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北京春季一次持续浮尘和污染天气过程分析 总被引：3，自引：2，他引：3
2001年4月底5月初北京地区出现了一次以浮尘天气为主，夹杂轻雾、雷阵雨、烟幕等复杂天气过程的持续重污染事件，给北京地区的生产和生活带来了较大的影响。文章主要从天气形势上分析了北京浮尘天气形成的原因和持续空气污染的气象条件。结果表明，此次过程是由于高空冷涡发展东移，蒙古气旋发展和地面冷锋移动经过蒙古国南部和华北北部等干燥、疏松的地表形成扬沙、沙尘暴，大量的细小沙尘粒子随高空偏西气流携带而至北京，形成浮尘天气。本地低空处于弱辐合区，层结稳定，风速小、逆温频繁，这些均不利于沙尘粒子和本地污染物的扩散，导致连续可吸入颗粒物重污染的形成。 相似文献
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“4．5”西北区浮尘沙尘暴天气初析 总被引：1，自引：0，他引：1
初步分析了１９９４年４月５日－１１日西北区浮尘和沙尘暴天气，指出这次天气具有持续时间长、范围广、强风时间短、沙尘密、沉降量大和地域性显著的特征。它是在天气环流热力和动力作用下形成的，主要成因是热浪进入青藏高原加强，西北区上空大气异常增温，地面气旋性热环流发展是浮尘天气的启动因子，蒙古冷高压底部强气压梯度力的作用激化了浮尘和沙尘暴天气，沙尘暴消散后大气层结稳定使浮尘得以维持呈准静止状态，在强冷空气影响下浮尘天气结束。 相似文献
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2013年3月8~9日甘肃省出现了一次区域性的大风沙尘暴天气过程,此后到14日甘肃中东部一直维持浮尘天气,这样范围广、持续时间长的沙尘天气为近年来罕见。本文分析了此次沙尘天气过程的天气气候特征以及特殊气象条件对连续浮尘天气的影响,并以兰州市为例基于HYSPLIT-4轨迹模式探讨了浮尘天气过程的沙尘颗粒传输特征。结果表明:(1)前期暖干的气候背景有利于此次大范围沙尘天气的发生;(2)8~9日冷锋后的偏北大风引发甘肃省出现区域性大风沙尘暴天气,11日河西再次出现扬沙、沙尘暴天气,沙尘粒子沿西北气流向下游地区输送,致使12日河东出现浮尘天气的站数明显增多;(3)9日大风沙尘暴天气过后,甘肃省中东部边界层处在弱的偏东风环境中,大气层结长时间较稳定,沙尘污染物不易扩散;(4)在连续浮尘天气期间,甘肃省各地上空频繁出现逆温层,且逆温层高度在9日沙尘暴天气过后有明显抬升,阻挡了低层空气的上升运动,以致沙尘粒子聚集在700 h Pa以下。同时还发现,边界层上部逆温层的逆温温差越大,厚度越厚,造成浮尘天气的强度越强;(5)兰州市9~10日出现的浮尘天气起源于8日河西走廊及蒙古地区的沙尘暴,11日河西走廊再次爆发的沙尘暴天气对河东的浮尘天气影响较大。此外,10~13日陕西南部也出现了浮尘天气,"东高西低"的地面形势使此地上空漂浮的沙尘粒子处在偏东风的环境中,对甘肃中东部地区的浮尘天气有一定的回流输送作用。 相似文献
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2006年春季一次引起华北地区强沉降的沙尘暴过程的模拟研究 总被引：3，自引：2，他引：1
2006年春季是我国北方地区2000年以来强沙尘暴过程最多的一年,浮尘和扬沙天气更是频繁发生.尽管,4月16～17日过程不是2006年春季最强的沙尘暴过程,但其在华北地区引起了严重的沉降,尤其对京津地区影响较大.这是一次由蒙古气旋引发的强沙尘暴过程.利用沙尘天气预测系统(IAPS 2.0)对该次强沙尘暴过程进行了模拟试验,结果表明:该系统对沙尘天气的起沙和输送过程有较好的模拟能力,基本模拟出了这次强沙尘暴的发生和移动;沙尘受对流层中低层偏西风的作用输送到华北地区,并从山东半岛越过渤海湾向东输送;主要的沙尘源地是蒙古国南部和我国西北的内蒙古、新疆西部、甘肃、陕西北部,而起尘最大的地区在蒙古国和内蒙古的沙漠、戈壁地区;沉降最严重的地区是沙尘源区及其附近,可达到50 g*m-2,其他地区的总沉降量在10 g*m-2左右. 相似文献
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基于1999—2019年地面气象观测资料,对东亚主要沙尘源地(蒙古国、中国新疆和内蒙古)及中国沙源地下游地区的沙尘天气频数演变特征进行了分析,结果表明：蒙古国是沙尘天气发生最严重的地区,且有明显增加的趋势,扬沙、沙尘暴和强沙尘暴均远高于其他区域。中国整体沙尘天气数量显著减少,新疆快速增多,内蒙古和下游地区明显减少。新疆浮尘发生频次最高,近21 a线性倾向呈明显上升趋势;内蒙古扬沙频次最高,强沙尘暴最少,4类天气均呈逐年减少趋势;我国下游地区多发浮尘和扬沙,沙尘暴和强沙尘暴发生次数很少,全部沙尘天气呈减少趋势。1999—2004年为我国沙尘天气高发期,2005—2019年明显减少,其中2010—2014年减少速度最快。沙尘源地对我国沙尘天气总数的贡献持续增大,从2000年初的39%增长到2015年之后的71%。作为沙尘源地,蒙古国对沙尘天气产生的作用有所增强,而内蒙古则在减弱;国内沙尘源地导致的能够影响并扩展至中国下游地区和下游国家的强沙尘天气显著减少。 相似文献
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前 言和我国北方大部分地区一样 ,今年春季 ,陕西沙尘天气 (沙尘暴、扬沙和浮尘 )频繁 ,陕北长城沿线榆林、横山、靖边、定边仅 4月份就出现沙尘暴 3～ 5次 ,扬沙 6 1 5次 ,浮尘 2 3次 ,其中 ,定边春季 ( 3～ 5月 )共出现沙尘暴1 2次 ,扬沙、浮尘 32次。 4月 9日、1 3日、1 9日和 2 9日古城西安出现的 4次扬沙天气 ,更是引起了各级政府和广大群众的高度重视。为此 ,我们对陕西沙尘暴的时空分布、形成原因及防御对策进行了分析 ;对历史上沙尘暴天气对应的大气环流特征进行分析归纳 ,划分为不同的大气环流类型 ,建立沙尘暴归类判别分析预报模… 相似文献
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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 Nio3.4 index in summer and autumn but negatively correlated in spring and winter. 相似文献
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Fei LIU Chen XING Jinbao LI Bin WANG Jing CHAI Chaochao GAO Gang HUANG Jian LIU Deliang CHEN 《大气科学进展》2020,37(7):663-670
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
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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
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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(Stl), 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
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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
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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
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Analysis of Atmospheric Boundary Layer Height Characteristics over the Arctic Ocean Using the Aircraft and GPS Soundings 
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下载免费PDF全文 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
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《大气科学进展》2014,(6)
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
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《Acta Meteorologica Sinica》2014,(6)
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