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1.
海南省澄迈县雷暴气候特征及其灾害防御 总被引：5，自引：1，他引：5
通过统计分析海南省澄迈县1959~2004年逐日雷暴资料,找出雷暴发生时空分布特征,统计1995~2004年10a雷暴发生的影响天气系统,计算出各天气系统影响下雷暴发生的概率。分析结果表明:澄迈县雷暴日46a平均雷暴频次437次,年际变化呈波动减少趋势,5~8月是雷暴发生的高发期,占全年雷暴的53%,16~17时是一天中发生雷暴的最高期,西南方向发生的雷暴略多于其他方向,澄迈县受西南低压槽、南海低压槽和副热带高压等天气系统影响时发生雷暴的概率较大。 相似文献
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《干旱气象》2015,(4)
雷暴天气是甘肃武威市多发的灾害性天气之一。利用1961~2010年武威市5个气象站雷暴资料,以及2001~2010年4~10月逐日NCEP再分析资料,分析了武威市雷暴天气的时空分布特征及变化趋势,并依据气流的南北配置方法对雷暴天气进行了环流分型。结果表明:受海拔高度和地形地势的影响,武威市雷暴具有明显的地域特征,南部天祝山区雷暴日数远大于其他各地,占雷暴总日数的40.6%。年际、年代际雷暴日数总体呈减少趋势,其中,天祝的减少趋势尤为显著,其递减率为-5.819 d/10 a,年雷暴日数的时间序列存在着7~8 a的准周期变化。一年内,6~8月是雷暴的高发期,雷暴日数占全年总日数的70.8%~78.6%。雷暴的日变化特征明显,12~22时为其多发时段,集中发生时段为13~17时,雷暴的平均持续时间为10~40 min。武威市雷暴天气环流形势可分为西北气流型、西南气流型和西风气流型3类。其中,西北气流型,高空冷平流深厚且移速缓慢,最有利于强对流天气发生,雷暴发生比例最高;西南气流型,系统过境后无残余的冷空气滞留,不利于强对流天气发生,雷暴发生比例最低;西风气流型,高空低涡位置较偏北,冷空气较强,较利于强对流天气发生,雷暴发生比例相对较高。 相似文献
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《气象科学进展》2021,(4)
采用2010—2018年的海南岛天气分型资料和闪电定位数据,统计分析海南岛在西南低压槽影响下地闪发生概率的时空分布特征,结果显示:在西南低压槽天气影响下,海南岛地闪主要出现在4—9月;地闪发生概率月分布曲线呈双峰特性,以8月为主峰、5月为次峰,00—12时(北京时,下同)的地闪发生概率月分布曲线与全天不同,呈逐月上升特征;地闪发生概率和地闪次数时段分布曲线呈单峰特性,峰值均出现在15—18时,除12—21时外其他时段的地闪发生概率和地闪次数都很低,控制过程的后期比前期的闪发生概率和地闪次数略高;00—12时各时段海南岛地闪发生概率中心分布在东南沿海,概率中心值在5%以下,12—21时各时段地闪发生概率中心分布在北部内陆,概率中心由白沙中部向澄迈东部移动,移向呈西南—东北向,15—18时概率中心在澄迈南部达到最大值40%,21时以后概率中心分布在屯昌境内,中心值在5%以下;7—9月各时段的地闪发生概率均比4—6月高,但地闪次数峰值比4—6月少,两者各时段的地闪发生概率的空间分布完全一致。 相似文献
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以海南文昌为例,通过对影响海南省的四类十二型天气系统的活动及其对降水天气的影响进行分析研究表明,影响海南省的天气系统,以热带系统较多,冷空气类系统次之;单一系统,以变暖高压脊(G2)和西南低压槽(SWT)较活跃,华南沿海槽(ST2)和越南低压槽(YT)较少。降水则以冷空气类(除WS型)和低压槽类(除SWT型)较多,降水概率基本在50%以上,其中静止锋(WQ,EQ)系统和华南沿海槽(ST2)的降水概率甚至达到65~70%;较好地揭示了各种天气系统在海南省的活动规律及与降水的关系,为海南省指导各县市的天气预报及服务提供依据。 相似文献
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2006年5—9月雷暴天气及各种物理量指数的统计分析 总被引：2，自引：0，他引：2
对2006年5-9月全国雷暴天气时空特征进行了统计分析,结果表明:雷暴天气的发生具有明显的短时局地特征,大多数发生在17-20时,上午11时发生最少.全国范围发生过雷暴天气的站点不到总数的三分之一.从空间分布来看,广东、广西及云南三省(区)是雷暴发生最为频繁的省份,内蒙古中西部、新疆北部、青海北部等地则发生较少.此外,统计分析各物理量指数后发现,各种物理量指数对于雷暴等强对流天气发生呈现出不同的概率分布特征,其中最主要的特征是当雷暴等强对流性天气发生时,存在3个高概率区域,每个区域对应物理量指数值相对集中在一个特定范围内. 相似文献
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利用海南岛区域加密自动站资料和海口站探空资料,结合ERA-Interim再分析资料对2014-2018年海南岛雷暴大风的强度、时空分布、环流形势和物理量参数特征进行分析研究。结果表明:(1)海南岛雷暴大风主要出现在5-8月的午后到傍晚时段,最大阵风风速大部分在8级及以上。(2)雷暴大风的环流形势可以分为三类,即西南热低压型、季风槽型和冷锋型,其中季风槽型根据槽线位置可以分为华南沿海槽型和南海低压槽型。(3)西南热低压型雷暴大风的大气不稳定能量最大,上干下湿,垂直风切变较小;冷锋型的大气不稳定能量最小,上干下湿,垂直风切变最大;季风槽型的大气不稳定能量较大,整层较湿,垂直风切变最小。(4)季风槽天气形势下发生雷暴大风时,较容易伴随短时强降水天气,西南热低压型的雷暴大风风力比其他类型更大。 相似文献
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博州雷暴的时间变化和周期 总被引：4，自引：0，他引：4
利用1961--2000年博州4个气象站雷暴天气的观测资料,分析了雷暴的气候特征.分析表明,博州多年年雷暴日数20-52d,年雷暴日数平原地区较少,高山地区较多,雷暴天气集中出现在夏半年5-8月.温泉雷暴天气的高发时段15-21时,精河高发时段17-23时,阿拉山口高发时段16-24时.温泉、精河和阿拉山口雷暴持续时间以30min为主.博乐和阿拉山口40a内年雷暴日数线性减少,两站年雷暴日数在1979年发生突变.博州雷暴日数年际变化具有6～9a的震荡周期. 相似文献
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河北廊坊雷暴大风的气候特征 总被引：1，自引：0，他引：1
利用1970~2012年廊坊地区9个气象站地面雷暴大风观测资料,采用趋势分析、滑动t检验、小波分析和最大熵谱分析等统计方法,系统分析了该地区雷暴大风天气的时空特征及变化趋势和变化周期。结果表明:廊坊地区的雷暴大风局地性强,43 a间只出现了一次全区性的雷暴大风天气过程,雷暴大风多以单站出现为主。雷暴大风的地域性特征明显,中部的廊坊市及南部的文安、大城站较易出现,而北部发生概率较低。雷暴大风的日、月及年变化特征明显。雷暴与大风主要发生在午后至前半夜,大风发生时间一般落后于雷暴,1 h内的雷暴与10 min以内的大风发生概率最高;雷暴大风3~10月都可出现,主要集中在夏季,发生概率为73.3%;近43 a来,年均雷暴大风日数整体呈现减少趋势,且中部的站点减少趋势最显著,1994年为雷暴大风的显著突变年,其显著变化周期为3.23a。雷暴大风多为"湿"型。 相似文献
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利用常规观测资料、多普勒天气雷达、自动气象站等资料对2004年7月12日影响上海的一次较长生命史的强飑线过程进行了综合分析，对这次强对流天气发生、发展、强度以及移动和传播的分析结果表明:副热带高压从华南沿海稳定地加强西伸，西风槽缓慢东移，导致华东地区850~500 hPa形成深厚西南急流，急流的加强促使低层锋生，配合K指数高能锋区的不稳定层结，大大增强了强对流天气发生的可能性；地面锋生作用和低层辐合、高层辐散造成的强抬升作用是主要的触发机制；较强的环境风垂直切变和雷暴内部上升气流与下沉气流的正反馈作用是飑线系统维持较长时间的原因，中尺度对流系统(MCS)多个雷暴单体间的相互作用使得南侧的雷暴单体加强、移动方向发生偏转。 相似文献
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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
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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
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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
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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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Yuepeng PAN Mengna GU Yuexin HE Dianming WU Chunyan LIU Linlin SONG Shili TIAN Xuemei Lü Yang SUN Tao SONG Wendell W. WALTERS Xuejun LIU Nicholas A. MARTIN Qianqian ZHANG Yunting FANG Valerio FERRACCI Yuesi WANG 《大气科学进展》2020,37(9):933-938
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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《大气和海洋科学快报》2013,(1):67
正AIMS AND SCOPE Atmospheric and Oceanic Science Letters (AOSL) publishes short research letters on all disciplines of the atmosphere sciences and physical oceanography. Contributions from all over the world are welcome.SUBMISSIONAll submitted 相似文献
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<正>With the support of specialized funds for national science institutions,the Guangzhou Institute of Tropical and Marine Meteorology,China Meteorological Administration set up in October 2008 an experiment base for marine meteorology and a number of observation systems for the coastal boundary layer,air-sea flux,marine environmental elements,and basic meteorological elements at Bohe town,Maoming city,Guangdong province,in the northern part of the South China Sea. 相似文献
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《大气和海洋科学快报》2014,7(6):F0003-F0003
AIMS AND SCOPE
Atmospheric and Oceanic Science Letters （AOSL） publishes short research letters on all disciplines of the atmosphere sciences and physical oceanography. Contributions from all over the world are welcome. 相似文献
Atmospheric and Oceanic Science Letters （AOSL） publishes short research letters on all disciplines of the atmosphere sciences and physical oceanography. Contributions from all over the world are welcome. 相似文献
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《大气和海洋科学快报》2014,(5):F0003-F0003
AIMS AND SCOPE Atmospheric and Oceanic Science Letters （AOSL） pub- lishes short research letters on all disciplines of the atmos- phere sciences and physical oceanography. Contributions from all over the world are welcome. 相似文献