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1.
THE TYPHOON DISASTERS AND RELATED EFFECTS IN CHINA 总被引：2，自引：0，他引：2
I.liltreductionNatraldisasterisoneofthemajorglobalproblemswithwhichmankindarefacingnowadays,andtrphoondisasterisespeciallyatyPeofgJobaldisasterwiththehighestoccurrencefequencyandmostseriousimpaCt(').AccordingtoStatistics[l],onearth,8otoloOtroPicalcyconesoccurredeveryyear,andcausedanaverageeconowhclossof6to7billionU.S.dolIarsandacasualtyof2O,ooopeople.ThedisaSterscausedbyafeWtaphoonsweremuchmoreaStorushing.Forexample,atropicalstormoccurredinNovemberl97oandanotherinAPrill99lhitBangladesha… 相似文献
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Russell Blong 《The Australian geographer》1997,28(1):7-27
Earthquakes, tropical cyclones and floods are the most important natural perils in terms of human deaths on a global basis. In Australia, at least 4300 deaths in the last 200 years have been produced by heatwaves; about 2000–2200 each by tropical cyclones and floods; and bushfires and lightning strikes have each killed at least 650 people. On a global basis it appears that floods, tropical storms, droughts and earthquakes are the most damaging natural perils. In Australia, in terms of median damage per event, hailstorms are the most expensive insured natural peril, while three events—the 1989 Newcastle earthquake, 1974's Cyclone Tracy, and the 1990 Sydney hailstorm—produced 36 per cent of the total insured damage in the period since 1967. The Newcastle earthquake and the Sydney hailstorm have provided opportunities for new understandings of these perils and their consequences. While much has been learnt from the devastation of Rabaul town by the 1994 eruption, a rare opportunity for a detailed study of building damage has been lost. Without detailed studies, risk rating, where Risk = Hazard (or peril) × Vulnerability, is difficult. 相似文献
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中国登陆热带气旋与太平洋海表温度的关系 总被引：16，自引：0，他引：16
根据1951～2000年中国登陆热带气旋与厄尔尼诺年、拉尼娜年的关系分析,得到了一些重要认识：(1) 在厄尔尼诺年,中国登陆热带气旋数偏少;(2) 厄尔尼诺事件强度越大,中国登陆热带气旋数越少;(3) 厄尔尼诺事件的结束时间若超过5月1日,那么次年中国登陆热带气旋数偏少;(4) 中国登陆热带气旋数的特多年主要集中在拉尼娜年;(5) 在拉尼娜次年,中国登陆热带气旋数偏少;(6) 中国登陆热带气旋强度越大,在厄尔尼诺年出现机会越少;(7) 在厄尔尼诺年,中国初旋偏迟,终旋偏早。同时对其机理进行了探讨。 相似文献
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Fluvial processes, especially rates of floodplain accretion, are less well understood in the wet tropics than in other environments. In this study, the caesium-137 (137Cs) method was used to examine the recent historical sedimentation rate on the floodplain of the Wainimala River, in the basin of the Rewa River, the largest fluvial system in Fiji and the tropical South Pacific Islands. 137Cs activity in the floodplain stratigraphy showed a well-defined profile, with a clear peak at 115 cm depth. Our measured accretion rate of 3.2 cm year−1 over the last ca. 45 years exceeds rates recorded in humid regions elsewhere. This is explained by the high frequency of tropical cyclones near Fiji (40 since 1970) which can produce extreme rainfalls and large magnitude floods. Since the beginning of hydrological records, large overbank floods have occurred every 2 years on average at the study site. The biggest floods attained peak flows over 7000 m3 s−1, or six times the bankfull discharge. Concentrations of suspended sediments are very high (max. 200–500 g l−1), delivered mainly by channel bank erosion. In the future, climatic change in the tropical South Pacific region may be associated with greater tropical cyclone intensities, which will probably increase the size of floods in the Rewa Basin and rates of floodplain sedimentation. 相似文献
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厄尔尼诺事件的强度与登陆广东热带气旋数量的关系初探 总被引：5，自引：1，他引：4
文章对厄尔尼诺事件的强度与登陆广东的热带气旋数量之间的关系进行初步的了统计分析。结果表明: 就总的厄尔尼诺年份来看, 厄尔尼诺事件对登陆广东的热带气旋总数量没有显著的影响;但就具体的厄尔尼诺事件的强度来看, 强、中和弱的厄尔尼诺事件都对登陆广东的热带气旋有明显的影响, 只是强和弱的厄尔尼诺事件使登陆广东的热带气旋数量比非厄尔尼诺年份明显偏少; 而中等厄尔尼诺事件却使登陆广东的热带气旋数量比非厄尔尼诺年份偏多。厄尔尼诺通过影响沃克环流,使沃克环流随着厄尔尼诺强度的不同而产生不同幅度的东移,进而使登陆广东的热带气旋源地的气流出现不同情况,最后影响登陆广东的热带气旋的数量。 相似文献
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Jay S. Hobgood 《自然地理学》2013,34(4):283-291
Traditionally, the development of tropical cyclones has been attributed to the coincidence of warm water, weak upper level divergence, and weak upper level wind shear. In this study, numerical simulations clearly demonstrate the importance of moisture on the intensification of these systems. Simulated tropical cyclones develop more quickly and become more intense when a moister initial sounding is used. Thus, attempts to explain the spatial and temporal distributions of tropical cyclones should include humidity in the list of variables to be examined. 相似文献
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The forests of southeastern Africa are vulnerable to damage imposed by tropical cyclones operating in the South Indian Ocean. We undertook a geographical analysis to determine the relative vulnerability of forests given tropical cyclones recorded during the 1959–2008 storm seasons. From this analysis, eastern coastal forests of Madagascar seem to be the most vulnerable, although return intervals for severe storms vary along the eastern coast, and are shorter (about 10 years) through the central portion of the country. Therefore, the central lowland to upper montane rainforests on the eastern coast seem to be more vulnerable to damage from tropical cyclones than others in the area. While not as extensive, western coastal forests of Madagascar are also as vulnerable in part due to the recurvature of storms in the Mozambique Channel. Though the coastal forests of Mozambique are all nearly equal in terms of vulnerability, the return interval for severe storms to this area is highly variable. The inland Miombo forests of southeast Africa are less vulnerable to damage from tropical cyclones; however, portions of western Mozambique and Zimbabwe have experienced strong tropical storms in the last 50 years. A number of caveats and limitations associated with the data and analyses are noted. Given the broad scale of the study, the relative vulnerability and the return intervals for severe storms should be considered general representations of these phenomena for the southeastern African coast and the island of Madagascar. 相似文献
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西北太平洋热带气旋快速增强与环境垂直风切变统计分析 总被引：1，自引：0，他引：1
利用1990-2009年美国联合台风警报中心整编的热带气旋（TC）最佳路径资料和NCEP/NCAR再分析等压面流场资料,在分析西北太平洋TC每24 h强度变化统计特征的基础上,确定了西北太平洋TC快速增强的阈值,对比不同阈值条件下,TC快速增强初始时刻的强度,TC快速增强发生的季节变化和空间分布特征,进一步研究环境垂直风切变与TC快速增强的关系。结果表明：在西北太平洋海区,当TC强度24 h变化达到样本累积百分率的88%、90%、93%和96%的概率时,对应的强度变化值分别为25 KT、30 KT、35 KT和40 KT,定义它们为TC快速增强的阈值。该阈值越大,快速增强初始时刻的强度也越强。60%左右的TC快速增强发生在8-10月,TC快速增强的空间分布集中于125°-150°E、10°-25°N的矩形区域内。对流层不同层次的垂直风切变与TC快速增强的关系有差异,TC快速增强阈值为40 KT时对应的对流层中上层（200~500 hPa）、对流层中下层（500~850 hPa）和对流层（200~850 hPa）的垂直风切变值的概率分布显示：当垂直风切变≥12 m/s时,分别只有9.7%、1.5%、11.1%的TC可以快速增强;且其与TC快速增强时强度变化的相关系数分别为-0.15、0、-0.04,以200~500 hPa的最为显著,表明对流层中上层垂直风切变对TC强度增强的抑制作用最明显。在TC快速增强阈值为40 KT的初始时刻,将200~850 hPa垂直风切变划分为东风切变和西风切变的统计表明,57%的TC在东风切变的环境下可以快速增强。 相似文献
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基于热带气旋时间、路径、强度数据和中国728个气象站点1951~2014年日降水数据,分析了年和季节极端降水广义极值（GEV）分布函数特征及受热带气旋的影响。通过检查年和各季节极端降水的非一致性,发现具有变异点或显著时间趋势的站点占总站点数的比例较低。仅考虑满足一致性的站点,年和各季节极端降水GEV分布上尾部在全国大部分区域表现出厚尾特征,且不具有上边界。总体来看北方厚尾特征重于南方,秋季和冬季明显高于年和夏季。年极端降水厚尾特征受到不同季节极端降水机制的混合影响。而且,热带气旋对中国沿海区域极端降水有重要影响,往往引发大量级极端降水。东南沿海地区最大10场极端降水由热带气旋引发的比例达到60%以上。因此热带气旋趋向于增加沿海区域年极端降水GEV分布形状参数的大小,并控制着曲线上尾部的形状。 相似文献
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我国干旱区洪水灾害基本特征：以新疆为例 总被引：9，自引：0，他引：9
依据新疆自然和社会环境,分析了新疆洪水及其洪灾的形成,季节分布,年际变化,地区分布等主要特征,并提出对洪水灾害的防御对策。 相似文献
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This research analyzes the relationship between tropical cyclones and fine particulate matter (PM2.5) for landfalling Atlantic tropical cyclones from 2000 to 2015. Daily mean PM2.5 concentrations were collected from the United States Environmental Protection Agency. Tropical cyclone data were acquired from Tropical Prediction Center Best Track Reanalysis in Unisys weather. GRIdded Binary (GRIB formatted) data were downloaded from the Data Support Section of the Computational and Information Systems Laboratory at the National Center for Atmospheric Research (NCAR). Tracks of tropical cyclones were overlaid with the interpolated daily mean PM2.5 concentration value. Results suggest that, in general, tracks are distant from areas with the largest PM2.5 concentrations. To examine the cause-effect nature of this relationship, simulation using the Weather Research and Forecasting (WRF) model suggests that the intensity of Hurricane Lili was weakened only after passing the most PM2.5-polluted area in Louisiana. This result suggests that aerosol loading may weaken the intensity of tropical cyclones, at least in some cases. 相似文献
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The suspected impact of climate warming on precipitation distribution is examined in the Yangtze River Basin. Daily precipitation data for 147 meteorological stations from 1961–2000 and monthly discharge data for three stations in the basin have been analyzed for temporal and spatial trends. The methods used include the Mann–Kendall test and simple regression analysis. The results show (1) a significant positive trend in summer precipitation at many stations especially for June and July, with the summer precipitation maxima in the middle and lower Yangtze River basin in the 1990s; (2) a positive trend in rainstorm frequency that is the main contributor to increased summer precipitation in the basin; and (3) a significant positive trend in flood discharges in the middle and lower basin related to the spatial patterns and temporal trends of both precipitation and individual rainstorms in the last 40 years. The rainstorms have aggravated floods in the middle and lower Yangtze River Basin in recent decades. The observed trends in precipitation and rainstorms are possibly caused by variations of atmospheric circulation (weakened summer monsoon) under climate warming. 相似文献
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玉溪暴雨天气发生规律及成因分析 总被引：4，自引：1，他引：3
1951~2008年玉溪市暴雨发生次数最多的是澄江县,其次是华宁、元江、红塔区。进入21世纪后,随着全球气候变暖,暴雨次数比20世纪明显增多,主要集中在盛夏6~8月,占总次数的72%,其中单点暴雨和小范围暴雨占全部过程暴雨的95%,造成了玉溪市主汛期洪涝灾害频繁发生。形成玉溪暴雨时空分布差异大的天气环流系统主要有切变冷锋型、高原糟冷锋型、两高辐合型、热带天气系统北上型四大类,其次,特殊的地形地貌也是造成玉溪单点暴雨和小范围暴雨较多的原因。 相似文献
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Annual floods in New England (USA) and Atlantic Canada: synoptic climatology and generating mechanisms 总被引：1，自引：1，他引：0
Mathias J. Collins Johnathan P. Kirk Joshua Pettit Arthur T. DeGaetano M. Sam McCown Thomas C. Peterson 《自然地理学》2014,35(3):195-219
New England and Atlantic Canada are characterized by mixed flood regimes that reflect different storm types, antecedent land surface conditions, and flood seasonality. Mixed flood regimes are known to complicate flood risk analyses, yet the synoptic climatology and precipitation mechanisms that generate annual floods in this region have not been described in detail. We analyzed a set of long-term annual flood records at climate-sensitive stream gauges across the region and classified the synoptic climatology of each annual flood, quantitatively describing the precipitation mechanisms, and characterize flood seasonality. We find that annual floods here are dominantly generated by Great Lakes-sourced storms and Coastal lows, known locally as ‘nor’easters.’ Great Lakes storms tend to be associated with lower magnitude annual floods (<75th percentile) and Coastal lows are more clearly associated with higher magnitude events (>75th percentile). Tropical cyclones account for few of all annual floods, including extreme events, despite causing some of the region’s largest and most destructive floods. Late winter/early spring is when the greatest number of annual floods occur region wide, and rainfall is the dominant flood-producing mechanism. Rainfall in combination with snowmelt is also important. Both mechanisms are expected to be impacted by projected regional climate change. We find little evidence for associations between flood-producing synoptic storm types or precipitation mechanisms and large-scale atmospheric circulation indices or time periods, despite upward trends in New England annual flood magnitudes. To more completely investigate such associations, partial duration flood series that include more floods than just the largest of each year, and their associated synoptic climatologies and precipitation mechanisms, should be analyzed. 相似文献
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Li Xia Liu Zhenhai Wang Shaoqiang Li Fengting Li Hui Zhu Tongtong Qian Zhaohui Tu Yongkai Liu Yuanyuan Wang Xiaobo Wang Qinyi Shi Weibo Li Donghui 《地理学报(英文版)》2022,32(9):1831-1846
Journal of Geographical Sciences - In tropical regions, mangrove forests are located in the inter-tidal areas between land and sea, and are at risk from both freshwater and seawater floods. Using... 相似文献
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Unseasonable floods are floods that occur in the season of lowest flood frequency, or dry season. Such floods pose a unique problem to flood planners and forecasters, yet little research has investigated the physical processes associated with unseasonable floods. The purpose of this study is to construct a synoptic climatology of extreme unseasonable floods for the southeastern United States. Results indicate that the types of storms creating unseasonable floods are location specific, with four unique regions across the study area: Carolina (tropical storms/hurricanes), Georgia Coastal Plain (Gulf depressions), Gulf-Atlantic (frontal), and Tennessee (frontal with upper-air enhancement). The precipitation created by these storms is low to moderate, rarely exceeding the 10-year 24-hour storm total. The precipitation levels suggest that a combination of meteorological conditions and land-surface conditions create the extreme events. A statistical analysis indicates that high soil-moisture levels combine with the moderate rains to produce extreme unseasonable floods. [Key words: unseasonable floods, synoptic climatology, land-surface conditions, southeastern United States.] 相似文献
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The Queensland Gold Coast has been Australia's premier holiday resort for more than 20 years, and has had increasing attraction as a retirement area for people from elsewhere in Australia. A mixture of canal estates, beach-front residences, retail trade outlets and high-rise apartment and hotel buildings extends onto the fore-dune. Tropical cyclones approaching the area have caused widespread damage to public and private property, and a recent analysis has pointed to the Gold Coast as one of the areas potentially vulnerable to the effects of super tropical cyclones. The nature and extent of hazard awareness and of public and private loss mitigation measures and their overall effectiveness are critical, if property damage and threats to life and the local economy are to be kept to a minimum. Surveys of hazard awareness of Gold Coast residents and of their approaches to loss mitigation and adjustment indicate a low level of preparedness despite past tropical cyclones, and point to the need for better public education. 相似文献