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1.
江苏省区域闪电分布特征 总被引：7，自引：2，他引：5
利用2006-2010年江苏省气象部门闪电定位系统的观测资料,对南京、苏州、徐州、南通和连云港5个代表性地区闪电频数的季节、月、日变化和空间分布特征以及闪电强度分布区间进行对比研究,探讨了各地闪电分布差异和全省闪电活动特征。结果表明,5个地区四季负闪均多于正闪;闪电频数年变化显著,南京峰值出现在7月,其他地区出现在8月;闪电日变化特征明显,各地区峰值出现在14：00—17：00。全省闪电频数的空间分布不均衡,苏南大于苏北和苏中地区,南京、镇江、常州部分地区分布着多个闪电密集中心。大部分闪电强度集中在20～50kA,100kA及以上的闪电很少,各地区正闪强度均高于负闪。 相似文献
2.
青藏铁路沿线区域闪电分布和闪电气候 总被引：2，自引：0，他引：2
用1998年1月1日～2003年12月31日TRMM卫星探测到的25～38°N,75～100°E闪电资料,对青藏高原地区年、季、日发生闪电频数和随经纬度变化,闪电密度分布的气候特征进行了计算分析。结果表明:青藏铁路沿线区域年均日发生闪电数约7 600次,白天占到66.47%,夜间占到33.53%,昼夜比为2.0,明显高于中国其它区域昼夜闪电比1.2。日闪电频数的年变化是多峰值,闪电主要发生在4～9月,占年总闪电的94.75%。5月上中旬和9月中下旬为次峰值,主峰值在夏季6～8月占到年总闪电70.23%,最高出现在7月占到年总闪电25.19%。10月到次年3月发生闪电很少,仅占年总闪电的5.25%,特别是11月到次年2月只占总闪电0.83%。青藏高原发生闪电的日变化以单峰值为主,年均达到346.75次/h左右,傍晚18时达到最高峰值,占到日出现闪电的12.1%,19～21时每小时达到日闪电值的9%以上,21～22时为快速下降时段,午夜24～01时出现维持时段,每小时达到日闪电值的3%,凌晨4～5时有小起伏,每小时达到日闪电值的1%,上午8～11时达到日变化的最低谷,4 h仅占日出现闪电的1.3%,闪电峰值是低谷的100倍以上,说明青藏高原区域闪电高发时间主要在傍晚。4个季节发生闪电峰值的日变化时间表明,不同季节出现闪电峰值的日时段不同,春季主要在晚间,夏季主要在傍晚,秋季主要在傍 相似文献
3.
利用TRMM卫星上携带的闪电探测仪（LIS）所获取的10 a闪电资料（1998—2007年）对西南地区闪电活动的时空分布特征进行了分析。结果表明：该地区闪电次数的年差异较大,最多年份是最少年份的2倍多,闪电活动季节性特征非常明显,闪电主要集中在春末仲夏发生,呈现单峰值特征,4—8月是闪电高发期（约占全年总闪电活动的84.83%）。闪电活动的日变化表明,闪电峰值区集中在傍晚、午夜前后两个时段,闪电谷值区出现在09：00—12：00,夜雷暴多,这是与其他地区闪电日变化显著不同的地方。在对闪电次数进行了探测效率订正后,根据LIS注视时间,计算了闪电密度。西南地区闪电密度分布大体呈现：东部高,西部低;南部高,北部低。闪电密度较高、面积较大的高值中心位于中越交界的老山一带,非常明显的大片低发区主要位于西南西部地区。研究表明：西南地区闪电时空分布与当地的地形地势、水汽和地理环境条件等诸多因素有关。 相似文献
4.
杨春明 《沙漠与绿洲气象(新疆气象)》2014,8(1):23-27
利用2006--2009年安徽省LD—II型闪电定位资料,对马鞍山地区闪电时空分布特征的分析表明,马鞍山地区以负闪为主,负闪占总闪电数的98％,平均闪电强度44．5kA。正负闪电发生的频次有明显的季节变化和日变化特征。闪电季节变化上呈单峰型,峰值出现在7月,集中发生在5—9月的雨季,占总闪电频次的97％;闪电日变化上呈双峰型,峰值出现在14：00和21：00。闪电强度冬季低、夏季高,多集中于20～30kA之间。平均地闪密度有两个明显的极大值中心,一个是穿越和县和含山中部的狭长带状区域,另一个集中在和县北部。平均闪电强度和平均地闪密度在空间上呈相反的分布形式。利用实测的地闪密度与雷暴日的关系得出了适用于马鞍山地区1市3县的地闪密度计算公式。 相似文献
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TRMM卫星观测到的华南地区的闪电时空分布特征 总被引：13，自引：7，他引：6
利用TRMM卫星上携带的闪电探测仪(LIS)所获取的9年闪电资料(1998—2006年)对华南地区闪电活动的时空分布特征进行了分析。该地区闪电次数的年差异较大,最多年份是最少年份的2倍多,闪电活动季节性特征非常明显,闪电主要集中发生在春末仲夏,呈现双峰值特征,4—8月是闪电高发期(约占全年总闪电活动的81.91%)。闪电活动的日变化表明,8月份闪电活动绝大多数发生在午后至傍晚时分,这也与对流活动相对应,5月份闪电活动除在午后有一个峰值区外,在凌晨也有一个不小的峰值区。华南地区的闪电密度高值区主要有：清远-广州一带、廉江市附近、海南岛中部,闪电密度低值区主要位于南海水面上。分析表明：华南地区闪电时空分布除与大尺度的天气系统背景有关外,还与太阳辐射、地形抬升、下垫面的性质等有关。太阳辐射的季节变化和日变化等是造成闪电时间分布的重要原因;地形的抬升作用和下垫面的性质及其差异是造成气候意义上中小尺度闪电空间分布差异的重要原因。 相似文献
6.
利用1998-2013年TRMM卫星上携带的闪电探测仪(LIS)监测的闪电资料以及云南6个气象站降水观测资料,分析云南闪电活动的时空分布特征及其与降水量的关系。结果表明:(1)云南地区平均闪电密度为4.7 fl·km^-2·a^-1,闪电密度分布与地形密切相关,自西北向东南呈"V"字型带状增大,滇南的西双版纳、普洱东南部和中越边境的闪电活动最为活跃,最高值为30.6 fl·km^-2·a^-1。(2)闪电活动具有明显的季节变化和日变化。春、夏季闪电活动明显多于秋、冬季,其中春季闪电活动主要发生在滇南,而夏季则在滇东。滇北闪电活动的月分布呈单峰型,峰值在7月或8月,且闪电密度与降水量有较好的相关性,而滇西、滇南和滇东南则呈双峰型,峰值在4月,次峰值在7月或8月,闪电密度与降水量的相关性较差。云南大部地区闪电易发生在当地时间16:00-20:00,而密度高值区的闪电活动多发生在夜间。(3)云南闪电活动明显受地形和海拔高度影响,且与季风密切相关。 相似文献
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中国区域闪电分布和闪电气候的特点 总被引：6，自引：0，他引：6
利用1998年1月1日到2003年12月31日TRMM卫星探测到18～38°N、74～123°E闪电资料,对中国区域年、季、日发生闪电频数和随经纬度变化,闪电密度分布和闪电气候特征进行了计算分析。结果表明:中国陆地区年均日发生总闪电数约54600次,白天占到54.47%,夜间占到45.53%,昼夜比为1.2。日闪电频数的年变化是双峰值,闪电主要发生在4～9月,占年总闪电的92%。4月中到5月中旬为次峰值,主峰值在7月中到8月中旬,占年总闪电的43.4%,夏季6～8月占到60%,11月到次年2月发生闪电很少,仅占年总闪电的0.4%以下。日变化以单峰值为主,峰值范围宽,年均每小时达到2275次左右,傍晚18时达到最高峰值,占到日出现闪电的9.1%,上午9～11时达到日变化的最低谷,仅占日出现闪电总的3%,闪电峰值是低谷的12倍,说明中国区域闪电高发时间主要在傍晚。中国区域年均发生闪电频数随纬度的变化要比随经度的变化大,沿海的陆地区出现闪电频数比内陆区高,内陆区比海区高,东部比西部高的特点。4个季节发生闪电峰值的日变化时间表明,不同季节出现闪电峰值的日时段不同,冬季主要在中午,秋季主要在下午,春季主要在晚间,夏季主要在傍晚。中国区域年均白天、夜间和昼夜不同闪电密度分布表明,东部比西部高,闪电高密度区相对较集中。区域对比说明,白天发生闪电 相似文献
9.
张家口市闪电活动与大气湿度响应关系 总被引：1，自引：0，他引：1
水汽条件是产生雷电活动的一个必不可少的气象要素。利用河北省闪电定位系统监测的2011—2013年全省地闪资料和NCEP/NCAR再分析相对湿度资料,对张家口市的闪电活动特征及其与相对湿度垂直结构特征的响应关系进行了分析。结果表明：①张家口市闪电时间分布与全省闪电分布走势基本一致,夏季闪电活动最强烈;逐月演变不均匀且日分布呈单峰单谷型变化特征,张家口市日闪电峰值和谷值分别出现在17:00—18:00与01:00—09:00。②闪电活动与相对湿度垂直结构特征响应关系特征明显：闪电活动时低层湿度不高、中层较湿、高层偏干,大约在中层700 hPa以下相对湿度随高度增加,中层以上相对湿度又随高度减小。③张家口市闪电活动时大气相对湿度垂直结构本地化特征：850 hPa以下相对湿度保持在40%～60%,中层600～700 hPa之间相对湿度一般升至60%～80%,且闪电强烈程度与中层湿层厚度正相关,高层200～400 hPa左右相对湿度降低至20%～40%。 相似文献
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利用河南省气象部门提供的ADTD雷电探测系统2006-2010年的闪电资料,分析了河南地区云地闪电的月变化、日变化及闪电密度和闪电强度时空分布特征.结果表明:河南省云地闪中负闪占绝大多数,占总闪电的96.54％,但正闪平均强度比负闪大.闪电密度大的地区集中在山区和平原过渡区及河网密集、水域分布较广的地区.地闪主要出现在夏季,占全年的91.50％;气温较高的季节里,正闪占闪电总数百分率较低,反之较高.闪电的发生有明显的日变化,集中在13-24时,最大值出现在17时.正、负闪电的强度主要集中在10～60 kA,大于100 kA的闪电主要分布于豫西、豫南和豫东部分地区,且闪电强度较大的地区,闪电密度较小. 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
12.
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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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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《大气和海洋科学快报》2013,(4):227
正AIMS AND SCOPE Atmospheric and Oceanic Science Letters (AOSL) publishes short research letters on all disciplines of the atmosphere sciences and physical oceanography. 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
18.
《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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《大气科学进展》2014,(6)
正Aims Scope Advances in Atmospheric Sciences(AAS)is an international journal on the dynamics,physics,and chemistry of the atmosphere and ocean with papers across the full range of the atmospheric sciences,co-published bimonthly by Science Press and Springer.The journal includes Articles,Note and Correspondence,and Letters.Contributions from all over the world are welcome. 相似文献