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1.
广州市番禺区高温天气与热带气旋关系   总被引:3,自引:0,他引:3  
朱建军  杨宏建  余海军 《气象》2006,32(6):66-70
利用番禺区1960—2004年高温天气(Tmax≥35℃)的历史资料及同期热带气旋资料,采用统计方法研究高温天气与热带气旋影响区(15~35°N、110~135°E)内热带气旋之间的关系,得出:(1)高温特别是36℃以上高温与热带气旋有着密切的关系,高温强度越强,存在强热带风暴和台风的比例也越大。没有热带气旋存在仅靠副热带高压作用,则出现36℃以上高温的机会小得多,并且没有37℃以上超高温天气出现;(2)西北太平洋源地热带气旋对高温的贡献较南海源地占有绝对优势。无论何种源地,从热带低压到强热带风暴,随着热带气旋强度的增强,出现高温的比例都有一个明显的突跃;(3)7—9月份出现高温时,热带气旋存在的比例在68%~87%之间。移经热带气旋影响区的热带气旋,以7月出现高温的比率为最大,强热带风暴以上出现高温比例超过35%。  相似文献   

2.
对珠海市1962~2006年高温资料进行统计分析,对高温日天气过程进行普查,发现副热带高压和热带气旋是导致珠海市高温的主要天气系统。分析发现导致高温天气的系统可以分为三种类型,热带气旋型在三种类型中占比较大的比例,热带气旋和副热带高压共同影响型会导致珠海出现极端高温。  相似文献   

3.
热带气旋外围环流和广州灾害性高温关系的研究   总被引:5,自引:3,他引:5  
卢山  叶萌 《热带气象学报》2006,22(5):461-465
利用1983-2004年6-9月常规天气资料、广州单站数据和此期间热带气旋年鉴资料、NCEP/NCAR再分析资料,并定义连续3天或以上日最高气温≥35℃为一次灾害性高温天气过程,对广州灾害性高温天气和热带气旋活动的关系进行了分析,结果发现:(1)广州市的灾害性高温天气的出现和热带气旋外围环流紧密相关,且37℃以上的灾害性高温天气主要出现在广州市东南或偏东方向400—1600km范围内的洋面或海面有热带气旋活动时;(2)副热带高压控制下的强烈太阳辐射是广州灾害性高温出现的基础,而热带气旋外围下沉气流导致的强下沉增温是重要因素。  相似文献   

4.
涂建文  许连丰 《广西气象》2007,28(A02):35-35,44
对珠海市1962-2006年高温资料进行统计分析,对高温日天气过程进行普查,发现副热带高压和热带气旋是导致珠海市高温的主要天气系统。分析发现导致高温天气的系统可以分为三种类型,热带气旋型在三种类型中占比较大的比例,热带气旋和副热带高压共同影响型会导致珠海出现极端高温。  相似文献   

5.
利用南沙气象探测基地的地面常规观测资料对南沙的高温日进行了统计,并对2012年7-8月的高温天气过程做了分析,结果发现:南沙高温日数和持续高温出现最多的是2009年,持续高温以2d最多,持续时间最长的为3d;南沙高温主要在6-9月出现,集中出现在7月下旬-8月下旬,高温日出现最多的是8月;高温一般出现在15:00前后.2012年高温出现时副高一般断裂成块状或者脊线比较偏北,受热带气旋的影响较大;所有的高温日都受热带气旋外围下沉气流影响;当热带气旋位于南沙区偏东时,出现高温持续的时间较长,而且过程最高气温也较高.高温日当天08:00气温高、云量偏少、地面风速低、以西到西北风为主,湿度偏低.  相似文献   

6.
此文用21年(1957-1977)的北太平洋探空资料,研究了大尺度天气型与热带气旋转向前和转向期间的环境场相互作用的问题。这是首次对对流层各层环境风场与热带气旋转向前和转向期间的关系所进行的定量研究。结果发现,热带气旋转向前1-2天,气旋北方、西北方对流层高层的纬向风场有明显的变化。气旋的转向,实际上是当正纬向风在距气旋中心6°时穿入中高对流层开始转向的。如在这个半径出现负纬向风就不会转向。  相似文献   

7.
基于北海市气象局承担的项目<制作影响北部湾地区热带气旋历史资料库>,对库中收录1954~2002年的所有进入18°~23°N,105°~112°E范围,且中心附近最大风力达8级或以上的共计128个热带气旋的天气气候特征进行初步的统计和分析,同时对该资料库系统的各种分类功能进行简单介绍.为今后的热带气旋预报和研究工作提供一个资料平台.  相似文献   

8.
登陆广东热带气旋特征及其与副热带高压的关系   总被引:4,自引:1,他引:3  
2004年登陆广东的热带气旋只有2个,个数明显偏少,粤西无热带气旋登陆;登陆广东的初台偏迟,终台结束早,登陆时间集中于7月;热带气旋移速快,强度弱(为热带风暴),对广东影响利大于弊。对1951~2004年7~9月登陆广东的热带气旋进行统计分析,发现各月登陆广东的热带气旋次数差异较大,最多时一个月有5个,最少时没有。登陆广东的热带气旋个数与西北太平洋副热带高压位置、强度有密切关系,可以将有利于和不利于热带气旋登陆广东的副热带高压各分为3种环流形势。  相似文献   

9.
江门地区夏季高温的成因   总被引:5,自引:35,他引:5  
通过对江门地区1961~2005年高温资料的统计分析,揭示江门地区高温天气的时空变化,并探讨造成高温天气的主要天气系统及形势特征。结果表明:江门地区夏季高温出现频率在增加,持续性高温也呈增长状态;高温结束时间出现标志性后跃;造成江门夏季高温的主要天气形势是强盛的副热带高压稳定控制和热带气旋逼近时的外围下沉气流。此外,城市“热岛效应”对高温天气也有增强作用。  相似文献   

10.
本文根据GMS气象卫星1—3小时红外分层云图和有关气象资料,给1984—1988年6—9月位于32°N以南、126°E以西,中心附近最大风力8级以上的热带气旋边缘区域发生强对流天气的中尺度强风暴云团以客观定义,并对其特点、结构、移动、天气及天气形势条件进行分析研究,发现一些有意义的事实。  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.
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   

14.
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   

15.
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   

16.
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   

17.
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   

18.
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   

19.
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   

20.
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   

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