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1.
利用西南区域11个探空站数据及地面常规观测资料,对2010~2020年196次暴雨过程中表征水汽、热力不稳定、动力条件的10种物理量参数进行统计分析,基于箱线图提取了一些有利于暴雨发生的环境参数阈值。结果表明:(1)对流层中低层近饱和的大气和比湿高值是该区域暴雨发生的有利条件之一;(2)沙氏指数在各季节的阈值均较低,对流有效位能在盛夏时值较高,多对流性暴雨,而初秋对其要求不高,多稳定性暴雨;(3)初夏和盛夏对最大上升速度的要求明显大于初秋,而能量螺旋度主要在初夏才有一定要求。  相似文献   

2.
分析了NCEP资料和SAMIL-R42L9中热带大气季节内(30~60天)振荡(ISO)的季节变化特征及其与平均气候场季节变化的关系。NCEP资料的分析表明:热带地区大气ISO在空间分布上存在明显的季节变化,大气ISO的季节变化与平均背景场的季节变化有明显的一致性。在空间分布上,热带大气ISO的活动对暖的SST、强的对流活动、西风、强的降水和低层水汽辐合有很强的依赖性。大气环流模式SAMIL-R42L9基本能够再现热带大气ISO空间分布上的季节转换特征,尤其在动力场(纬向风)上表现得最为明显。但对基本气候态季节变化的模拟,对不同的物理量有明显的差异。模式结果表明:热带大气ISO动力因子的季节性比热力因子的季节性对平均背景场的依赖性更大,模式不能很好地反映NCEP资料表现出来的ISO对平均背景场的强依赖性,同时也说明热带大气ISO的季节性可能并不完全依赖于平均背景场的季节变化。  相似文献   

3.
为提高黔南冰雹预报预警能力,利用黔南州1999-2021年12个县市气象站冰雹资料及贵阳探空资料,对115次冰雹天气过程中表征不稳定、水汽、热力、动力条件的19个物理量参数特征进行统计分析,并提取黔南地区发生冰雹的物理量阈值。结果表明:冰雹发生前,贵阳探空站的物理量在合适的范围时,黔南州出现冰雹的可能性较大;不同季节冰雹发生前的各物理量存在差异,秋冬季节动力条件表现明显,而春夏季节水汽、热力、层结稳定度条件更为显著;逆温层的出现对中低层温度、温度垂直递减率、低层水汽条件均有明显的影响,从而影响部分物理量的强弱,故本文按照有无逆温给出2-5月黔南冰雹天气的物理量阈值。  相似文献   

4.
本文通过对江西19次区域暴雨过程的物理量合成分析,得出江西产生区域暴雨物理背景场的热力条件和动力条件,归纳出江西区域强暴雨的预报着眼点.  相似文献   

5.
2010年春季河南一次区域性暴雨天气分析   总被引:2,自引:0,他引:2  
2010年4月20日08时11日08时河南出现了一次区域性暴雨天气。对本次过程的高低空天气形势、卫星资料、雷达产品、NCEP再分析物理量等资料的分析结果表明:这次区域性暴雨是在高空低槽和切变线的作用下,由中低层强盛的西南暖湿气流和低空东风急流,以及地面倒槽的共同影响下产生的。由于影响系统比较稳定,移动速度较慢,且无明显不稳定能量存在,因此为一次稳定性的降水天气过程,与夏季的对流性短时强降水有明显的不同。卫星云图和雷达产品资料显示,云系的发展和移动与低槽和切变线配合较好,主要以层状云系为主,小时雨强并不大,对此次过程预报分析有很好的补充作用。对水汽、热力和动力因子等物理量的分析发现:在降水发生前,水汽条件已较好,丰富的水汽输送和持续的水汽积聚有利于降水的持续;深厚而强烈的垂直上升运动以及上层辐散、下层辐合的抽吸耦合作用,为暴雨的形成和维持提供了充足的动力条件;较长的降水持续时间,为暴雨的形成提供了充足的条件。  相似文献   

6.
江西区域强暴雨的热力和动力条件诊断分析   总被引:3,自引:1,他引:3  
曹晓岗  王田民  尹洁  戴熙敏 《气象》1996,22(4):37-40
通过对江西19次强暴雨过程的物理量合成分析,得出江西产生强暴雨物理背景场的热力 动力条件,归纳出江西区域强暴雨的预报着眼点。  相似文献   

7.
利用气象观测资料和NCEP再分析资料对梅汛期江淮切变线暴雨类个例与切变线非暴雨类个例演变过程进行了合成对比分析。结果表明,形成暴雨切变线的演变历程中,存在南北风加强,切变线发展,且西南风急流引起的风速辐合加强了低空辐合。同时江苏处于高空急流入口区的右侧,高低空急流相耦合,形成了高空辐散、低空辐合的动力机制,降水过程中动力结构配置的演变特征十分鲜明。切变线南侧热力不稳定条件较好,水汽输送丰富,水汽辐合强烈,这些都有利于暴雨中尺度系统的发生、发展。因为动力、热力条件强度的不同对应不同强度的降水,区域性大暴雨的动力系统比一般暴雨更深厚,不稳定条件更强,水汽输送也更充沛。而切变线非暴雨类中,高低空风场的配置不利于降水的增强。南北风增强不明显,切变线不能得到发展,同时其南侧西南风急流没有建立,风速辐合较弱。高空急流核远离江苏,江苏上空的辐散场很弱,高空辐散、低空辐合的动力机制未能建立,动力结构的配置演变特征不明显。切变线南侧的热力不稳定度也不如暴雨类强,水汽的辐合较弱,不利于中尺度系统的发生、发展。  相似文献   

8.
利用常规地面与高空观测资料、自动站逐时资料、NECP1°×1°再分析资料,对阿克苏地区2015年9月7日局地暴雨进行分析。结果表明,此次暴雨的主要成因有:(1)100hPa南亚高压双体型、200 hPa高空急流以及500 h Pa中亚槽提供了有利的环流背景,"三支气流"配合加强了动力以及热力条件并促使水汽快速汇集,强度为8 g·cm~(-1)·hPa~(-1)·s~(-1);(2)暴雨过程的大部分水汽是通过低层偏东气流接力输送,水汽的来源主要为南海及孟加拉湾;(3)暴雨发生前阿克苏处于高能高湿不稳定区域,存在315.9 J·kg~(-1)的不稳定能量,水汽上干下湿体现了一定的对流特征,同时锋区、垂直风切变、湿层以及不稳定能量的突变预示了强对流天气的发生;(4)低层风场辐合触发对流,地面辐合线及偏东风输送位置影响暴雨落区,加之较好的地面热力条件以及独特的地形增益暴雨强度。  相似文献   

9.
利用NCEP FNLs分析资料,针对2012年7月23日、2013年7月2日下午至夜间发生在西太平洋副热带高压(副高)边缘附近暖区的对流雨带,从动力、水汽、热力和不稳定度等方面分析其产生原因,发现副高存在明显的动力、热力和对流不稳定度边界,对流雨带发生在副高的边界附近。研究结果表明,副高动力边界内部为大范围下沉运动,动力边界外侧存在弱的垂直上升运动;水汽和热力边界内部为高温、高湿,外部则相对干冷;在对流不稳定边界内部,对流不稳定层较深厚,而外部则较浅薄。在副高动力边界的外侧,水汽、热力及对流不稳定边界的内侧附近,有利的水汽条件、对流不稳定条件和动力抬升条件,使得这里容易产生对流活动,形成对流雨带。副高的动力、水汽、热力及对流不稳定度边界,对应了边界附近对流雨带的发展,相比传统的副高标志线,其物理意义更加明确,对暖区对流的预报更具指示意义。  相似文献   

10.
利用常规气象资料、物理量场资料和雷达卫星等资料,从大尺度环流背景、降水天气影响系统、物理量场、急流等方面,分析了2009年7月8—9日发生在山东省的一次区域性暴雨的成因。结果表明,强降水是西风槽与低涡切变线和地面气旋共同影响造成的,低空急流是主要的水汽输送通道,为暴雨产生提供了水汽条件。高低空急流相距越近,其耦合作用越明显,对流发展越旺盛,降水越强。暴雨落区与水汽、涡度、层结稳定度指数等环境物理量有较好的对应关系。暴雨落区变化与低涡移动路径基本一致,后期跟地面气旋移动路径基本一致。  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.
<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   

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.
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   

15.
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   

16.
基于最新的GTAP8 (Global Trade Analysis Project)数据库,使用投入产出法,分析了2004年到2007年全球贸易变化下南北集团贸易隐含碳变化及对全球碳排放的影响。结果显示,随着发展中国家进出口规模扩张,全球贸易隐含碳流向的重心逐渐向发展中国家转移。2004年到2007年,发达国家高端设备制造业和服务业出口以及发展中国家资源、能源密集型行业及中低端制造业出口的趋势加强,该过程的生产转移导致全球碳排放增长4.15亿t,占研究时段全球贸易隐含碳增量的63%。未来发展中国家的出口隐含碳比重还将进一步提高。贸易变化带来的南北集团隐含碳流动变化对全球应对气候变化行动的影响日益突出,发达国家对此负有重要责任。  相似文献   

17.
正ERRATUM to: Atmospheric and Oceanic Science Letters, 4(2011), 124-130 On page 126 of the printed edition (Issue 2, Volume 4), Fig. 2 was a wrong figure because the contact author made mistake giving the wrong one. The corrected edition has been updated on our website. The editorial office is sincerely sorry for any  相似文献   

18.
19.
Index to Vol.31     
正AN Junling;see LI Ying et al.;(5),1221—1232AN Junling;see QU Yu et al.;(4),787-800AN Junling;see WANG Feng et al.;(6),1331-1342Ania POLOMSKA-HARLICK;see Jieshun ZHU et al.;(4),743-754Baek-Min KIM;see Seong-Joong KIM et al.;(4),863-878BAI Tao;see LI Gang et al.;(1),66-84BAO Qing;see YANG Jing et al.;(5),1147—1156BEI Naifang;  相似文献   

20.
正Journal of Meteorological Research is an international academic journal in atmospheric sciences edited and published by Acta Meteorologica Sinica Press,sponsored by the Chinese Meteorological Society.It has been acting as a bridge of academic exchange between Chinese and foreign meteorologists and aiming at introduction of the current advancements in atmospheric sciences in China.The journal columns include Articles.Note and Correspondence,and research letters.Contributions from all over the world are welcome.  相似文献   

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