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经圈环流对定常波传播的影响 总被引：1，自引：0，他引：1
在一般斜压大气中，基本气流中包含经圈环流时，定常波传播不仅能穿过东风带，而且明显增强。在基流含有经圈环流的情况下，北半球中纬度地形强迫可引起低纬大气的显著响应，这表明经圈环流在中低纬定常响应的相互联系中起着重要作用；北半球中纬度热力强迫可产生类似北半球夏季季风环流的波列分布，这说明经圈环流在夏季季风环流的形成中起着一定的作用；在赤道东太平洋加热强迫情况下，在冬半球可引起ＰＮＡ型的定常波传播波列，而在夏半球却没有明显的ＰＮＡ特征。这表明经圈环流对冬、夏半球的定常波传播路径有着显著的影响。 相似文献
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夏季长江流域暴雨洪涝灾害的天气气候条件 总被引：36，自引：22，他引：36
利用NCEP/NCAR再分析资料,探讨夏季中国东部长江流域严重洪涝灾害发生时的天气气候异常特征.分析表明:东亚夏季风环流偏弱是夏季长江流域发生严重暴雨洪涝灾害的气候特征.天气特征是东亚地区东、西、南、北天气尺度系统的最佳配合以及东亚大气环流出现较显著的20～30天的低频振荡.东亚中高纬大气环流出现20～30天的低频振荡,有利于青藏高原上空的低压系统沿着中纬度东传到115～125°E附近,造成长江流域梅雨锋低压扰动加强;东亚低纬大气环流出现20～30天的低频振荡,有利于印度洋、南海和热带西太平洋的水汽输送到长江流域,为长江流域暴雨提供持续充足的水汽来源.夏季西太平洋副热带高压西伸出现20～30天的低频振荡,有利于低压系统在长江流域(115～125°E)再生和维持. 相似文献
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关于大气环流型季节特征形成的物理因子的数值试验 总被引：1，自引：0，他引：1
本文着重研究大气环流季节特征的成因问题。模式试验中将牛顿强迫项的平衡温度斜压结构作类似冬夏气候特征的变化,且加入南北半球大地形强迫作用,研究大气环流型对冬夏全球热力结构特征以及南北半球大地形强迫效应的响应。 相似文献
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澳洲夏季风热源低频变化对北半球冬季风影响的数值研究 总被引：1，自引：1，他引：1
采用ｐ－σ混合坐标系的５层原始方程模式研究了与澳洲夏季风低频变化相伴随的对流性低频加热源所激发的大气强迫波和东亚冬季风的关系，结果表明澳洲夏季风低频热源可引起北半球副热带高低层环流、东西向Ｗａｌｋｅｒ环流。经向环流、越赤道气流的低频振荡，其振荡周期、强度与热源的振荡周期、强度有关。结果还进一步表明，澳洲低频热源可激发出扰动的北传，从而引起北半球副热带环流、副热带西风急流的低频振荡，澳洲夏季风活跃后 相似文献
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本文采用OSU-AGCM动力框架加入牛顿加热项构成的简化大气环流模式,研究澳洲大陆热力强迫与南北半球环流异常的相关关系。本文对不同平衡温度模拟结果的差异(偏差场)进行了分析,探讨某局地热力强迫对全球其它区域环流异常的影响效应.数值试验结果表明,南北半球海陆热力结构有利于两半球行星尺度经向环流的加强及其低纬跨赤道气流的形成:南半球澳洲大陆热力强迫可以通过东、西风带侧向藕合效应,显著地影响北半球中纬西风带急流状况;二维Rossby波能量频散径向传播可能足澳洲热力强迫与北半球常定环流系统的异常变化相关现象的重要成因,且澳洲大陆强迫产生的径向波列路经与PNA、EU型相似. 相似文献
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华北夏季旱涝的前期环流异常及其与北太平洋海温的关系 总被引：10，自引：1，他引：10
文章分析了华北地区夏季旱涝的前期春季大气环流和北太平洋海温异常（ＳＳＴＡ）分布特征，探讨ＳＳＴＡ与异常环流的关系，并用ＯＳＵ－ＡＧＣＭ进行黑潮地区热源异常强迫的数值试验．结果表明，当春季北极低涡明显减弱，欧亚大陆中高纬度地区纬向环流加强，西太平洋副高位置偏北偏西，且存在负ＰＮＡ型异常环流时，华北地区夏季多雨涝；反之则少雨干旱．此时，西北太平洋和赤道东太平洋ＳＳＴ分别存在较大的正、负异常，它们与春季环流异常密切相关，黑潮区ＳＳＴＡ对北半球副热带及其以北的大气环流产生显著影响，正的ＳＳＴＡ是造成华北夏涝年的前期春季异常环流形势的重要因素． 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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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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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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《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
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DING Yihui WU Guoxiong Da-Lin ZHANG ZHANG Renhe Co-Chief Editors 《Acta Meteorologica Sinica》2014,28(5):669-670
As we will soon celebrate the 90th anniversary of the founding of the Chinese Meteorological Society （CMS）,Acta Meteorologica Sinica （AMS）,which was originally named as Bulletin of the Chinese Meteorological Society,has gone through 89 years of development and excitement since her first issue in July 1925.According to archived documents （CMS Editorial Committee,1925）,AMS was founded to report the research findings of Chinese meteorologists,record their recommendations for improving meteorological services,and share their common meteorological interests in order to promote the growth of AMS such that more members could be inspired to conduct atmospheric research and meteorological knowledge would be better disseminated to and benefit the general public.By upholding and carrying forward this purpose,AMS has published many highly valuable scientific papers.Some could be treated as classical articles,which have produced important influences on both domestic and international meteorological communities and the related fields. 相似文献