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1.
台风、强台风和热带低压可统称为热带气旋,本文统计了1949—1985年登陆和影响我国沿海各省、市、自治区的热带气旋频数、路径和登陆时中心附近地面最大风速、最低气压等,并进行了分析。一、登陆和影响我国沿海地区的热带气旋频数。  相似文献   

2.
浙江影响热带气旋的几个统计特征   总被引:1,自引:0,他引:1  
许浩恩  陈海燕  赵璐 《浙江气象》2009,30(2):4-8,21
利用1949-2007年热带气旋资料(由于多年沿用习惯,本文将近中心最大风力≥8级的热带风暴统称台风)对影响浙江热带气旋进行了定义,从而对影响浙江台风的频数、台风暴雨、台风大风进行了统计分析。分析表明:浙江各地受台风影响的频数自东向西递减,年均受台风影响次数最多的是东部沿海地区;登陆台风个数有增加趋势;影响台风集中在7—9月份;各月台风降水空间分布有一定差异,东南部沿海地区降水影响明显;东部沿海是台风大风频发区。  相似文献   

3.
根据1949~2011年热带气旋路径资料,统计分析了影响珠江口海域的热带气旋气候特征,包括热带气旋频数、强度及路径趋向等特征,结果显示,在近63a间共有75个热带气旋样本影响珠江口海域,有3个年份出现多达4个热带气旋影响该海域;出现12级以上强风的台风样本约占总数的3成;热带气旋的移动方向以西北和偏西方向为主,约占总数的7成.分别采用x2检验和Колмогоров法对热带气旋样本频数及最大风速序列分别进行拟合适度检验,结果表明,影响珠江口海域的热带气旋最大风速服从Poisson-Gumbul复合极值分布,计算影响珠江口海域的热带气旋中心附近的概率风速,得到的50a一遇10min平均风速为51.1m.s-1,100a一遇10min平均风速为56.8m/s.  相似文献   

4.
杨梦兮  班欣 《气象科技》2014,42(3):524-529
在对江苏北部沿海9个国家基本(一般)气象站近60年来热带气旋样本统计分析基础之上,结合近4年闪电定位仪资料,分析了影响江苏北部沿海地区的热带气旋、沿海大风和闪电的时空分布规律及其可能对该区域风电场造成的影响。结果表明:①影响江苏北部沿海地区的热带气旋以西北行路径和登陆后北上出海居多,占总数的73.2%;②建国以来影响该区域的热带气旋中,有87.7%的热带气旋可为风电场带来经济效益,进行适当防御后不会造成损失的占12.3%,尚无破坏型热带气旋个例;③江苏北部沿海地区雷雨季节(6—8月)应加强对机组的防雷检查,特别是江苏北部沿海地区的盐城区段更应加强雷电防护监测工作;④江苏北部沿海地区50年一遇最大风速和极大风速符合国家Ⅲ/Ⅱ型风机安全运行标准。  相似文献   

5.
西北太平洋热带气旋频数和强度变化趋势初探   总被引:4,自引:0,他引:4       下载免费PDF全文
利用1951—2006年西北太平洋 (含南海) 热带气旋资料, 研究了不同强度热带气旋的气候变化特征。结果表明:超强台风 (近中心最大风速≥58m/s, 简称超强台风Ⅱ) 频数、强度和初、终旋日期的变化特征都不同于其他级别热带气旋; 西北太平洋热带气旋的总频数有长期减少趋势, 主要由热带低压和超强台风Ⅱ的长期减少趋势引起; 随着热带气旋强度增强, 出现月最大频数的月份逐渐推迟; 超强台风月频数最大值发生在秋季; 超强台风Ⅱ频数的年变化与除了超强台风Ⅰ(近中心最大风速为51~58m/s) 外的其他级别热带气旋反相关; 受超强台风Ⅱ减少影响, 热带气旋年平均最大风速有减小的长期趋势; 热带气旋的初、终旋日期没有显著的长期变化趋势, 但超强台风Ⅱ的初旋日期有推迟趋势, 终旋日期有提前趋势, 发生时间缩短。  相似文献   

6.
利用1949~2010年广西88个气象观测站的降水资料和1961~2010年NCEP/NCAR再分析资料,分析了影响广西热带气旋的数量、路径及其影响广西暴雨的特征,通过数值模拟研究了广西大范围暴雨物理量环境场的变化特征,结果表明:影响广西热带气旋个数有显著的减少趋势,并存在着明显的2a、4a和10a周期振荡信号,年日最多暴雨站数有增多的趋势。热带气旋影响下沿海地区发生暴雨的可能性最大,桂北山区最小。热带气旋从沿海地区登陆进入广西,造成广西各站发生暴雨概率最高,其次为从梧州、玉林进入广西的路径,最少的为热带气旋在北部湾西行进入越南。热带气旋的中低层环流中心一般为强降水区域,中心滞留时间越长降雨量越大,极大风速始终位于台风前进方向的右侧,大范围暴雨区域位于急流的左侧。在热带气旋影响日最多暴雨站数发生时中低层风速及高度场在近30年的变化特征:广西的东北面存在一个呈西北-东南向的风速增高带,西南面为风速减弱带;西北面为高度场减弱区,黄海一带为一个显著增强区。  相似文献   

7.
近20 a影响我国台风活动变化趋势   总被引:13,自引:10,他引:3  
利用最新定义的气旋活动指数CAI(Cyclone Activity Index)分析影响我国台风活动近20 a的变化趋势及其可能原因。分析发现,影响我国的台风频数自1996年以来显著减少,主要表现为南方沿海地区热带气旋影响减小,三亚和海口更呈显著下降的趋势(通过信度为0.05的统计检验),而东南方沿海地区热带气旋影响明显增加,厦门、福州、温州、杭州和上海夏季(6—10月)受到影响的程度显著上升(福州、温州和杭州通过信度为0.05的统计,上海和厦门通过信度为0.1的统计检验)。进一步分析表明,热带气旋活动的这些变化与台风盛行路径和强度的变化有密切关系。  相似文献   

8.
热带气旋对中国沿海风电开发的影响   总被引:2,自引:0,他引:2  
利用1961-2006年热带气旋(TC)资料,选取进入距海岸3个纬距左右警戒区的TC为影响中国沿海风电开发的TC;根据风电工程风电机组(WTGS)安全等级,详细分析了影响中国沿海地区TC路径、强度、风力的气候特征,发现进入警戒区后台风和强热带风暴占59.5%,超强台风、强台风占总频数的21.5%;TC造成的10分钟平均最大风速40m·s~(-1)以上的区域集中在珠江口以东的广东沿海和海南东部沿海和浙闽交界处;登陆福建及以北沿海强度达台风以上的常造成≥25m·s~(-1)的强风,而在福建以南登陆并造成强风的为强热带风暴以上;福建中南部沿海TC大风的可利用率达80%以上;TC威胁风电机组安全的区域主要在浙江的中部沿海、浙闽交界处沿海和珠江口以东的广东沿海.  相似文献   

9.
影响中国的热带气旋极端事件年代际变化   总被引:1,自引:0,他引:1  
利用1949—2009年影响中国的热带气旋风雨资料以及登陆信息,研究影响热带气旋极端事件的年代际变化特征。结果表明:热带气旋登陆极端偏早或偏晚事件在1970和2000年代发生较少。热带气旋登陆强度(中心附近最大风力和最低气压)极端事件在2000年代发生频数最高。热带气旋降水影响时间极端事件在1970年代频数最多,大风影响时间极端事件在1980年代频数最多。日降水量和过程降水量的极值站数在1960年代最多,日最大风速极值站数在1980年代最多。  相似文献   

10.
李畅  姜霞  沈新勇 《山东气象》2021,41(4):62-72
利用印度气象局(India Meteorological Department,IMD)、国际气候管理最佳路径档案库(International Best Track Archive for Climate Stewardship,IBTrACS)提供的1982—2020年阿拉伯海热带气旋路径资料,美国国家环境预报中心(National Centers for Environmental Prediction,NCEP)再分析资料,对近39 a阿拉伯海热带气旋源地和路径特征、活跃区域、频数及气旋累积能量(accumulated cyclone energy,ACE)指数的季节特征和年际变化特征进行分析,并结合环境因素,说明其物理成因。结果表明:阿拉伯海热带气旋多发于10°~25°N,65°~75°E海域,5—6月、9—12月发生频数较高且强度较强,1—4月、7—8月发生频数较低且气旋近中心最大风速均小于35 kn;频数的季节变化主要受控于垂直风切变要素;阿拉伯海热带气旋发生频数和ACE近年有上升趋势,年际变化主要受控于海面温度(sea surface temperature,SST)和850 hPa相对湿度要素。  相似文献   

11.
Using the International Comprehensive Ocean-Atmosphere Data Set(ICOADS) and ERA-Interim data, spatial distributions of air-sea temperature difference(ASTD) in the South China Sea(SCS) for the past 35 years are compared,and variations of spatial and temporal distributions of ASTD in this region are addressed using empirical orthogonal function decomposition and wavelet analysis methods. The results indicate that both ICOADS and ERA-Interim data can reflect actual distribution characteristics of ASTD in the SCS, but values of ASTD from the ERA-Interim data are smaller than those of the ICOADS data in the same region. In addition, the ASTD characteristics from the ERA-Interim data are not obvious inshore. A seesaw-type, north-south distribution of ASTD is dominant in the SCS; i.e., a positive peak in the south is associated with a negative peak in the north in November, and a negative peak in the south is accompanied by a positive peak in the north during April and May. Interannual ASTD variations in summer or autumn are decreasing. There is a seesaw-type distribution of ASTD between Beibu Bay and most of the SCS in summer, and the center of large values is in the Nansha Islands area in autumn. The ASTD in the SCS has a strong quasi-3a oscillation period in all seasons, and a quasi-11 a period in winter and spring. The ASTD is positively correlated with the Nio3.4 index in summer and autumn but negatively correlated in spring and winter.  相似文献   

12.
The spatial and temporal variations of daily maximum temperature(Tmax), daily minimum temperature(Tmin), daily maximum precipitation(Pmax) and daily maximum wind speed(WSmax) were examined in China using Mann-Kendall test and linear regression method. The results indicated that for China as a whole, Tmax, Tmin and Pmax had significant increasing trends at rates of 0.15℃ per decade, 0.45℃ per decade and 0.58 mm per decade,respectively, while WSmax had decreased significantly at 1.18 m·s~(-1) per decade during 1959—2014. In all regions of China, Tmin increased and WSmax decreased significantly. Spatially, Tmax increased significantly at most of the stations in South China(SC), northwestern North China(NC), northeastern Northeast China(NEC), eastern Northwest China(NWC) and eastern Southwest China(SWC), and the increasing trends were significant in NC, SC, NWC and SWC on the regional average. Tmin increased significantly at most of the stations in China, with notable increase in NEC, northern and southeastern NC and northwestern and eastern NWC. Pmax showed no significant trend at most of the stations in China, and on the regional average it decreased significantly in NC but increased in SC, NWC and the mid-lower Yangtze River valley(YR). WSmax decreased significantly at the vast majority of stations in China, with remarkable decrease in northern NC, northern and central YR, central and southern SC and in parts of central NEC and western NWC. With global climate change and rapidly economic development, China has become more vulnerable to climatic extremes and meteorological disasters, so more strategies of mitigation and/or adaptation of climatic extremes,such as environmentally-friendly and low-cost energy production systems and the enhancement of engineering defense measures are necessary for government and social publics.  相似文献   

13.
Various features of the atmospheric environment affect the number of migratory insects, besides their initial population. However, little is known about the impact of atmospheric low-frequency oscillation(10 to 90 days) on insect migration. A case study was conducted to ascertain the influence of low-frequency atmospheric oscillation on the immigration of brown planthopper, Nilaparvata lugens(Stl), in Hunan and Jiangxi provinces. The results showed the following:(1) The number of immigrating N. lugens from April to June of 2007 through 2016 mainly exhibited a periodic oscillation of 10 to 20 days.(2) The 10-20 d low-frequency number of immigrating N. lugens was significantly correlated with a low-frequency wind field and a geopotential height field at 850 h Pa.(3) During the peak phase of immigration, southwest or south winds served as a driving force and carried N. lugens populations northward, and when in the back of the trough and the front of the ridge, the downward airflow created a favorable condition for N. lugens to land in the study area. In conclusion, the northward migration of N. lugens was influenced by a low-frequency atmospheric circulation based on the analysis of dynamics. This study was the first research connecting atmospheric low-frequency oscillation to insect migration.  相似文献   

14.
The atmospheric and oceanic conditions before the onset of EP El Ni?o and CP El Ni?o in nearly 30 years are compared and analyzed by using 850 hPa wind, 20℃ isotherm depth, sea surface temperature and the Wheeler and Hendon index. The results are as follows: In the western equatorial Pacific, the occurrence of the anomalously strong westerly winds of the EP El Ni?o is earlier than that of the CP El Ni?o. Its intensity is far stronger than that of the CP El Ni?o. Two months before the El Ni?o, the anomaly westerly winds of the EP El Ni?o have extended to the eastern Pacific region, while the westerly wind anomaly of the CP El Ni?o can only extend to the west of the dateline three months before the El Ni?o and later stay there. Unlike the EP El Ni?o, the CP El Ni?o is always associated with easterly wind anomaly in the eastern equatorial Pacific before its onset. The thermocline depth anomaly of the EP El Ni?o can significantly move eastward and deepen. In addition, we also find that the evolution of thermocline is ahead of the development of the sea surface temperature for the EP El Ni?o. The strong MJO activity of the EP El Ni?o in the western and central Pacific is earlier than that of the CP El Ni?o. Measured by the standard deviation of the zonal wind square, the intensity of MJO activity of the EP El Ni?o is significantly greater than that of the CP El Ni?o before the onset of El Ni?o.  相似文献   

15.
Storms that occur at the Bay of Bengal (BoB) are of a bimodal pattern, which is different from that of the other sea areas. By using the NCEP, SST and JTWC data, the causes of the bimodal pattern storm activity of the BoB are diagnosed and analyzed in this paper. The result shows that the seasonal variation of general atmosphere circulation in East Asia has a regulating and controlling impact on the BoB storm activity, and the “bimodal period” of the storm activity corresponds exactly to the seasonal conversion period of atmospheric circulation. The minor wind speed of shear spring and autumn contributed to the storm, which was a crucial factor for the generation and occurrence of the “bimodal pattern” storm activity in the BoB. The analysis on sea surface temperature (SST) shows that the SSTs of all the year around in the BoB area meet the conditions required for the generation of tropical cyclones (TCs). However, the SSTs in the central area of the bay are higher than that of the surrounding areas in spring and autumn, which facilitates the occurrence of a “two-peak” storm activity pattern. The genesis potential index (GPI) quantifies and reflects the environmental conditions for the generation of the BoB storms. For GPI, the intense low-level vortex disturbance in the troposphere and high-humidity atmosphere are the sufficient conditions for storms, while large maximum wind velocity of the ground vortex radius and small vertical wind shear are the necessary conditions of storms.  相似文献   

16.
Observed daily precipitation data from the National Meteorological Observatory in Hainan province and daily data from the National Centers for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) reanalysis-2 dataset from 1981 to 2014 are used to analyze the relationship between Hainan extreme heavy rainfall processes in autumn (referred to as EHRPs) and 10–30 d low-frequency circulation. Based on the key low-frequency signals and the NCEP Climate Forecast System Version 2 (CFSv2) model forecasting products, a dynamical-statistical method is established for the extended-range forecast of EHRPs. The results suggest that EHRPs have a close relationship with the 10–30 d low-frequency oscillation of 850 hPa zonal wind over Hainan Island and to its north, and that they basically occur during the trough phase of the low-frequency oscillation of zonal wind. The latitudinal propagation of the low-frequency wave train in the middle-high latitudes and the meridional propagation of the low-frequency wave train along the coast of East Asia contribute to the ‘north high (cold), south low (warm)’ pattern near Hainan Island, which results in the zonal wind over Hainan Island and to its north reaching its trough, consequently leading to EHRPs. Considering the link between low-frequency circulation and EHRPs, a low-frequency wave train index (LWTI) is defined and adopted to forecast EHRPs by using NCEP CFSv2 forecasting products. EHRPs are predicted to occur during peak phases of LWTI with value larger than 1 for three or more consecutive forecast days. Hindcast experiments for EHRPs in 2015–2016 indicate that EHRPs can be predicted 8–24 d in advance, with an average period of validity of 16.7 d.  相似文献   

17.
Based on the measurements obtained at 64 national meteorological stations in the Beijing–Tianjin–Hebei (BTH) region between 1970 and 2013, the potential evapotranspiration (ET0) in this region was estimated using the Penman–Monteith equation and its sensitivity to maximum temperature (Tmax), minimum temperature (Tmin), wind speed (Vw), net radiation (Rn) and water vapor pressure (Pwv) was analyzed, respectively. The results are shown as follows. (1) The climatic elements in the BTH region underwent significant changes in the study period. Vw and Rn decreased significantly, whereas Tmin, Tmax and Pwv increased considerably. (2) In the BTH region, ET0 also exhibited a significant decreasing trend, and the sensitivity of ET0 to the climatic elements exhibited seasonal characteristics. Of all the climatic elements, ET0 was most sensitive to Pwv in the fall and winter and Rn in the spring and summer. On the annual scale, ET0 was most sensitive to Pwv, followed by Rn, Vw, Tmax and Tmin. In addition, the sensitivity coefficient of ET0 with respect to Pwv had a negative value for all the areas, indicating that increases in Pwv can prevent ET0 from increasing. (3) The sensitivity of ET0 to Tmin and Tmax was significantly lower than its sensitivity to other climatic elements. However, increases in temperature can lead to changes in Pwv and Rn. The temperature should be considered the key intrinsic climatic element that has caused the "evaporation paradox" phenomenon in the BTH region.  相似文献   

18.
正The Taal Volcano in Luzon is one of the most active and dangerous volcanoes of the Philippines. A recent eruption occurred on 12 January 2020(Fig. 1a), and this volcano is still active with the occurrence of volcanic earthquakes. The eruption has become a deep concern worldwide, not only for its damage on local society, but also for potential hazardous consequences on the Earth's climate and environment.  相似文献   

19.
The moving-window correlation analysis was applied to investigate the relationship between autumn Indian Ocean Dipole (IOD) events and the synchronous autumn precipitation in Huaxi region, based on the daily precipitation, sea surface temperature (SST) and atmospheric circulation data from 1960 to 2012. The correlation curves of IOD and the early modulation of Huaxi region’s autumn precipitation indicated a mutational site appeared in the 1970s. During 1960 to 1979, when the IOD was in positive phase in autumn, the circulations changed from a “W” shape to an ”M” shape at 500 hPa in Asia middle-high latitude region. Cold flux got into the Sichuan province with Northwest flow, the positive anomaly of the water vapor flux transported from Western Pacific to Huaxi region strengthened, caused precipitation increase in east Huaxi region. During 1980 to 1999, when the IOD in autumn was positive phase, the atmospheric circulation presented a “W” shape at 500 hPa, the positive anomaly of the water vapor flux transported from Bay of Bengal to Huaxi region strengthened, caused precipitation ascend in west Huaxi region. In summary, the Indian Ocean changed from cold phase to warm phase since the 1970s, caused the instability of the inter-annual relationship between the IOD and the autumn rainfall in Huaxi region.  相似文献   

20.
正While China’s Air Pollution Prevention and Control Action Plan on particulate matter since 2013 has reduced sulfate significantly, aerosol ammonium nitrate remains high in East China. As the high nitrate abundances are strongly linked with ammonia, reducing ammonia emissions is becoming increasingly important to improve the air quality of China. Although satellite data provide evidence of substantial increases in atmospheric ammonia concentrations over major agricultural regions, long-term surface observation of ammonia concentrations are sparse. In addition, there is still no consensus on  相似文献   

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