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利用常规气象资料、NCEP/NCAR再分析资料,对2012年春季肇庆“回南天”天气形势特征和气象要素进行统计和天气学原理分析,结果发现:温度露点差和露点温度曲线的交点出现在“回南天”发生前的第2到4天,对“回南天”预报具有一定作用的时间提前量;“回南天”期间环流形势为:500 hPa东槽槽底偏北,南支波动活跃,850 hPa华南地区西南风风速明显加大至6～8 m/s,肇庆位于高湿区和水汽通量梯度最大的地方;在“回南天”前期及期间,大气中低层大部分时间出现逆温层,主要集中在850 ～ 925 hPa. 相似文献
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利用NCEP/NCAR的25°×25°格点再分析资料以及南宁站气温、露点、能见度、气压等常规观测资料与河池、北海站探空资料,采用统计分析和典型个例分析相结合的方法,分析了2005—2013年广西“回南天”过程的天气形势和气象要素特征。结果发现：①不同影响程度“回南天”发生前均受到较长时间的冷空气影响;②“回南天”发生时,地面有暖低压或倒槽发展,中高纬度没有明显的冷空气南下,850 hPa和925 hPa上南风强盛,锋区逆温接近近地层,温度骤升,气压剧降,湿度加大,当日14:00露点温度高于当日最低气温;③“回南天”结束方式有两种：冷性结束和暖性结束;④“回南天”预报依据：如果广西冬春季在较长时间的冷空气影响之后,925 hPa温度和湿度突增,同时预测到未来1~2天,14:00露点温度将高于当天最低温度。 相似文献
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利用NCEP/NCAR再分析资料和北部湾地区5站地面观测资料,对比分析了3次典型大雾过程的环流背景和气象要素特征。结果表明:(1)平流雾维持时间最长、强度最强,辐射雾发生范围最广,锋面雾发生范围最小、持续时间最短;(2)锋面雾和平流雾500hPa有较明显的南支槽,副高偏强,850hPa偏南风偏强,因冷空气入侵或冷空气减弱东移与暖湿气流相遇而成雾,辐射雾过程无冷空气直接影响,因夜间辐射冷却而成雾;(3)辐射雾过程气温与能见度呈同相变化特征,露点温度呈逐日上升趋势,锋面雾前期和后期气温、露点温度与能见度分别呈反相和同相变化特征,平流雾过程气温、露点温度呈逐日升高趋势,能见度具有较明显日变化特征;(4)辐射雾和锋面雾发生时相对湿度≥93%,偏南风和偏北风风速减小;平流雾期间相对湿度持续≥90%,风速由弱偏北风转偏南风。 相似文献
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利用地面观测资料和MICAPS资料,分析了泰安3次秋季强降雪产生的天气形势、物理量及其演变特征,同时对欧洲中心数值预报的温度预报进行了检验。结果表明:泰安秋季强降雪发生的天气形势均为回流形势;雨雪转化时850hPa均有东南气流建立,当850hPa东南气流转为北西北气流、925hPa东北气流转为西北气流控制时,降雪趋于结束;强降雪发生时850~400hPa均有较强的上升运动,水汽辐合中心在800~850hPa;雨雪相变基本发生在08时和20时前后,欧洲中心数值预报850hPa温度预报≤-2℃可作为泰安秋季雨(雨夹雪)转为雪的温度指标。 相似文献
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通过理论假设推导出建筑物内壁温度与气温及15CM地温的关系式,利用历史“回南天”过程记录确定了关系式的相关系数,建立了建筑物内壁温度的拟合公式,有效的解决了长期以来困扰“回南天”观测资料缺少的难题;通过聚类分析,研究“回南天”主要天气影响系统及特征,结果表明南宁市“回南天”过程是在冷高压和暖低压的交替影响下产生,分为冷性结束和暖性结束两类过程,并总结两类过程的单站内壁温度、气温、露点、24小时日平均变压等要素变化特征和天气形势场特征,分析它们与“回南”影响时间及强度的关系,得出冷性结束“回南天”过程,“回南”持续时间长,强度强,出现频率高的结论. 相似文献
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采用小波分析、Lanczos时间滤波器、合成分析等方法分析了2011年夏季广东季风槽暴雨与大气低频振荡的关系。结果表明,2011年夏季降水主要存在准20 d的周期振荡,季风槽暴雨过程对应强的准双周振荡。选取与夏季降水显著相关的区域（102.5~117.5 °E,20~27.5 °N）平均的500 hPa高度场作为影响广东夏季降水的“500 hPa关键区”指数,同样选取区域（110~120 °E,15~22.5 °N）平均的850 hPa风场作为“850 hPa关键区”指数;2011年夏季500 hPa关键区与850 hPa关键区分别存在显著的准23 d、准22 d周期振荡,季风槽暴雨发生在500 hPa关键区准双周振荡的波谷、850 hPa关键区准双周振荡的波峰附近。从南海南部开始的3次低频纬向风、OLR、湿度的北传与从菲律宾以东的西太平洋向西传播的低频中心相遇,导致3次季风槽暴雨过程。利用典型个例的合成分析,对2011年6—8月广东3次季风槽暴雨的准双周振荡不同位相的大气环流场的共同演变特征进行分析,它们反映了季风槽暴雨从间歇-开始-旺盛-减弱-结束期的大气环流场演变特征,为广东季风槽暴雨的中期预报提供参考依据。 相似文献
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2004年入冬后清远市首次低温霜冻分析 总被引：6，自引：4，他引：2
本文通过分析2004年12月5～14日清远市北部地区出现的大面积连续低温霜冻天气,发现低温的出现与850hPa的负变高和露点温度有一定的对应关系,霜冻出现和结束与环流形势密切相关。 相似文献
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利用常规观测资料、加密地面自动站、闪电定位仪和ERA5再分析资料,将2011—2020年湖北冷季91次高架雷暴事件,按照形成机制分为雷雨型、强对流型和雷打雪型3类,并细致归纳了3类事件的时空分布特征、大气环流背景及关键环境参数等特征。(1) 湖北冷季高架雷暴雷雨型最多,强对流型次之,雷打雪型最少。3类型存在明显的时空分布差异,雷雨型主要发生在秋末冬初(11月)和冬末初春(1—2月),强对流型及雷打雪型常出现在早春2月,3月基本以强对流型为主。(2) 低槽冷锋、850 hPa切变线及低空西南急流是冷季高架雷暴发生的有利环流背景,近地面为稳定的冷气团控制,逆温明显,西南低空急流沿着锋面逆温层以上的850 hPa附近触发抬升,水汽、上升运动及不稳定层结均出现在850 hPa以上。雷雨型和雷打雪型距离冷锋超过100 km以上,强对流型不足100 km。(3) 850 hPa是风场转换的重要层次。强对流型850 hPa露点温度(Td850)、K指数、850 hPa与 500 hPa温差(ΔT85)、850 hPa假相当位温(θse850)、西南急流厚度和强度(I700)、切变线强度(S850)最大,中低层(850~700 hPa)垂直风切变(SL78)最小;雷打雪型对水汽和不稳定能量的要求最低,SL78最大。 相似文献
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孙洪伟张宇张鑫王京京 《黑龙江气象》2022,(3):8-11
选取2020年8月27-28日黑龙江省降雨量和风的实况观测资料以及NCEP再分析等资料,分析了2020年“巴威”台风影响黑龙江省时的风雨天气实况、环流形势和物理量场特征。结果表明:“巴威”台风登陆后迅速减弱变性,对黑龙江省的影响主要是暴雨天气,风力影响相对较小。台风减弱变性后的温带气旋以及低层850 hPa和700 hPa风向或风速辐合为产生暴雨提供了较好的动力抬升条件,台风携带水汽及低空急流的水汽输送为产生暴雨提供了充分的水汽条件,低层风场辐合区稳定少动为产生暴雨提供了充足的时间。低层850 hPa比湿、水汽通量、水汽通量散度以及中低层垂直速度等物理量要素对预报暴雨落区和发生时间有较好的指示意义。 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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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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《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
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《大气和海洋科学快报》2012,(3):273
正AIMS AND SCOPE Atmospheric and Oceanic Science Letters (AOSL) publishes short research letters on all disciplines of the atmosphere sciences 相似文献