：4
ENSO（厄尔尼诺和南方涛动的总称）对世界尺度的天气气候有影响,本文用概率论统计检验方法,查明长江大水与ENSO以及ENSO与天文因子的相关关系,并系统分析了三者之间的相关关系。结果表明:ENSO事件对天文物理主周期和天文特征有明显的响应,长江大水年对太阳活动特征、节气日的月相年变化和ENSO也有显著的响应关系。这些关系对长江大水的准确预测有重要价值。文中对天文物理因子对ENSO和大水的影响机理进行了探讨。 相似文献
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A comparative study of the atmospheric circulations associated with rainy-season floods between the Yangtze and Huaihe River Basins 总被引：1，自引：0，他引：1
Here we present the results from the composite analyses of the atmospheric circulations and physical quantity fields associated with rainy-season for the selected floods cases over the Yangtze and Huaihe River basins for the 21 years(1990–2010),using the daily rain gauge measurements taken in the 756 stations throughout China and the NCEP/reanalysis data for the rainyseasons(June–July)from 1990 to 2010.The major differences in the atmospheric circulations and physical quantity fields between the Yangtze and Huaihe River basins are as follows:for flooding years of the Yangtze River Basin,the South Asia high center is located further east than normal,the blocking high over the Urals and the Sea of Okhotsk maintains,and the Meiyu front is situated near 30°N whereas for flooding years of the Huaihe River Basin,the South Asia high center is further west than normal,the atmospheric circulations over the mid and high latitudes in the Northern Hemisphere are of meridional distribution,and the Meiyu front is situated near 33°N.In addition,there are distinct differences in water vapor sources and associated transports between the Yangtze and Huaihe River basins.The water vapor is transported by southwesterly flows from the Bay of Bengal and monsoon flows over the South China Sea for flooding years of the Yangtze River Basin whereas by southeast monsoons from the eastern and southern seas off China and monsoon flows over the South China Sea for flooding years of the Huaihe River Basin. 相似文献
15.
16.
Teleconnection between the Indian summer monsoon onset and the Meiyu over the Yangtze River Valley 总被引：11，自引：0，他引：11
Based on the Indian and Chinese precipitation data and the NCEP-NCAR reanalysis circulation data, the relationship between the Indian summer monsoon (ISM) onset and the Meiyu over the Yangtze River Valley has been discussed by the methods of correlation analysis and composite analysis. The results show that the date of ISM onset over Kerala in the southwestern coast of the Indian Peninsula is about two weeks earlier than the beginning of the Meiyu over the Yangtze River Valley. After the outbreak of ISM, the teleconnection mode sets up from the western coast of India via the Bay of Bengal (BOB) to the Yangtze River Valley and southern Japan. It is different both in time and space from the telecon- nection mode which is from the northwest of India via the Tibetan Plateau to northern China. The for- mer mode is defined as the "south" teleconnection of the Asian summer monsoon, forming in the pe- riod of ISM onset; while the latter mode is called the "north" teleconnection, mainly occurring in the Asian monsoon culminant period. During the process of the "south" teleconnection’s formation, the Asian monsoon circulation has experienced a series of important changes: ISM onset, the northward movement of the south Asia high (SAH), the onset vortex occurrence, the eastward extension of the stronger tropical westerly belt, and the northeastward jump of the western Pacific subtropical high (WPSH), etc. Consequently, since ISM sets up over Kerala, the whole Asian continent is covered by the upper SAH after about two weeks, while in the mid- and lower troposphere, a strong wind belt forms from the Arabian Sea via the southern India, BOB and the South China Sea (SCS), then along the western flank of WPSH, to the Yangtze River Valley and southern Japan. With the northward moving of the subtropical jet streams, the upper westerly jet stream and the low level jet have been coupled ver- tically over east Asia, while the Yangtze River Valley happens to locate in the ascending motion area between the upper jet stream and the low level jet, i.e. right of the entrance of the upper jet stream and left of the low level jet. Such a structure of the vertical circulation can trigger the Meiyu onset over the Yangtze River Valley. 相似文献
17.
Huanghe Gu Zhongbo Yu Guiling Wang Jigan Wang Qin Ju Chuanguo Yang Chuanhao Fan 《Stochastic Environmental Research and Risk Assessment (SERRA)》2015,29(3):693-707
The recent (1970–1999) and future (2070–2099) climates under the SRES A1B scenario, simulated by the regional climate model RegCM4.0 driven with lateral boundary conditions from the ECHAM5 general circulation model, are utilized to force a large-scale hydrological model for assessing the hydrological response to climate changes in the Yangtze River Basin, China. The variable infiltration capacity model (VIC) is utilized to simulate various hydrological components for examining the changes in streamflow at various locations throughout the Yangtze River Basin. In the end of the twenty-first century, most of the Yangtze River Basin stands out as “hotspots” of climate change in China, with an annual temperature increase of approximately 3.5 °C, an increase of annual precipitation in North and a decrease in South. Runoff in the upper reach of Yangtze River is projected to increase throughout the year in the future, especially in spring when the increase will be approximately 30 %. Runoff from the catchments in the northern part of Yangtze River will increase by approximately 10 %, whereas that in the southern part will decrease, especially in the dry season, following precipitation changes. The frequency of extreme floods at three mainstream stations (Cuntan, Yichang, and Datong) is projected to increase significantly. The original extreme floods with return periods of 50, 20, and 10 years will change into floods with return periods of no more than 20, 10, and 5 years. The projected increase in extreme floods will have significant impacts on water resources management and flood control systems in the Yangtze River Basin. 相似文献
18.
长江下游—南黄海地震带位于华北地震区东南部, 带内地震主要受长江下游和南黄海海域内一系列断裂的控制, 以中强地震活动为主, 是地震活动较强的地区。 本文充分利用该带最新的区域地震台网资料, 历史地震复核资料以及地震构造等资料, 统计和计算了b值、 V4和中小地震能量密度值, 探讨了带内b值空间分布与历史强震、 中小地震能量密度值空间分布的关系, 进一步研究了长江下游—南黄海地震带的地震活动性特征。 通过本文的研究, 获得了长江下游—南黄海地震带的地震活动性参数, 为概率危险性分析提供计算参数; 探讨了该带未来百年地震发展趋势, 初步判定了该带潜在地震危险区, 为地震活动中长期预测提供参考依据和方法; 研究结果对地震区划、 工程场地地震安全性评价、 地震活动中长期预测均有重要意义。 相似文献
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Effects of the Changjiang river discharge on sea surface warming in the Yellow and East China Seas in summer 总被引：2，自引：0，他引：2
Taewook Park Chan Joo Jang Johann H. JungclausHelmuth Haak Wonsun ParkIm Sang Oh 《Continental Shelf Research》2011,31(1):15-22
This study explores the effects of the Changjiang (also called the Yangtze River) river discharge (CRD) on the density stratifications and associated sea surface temperature (SST) changes using a global ocean general circulation model with regional focus on the Yellow and East China Seas (YECS). It is found that CRD increases the SST in summer through a barrier layer (BL) formation that tends to enhance stratification at the mixed layer base, and thus reduces both vertical mixing and entrainment. This process is effective, particularly in August, after the CRD reaches its maximum in July. The SST difference between the composites of flood and drought years confirms that the surface warming is related to surface freshening by the CRD. This result suggests that the BL induced by the CRD is an important contributor to the surface heat budget in the YECS. 相似文献
20.
Based on historical records and crop harvest scores extracted from historical documents, this study reconstructed the spatial–temporal distribution and severities of floods in the Yangtze-Huai River valley (YHRV) in 1823 and 1849. We also summarized the effects of the floods on society and identified government measures taken to cope with the floods in the context of the economic recession in the period of 1801–1850. The 1823 flood, which was caused by the heavy precipitation of the Meiyu period and typhoons, severely affected areas in the lower reaches of the Yangtze River. Meanwhile, the 1849 flood, triggered by long-term, high-intensity Meiyu precipitation in the middle and lower reaches of the Yangtze River, mainly affected areas along the Yangtze River. The 1849 disaster was more serious than the one in 1823. In the lower reaches of the Yangtze River, the 1849 flood caused the worst agricultural failure of the period 1730–1852. To deal with the disasters, the Qing government took relief measures, such as exempting taxes in the affected areas, distributing grain stored in warehouses, and transferring grain to severely afflicted areas. These relief measures were supplemented by auxiliary measures, such as exempting commodity taxes on grain shipped to disaster areas and punishing officials who failed to provide adequate disaster relief. The flood disasters disrupted the water system of the Grand Canal and forced the Qing government to transport Cao rice by sea beginning in 1826. This laid the groundwork for the rise of coastal shipping in modern China. With the economic recession of the 19th century, Chinese society was not as resilient to floods as it was in the 18th century. Compared to droughts, floods are more difficult to deal with and pose greater threats to infrastructure and normal life and work in the cities. 相似文献