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1.
通过对1953—2012年金华地区60年66次大雪天气过程的气候特征、环流形势、中低层天气尺度系统等进行统计分析,得出:金华市大雪发生的频次在时间尺度上主要为准7年的周期振荡;大雪天气产生期间阻塞高压、中低纬锋区异常强盛,当南支槽与中高纬度转竖的横槽耦合叠加时,有利于形成大范围降雪天气;700hPa温度0℃线基本上都要南压到28°N或以南地区,850hPa温度0℃要南压到29°N以南;地面温度≤2℃,1000hPa温度0℃,925~850hPa温度≤-3℃,700hPa温度0℃,对流层中低层存在逆温;通过分析得出大雪短期预报的着眼点后,建立了金华市大雪预报概念模型与预报思路。  相似文献   

2.
江西大雪天气的时空变化及其影响系统分析   总被引:3,自引:0,他引:3  
郑婧  许爱华  刘波  许彬 《气象》2010,36(4):30-36
利用NCEP2.5°×2.5°再分析资料和常规观测资料,对1980—2008年江西省50次区域性大雪过程的时空变化及其影响系统进行归纳分析,得出:江西省大雪发生频次具有5年左右振荡周期,20世纪90年代以前发生大雪次数较多,变化幅度大,20世纪90年代以后年际变化减小。空间分布上,自西北向东南出现大雪的频次逐渐减少。大雪期间,阻塞高压、中低纬锋区异常强盛;80%的大雪天气存在阻塞高压,以贝加尔湖阻塞高压最多;70%受南支槽影响;700 hPa切变线是对流层中低层的主要影响系统,其南侧西南急流最大风速达16 m·s~(-1)以上,雪区位于冷式切变线以南1~3个纬距内,或暧式切变附近;当850 hPa和700 hPa同时存在切变线时,降雪天气更加明显;对流层中低层有98%的大雪天气存在逆温:1000 hPa温度1 C,925~850 hPa温度≤-2℃,700 hPa温度≤0℃;地面冷空气多为中路,蒙古冷高压异常强大。  相似文献   

3.
针对湖北省冬季大雪天气预报难题,使用常规观测资料和数值预报产品,分析了1988-2005年发生在湖北省冬季的15次大雪过程.结果表明.地面冷空气、700 hPa江南西南急流和500 hPa西风带低槽是决定湖北省冬季大雪的三个主要天气系统,700 hPa江南西南急流强弱决定湖北省大雪强度,地面冷空气强度决定湖北省降温幅度;归纳出有利湖北省大雪的温度条件的垂直分布特征;由于锋面抬升和两南低空急流的作用,在对称不稳定条件下产生倾斜上升和下沉运动,形成中尺度倾斜环流,在充沛环境水汽条件下,产生大雪天气;采取物理参数指标结合数值预报建立的湖北省大雪客观预报方法,在实时预报业务中预运行效果较好.  相似文献   

4.
1前言 冬季大雪是吉林地区的灾害性天气之一,它对丁农业生产、畜牧业、交通运输和人民生活有着重要的影响。因此,做好冬季大雪天气的预报是极其重要的。本文通过对1980—2005年吉林地区冬季大雪天气大气环流形势演变的分析,研究总结经验,为冬季预报大雪天气提供一些依据,对防灾减灾服务起到一定作用。  相似文献   

5.
对临安1959年12月-2011年3月的大雪资料统计分析,得出临安大雪气候特征;对1995--2011年的12次大雪过程的天气形势分析,得出产生大雪的主要天气系统有地面冷空气、500hPa高纬环流形势和中低纬南支槽、中低层逆温层、700hPa强盛暖湿气流或西南急流;冷空气活动路径主要有偏北路、西北路和偏北路加西北路,本文根据统计资料得出临安大雪预报步骤和方法。  相似文献   

6.
大雪是我市冬季的主要灾害天气之一,对工农业生产、邮电通讯、交通运输等影响极大,与我们的菜篮子也有直接关系。因此,做好大雪预报是公益服务和有偿专业服务的追切需要。本文在对天气背景及气象要素分析的基础上制作了包括数值预告产品应用在内的大雪  相似文献   

7.
近10年武汉市大雾变化特征及2006年一次大雾个例分析   总被引:1,自引:0,他引:1  
为了了解近一个时期武汉市大雾的时空变化特征、大气环流背景及有关物理要素场的分布情况,根据1995~2005年武汉市大雾观测记录,统计分析了这一时期武汉市大雾的变化特点,并对2006年3月10日出现在武汉市的一次大雾天气过程进行了分析。结果表明:近11年来,武汉市大雾日数继续下降,冬季大雾出现频率最高,春、秋季大雾频率次之,大雾持续时间明显延长;高空弱的偏西气流,中低层弱的暖湿气流,近地面有逆温层,地面为均压场等条件,是大雾形成的有利环流形势。  相似文献   

8.
刘桂琴  孟庆楠 《气象》1984,10(12):16-18
大雪常造成恶劣能见度和积雪,是冬季预报服务不容忽视的灾害性天气。大连冬季降水的气候分布,具有年际变化大且主要集中在几次重大天气过程的特点。以1月份为例,1951—1980年中出现的12次大雪或特大降雪的降水量之和(170毫米),占30年该月总降水量的65%以上。因此,认清大雪的天气形势,不仅有助于短期天气预报分析和服务,而且对中长期预报和气候分析工作也有一定作用。  相似文献   

9.
江西省冬季大雪气候概况和环流特征分析   总被引:2,自引:1,他引:1  
利用NCEP2.5°×2.5°再分析资料和常规观测资料,对1980--2008年江西省50次区域性大雪过程的气候概况、环流演变、热力层结、影响系统特征进行归纳分析。结果表明,江西省冬季大雪具有明显的年际、月际变化特征,冷冬年为大雪天气的多发年,进入暖冬期后,则有减少的趋势;空间变化上,出现大雪的频次基本上呈现出自西北向东南逐渐减少的特征,各地区积雪分布极不均匀。大雪期间,极涡、阻塞高压异常强而稳定,中低纬锋区异常强盛;超长波的稳定形势有利于天气背景的维持,造成连续性大雪。有80%的比例存在阻塞高压,以贝加尔湖阻塞高压最多;有70%的比例是受南支槽影响,当南支槽与中高纬度转竖的横槽同位叠加时,有利于引导极地强冷空气向副热带地区爆发,形成江西大范围降雪天气。对流层中低层多存在切变线,雪区位于冷式切变线以南1—3个纬距内或暖式切变附近,雪区伴随着暖切的南移而扩展;700hPa西南气流强盛,急流轴最大风速超过16m/s;当850hPa同时存在切变线时,降雪天气更剧烈。有98%的比例对流层中低层存在逆温,逆温高度平均在700-925hPa;温度垂直分布一般具有1000hPa温度≤0℃,925—850hPa温度≤-2℃,700hPa温度≤-2℃的特点。地面冷空气多为中路,蒙古冷高压异常强大,为降雪的产生创造良好的热力条件。  相似文献   

10.
利用天气学原理对2008年1月11日至29日发生在宁夏的持续阴雪、低温天气过程分析,发现在整个过程中由于极涡偏向亚洲地区,长波槽稳定地处于巴尔科什湖和贝加尔湖地区。中高层的高空为准纬向气流,中低层"东高西低"降雪天气形势有利,随着地面冷高压和热倒槽在宁夏的交替,全区出现14至18天的间歇性降雪。分析发现,在冬季"浅薄"的天气系统下,降雪过程的天气形势场、物理量等,在中低层的反应远比500h Pa清楚。中低层偏南气流和地面热倒槽前的回流,不仅为降雪天气的形成提供了充足水汽条件,还是不稳定抬升能量的主要来源。宁夏1月11日至29日间歇性的14至18天的降雪天气,刷新了历史同期的气象纪录。由于近地面强大的蒙古冷高压长时间控制宁夏,加之长时间的积雪和辐射降温,1月31日到2月1日宁夏出现了2007/2008年冬季以来的最低气温,部分测站最低气温创历史同期新低。  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.
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   

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.
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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