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1.
本文研究发现太平洋–日本遥相关型(PJ)和地中海–欧亚北部遥相关型(MnE)对东亚夏季气温存在显著的协同影响。当PJ和MnE处于同位相时,两者相关的大气环流在东亚中部地区相互叠加抵消,从而对该地区气温的影响较弱,而此时显著的气温异常主要位于东亚北部。相反,当PJ和MnE处于反位相时,两者相关的大气环流在东亚地区相互叠加增强,从而对东亚中部和亚洲北部地区的气温产生显著影响。因此,在东亚夏季气温变化的理解与预测中需要考虑这两个遥相关的协同作用。 相似文献
2.
夏季东亚高空急流与太平洋-日本遥相关型的关系 总被引：1，自引：1，他引：1
利用NCEP/NCAR和NOAA月平均资料,采用奇异值分解方法分析了夏季东亚高空纬向风场和西北太平洋海表温度(SST)的耦合关系,并据此研究了东亚副热带高空急流和太平洋-日本(Pacific-Japan,PJ)遥相关型的可能联系。合成分析结果表明,东亚副热带高空急流正模态年,急流偏南偏强,对流层上层南亚高压增强东进,中层西太平洋副热带高压加强西伸,菲律宾周边海域SST升高,中纬度黑潮延伸体区SST降低,菲律宾海和热带西太平洋地区对流活动偏弱,日本海和黑潮延伸体海区对流活动增强,对应PJ遥相关型的负位相;而东亚副热带高空急流负模态年,急流偏北偏弱,对流层上层南亚高压减弱西退,中层西太平洋副热带高压减弱东撤,菲律宾周边SST降低,中纬度黑潮延伸体区SST升高,菲律宾海和热带西太平洋地区对流活动强盛,日本海和黑潮延伸体海区对流活动减弱,对应PJ遥相关型的正位相。由于夏季东亚副热带高空急流活动与PJ遥相关型存在关联,PJ遥相关型可能是东亚副热带高空急流响应太平洋海温异常的纽带。 相似文献
3.
本文用10年(1980—1989)夏季北半球500hPa候平均高度场资料进行遥相关分析,得到东亚太平洋型(EAP)和西欧型(WE)两种遥相关型及西亚-太平洋-大西洋振荡,并对高度场进行主成分分析(PCA),讨论了环流的时空分布特征. 相似文献
4.
亚洲—太平洋季风区的遥相关研究 总被引：15，自引：6，他引：9
亚洲-太平洋季风区各季风子系统间的相互作用对季风区甚至全球的气候变化都有非常显著的影响.文中根据国内外相关研究,重点分析和评述了在亚洲-太平洋季风区中4种季节内时间尺度的遥相关关系,清楚地揭示了印度夏季风、东亚夏季风和西北太平洋夏季风之间的相互作用.研究发现:(1) 在亚洲季风爆发初期,印度夏季风的爆发相对于中国长江流域梅雨的开始存在相差大约两周的超前关系,形成从印度西南部经孟加拉湾到达中国长江流域及日本南部的遥相关型,即"南支"遥相关型.(2) 在季风盛行期间,长江流域降水明显受热带西北太平洋夏季风的影响,与西北太平洋夏季风降水呈反相关关系,即当季风减弱时,长江流域夏季降水偏多.(3) 与长江流域降水相反,华北雨季(7月第4候-8月第3候)则与西北太平洋夏季风降水呈正相关关系,当西北太平洋夏季风强时,西太平洋副热带高压异常偏北偏东,副高西南侧的异常东南水汽输送在中国华北地区上空辐合,给该地区降水偏多提供了充足的水汽条件.(4) 华北夏季降水同时还与印度夏季风呈正相关关系,在夏季风盛行期间,形成由印度西北部经青藏高原到中国华北地区的西南-东北走向的遥相关型,即"北支"遥相关型. 上述4种遥相关关系,反映了亚洲夏季风季节北推过程中,印度夏季风、东亚夏季风和西北太平洋夏季风子系统之间的关联. 相似文献
5.
北半球夏季位势高度场遥相关型的观测研究 总被引：3，自引：0，他引：3
本文利用点相关普查和经验正交函数展开分析了北半球夏季500hPa位势高度场的年际变化特征,指出在北半球夏季主要存在4种遥相关型,它们分别被称作亚洲/北美型、欧亚型、东北太平洋型和北美/西欧型.其中前两种遥相关型和东亚夏季大气环流年际异常有直接的联系.北半球夏季遥相关型的揭示对于研究东亚大气环流年际变异的机理及其预报有参考价值. 相似文献
6.
台风在我国登陆地点的年际变化及其与夏季东亚/太平洋型遥相关的关系 总被引：9，自引：3，他引：6
本文利用1979～2007年日本气象厅JRA-25风场和高度场再分析资料和美国JTWC热带气旋的观测资料分析了7～9月份西北太平洋台风和热带气旋 (TC) 在我国登陆地点的年际变化及其与北半球夏季大气环流异常的东亚/太平洋型 (即EAP型) 遥相关的关系, 特别是分析了7～9月份在厦门以北登陆台风和TC数量的年际变化与夏季 (6～8月) EAP指数的相关。分析结果表明: 当夏季 (6～8月) EAP指数为高指数时, 则7～9月份在东亚和西北太平洋上空500 hPa高度场异常将出现 “－, +, －” EAP型遥相关的波列分布, 这时西太平洋副热带高压的位置偏北、 偏东。在这种情况下, 西北太平洋上较多的台风和TC的移动路径偏北, 这引起了7～9月份在我国厦门以北沿海登陆的台风和TC数量偏多。反之, 当夏季 (6～8月) EAP指数为低指数时, 在东亚和西北太平洋上空500 hPa高度场异常为 “+, －, +” 的 EAP型遥相关的波列分布, 这时西太平洋副热带高压的位置偏南、 偏西。在这种情况下, 西北太平洋上较多的台风和TC移动路径偏南, 这引起了7～9月份在我国厦门以北沿海登陆的台风和TC数量偏少, 较多的台风和TC在厦门以南的华南沿海登陆。 相似文献
7.
利用夏季东亚地区500 h Pa高度场和菲律宾附近的降水场进行SVD分析,将东亚500 h Pa高度场对应的时间序列定义为PJ指数,该指数不仅清楚地反映PJ型的年际变化,而且反应出PJ型的年代际变化,即500 h Pa高度场型态在20世纪70年代末由"气旋、反气旋、气旋"型突变为"反气旋、气旋、反气旋"型。本文研究表明PJ指数的年际变化与ENSO事件有密切的联系:El Ni1o事件通过电容器充电效应使印度洋海温增暖,而增暖的印度洋海温在菲律宾海附近强迫出异常反气旋,并沿东亚沿岸激发出PJ遥相关型。而PJ型态的年代际变化与热带印度洋SST的持续增暖有关。虽然许多学者认为是菲律宾附近海温异常引起对流异常,并沿东亚沿岸激发出PJ遥相关型,但我们认为该区域的海温变化并不是造成PJ型年际和年代际变化的原因,而是由于该区域有反气旋(或者气旋)异常,从而辐射增加(减少),蒸发减弱(增加),温跃层下降(上升),SST变暖(变冷),该区域的海温变暖意味着对流是减弱的。本文进一步利用大气环流模式ECHAM5.4进行数值试验,结果表明:当热带印度洋增暖时,在菲律宾海附近强迫出反气旋,并沿东亚激发出"反气旋、气旋、反气旋"PJ遥相关型。 相似文献
8.
1993年北半球环流特征及其对我国天气气候的影响 总被引：4，自引：0，他引：4
１９９３年北半球主要环流特征表现为：５００ｈＰａ副产持续加强西伸，位置偏南；亚洲中纬度春，夏经向环流发展，东亚太平洋遥相关型稳定；西藏高原５００ｈＰａ位势高度持续偏高，印缅槽持续偏弱；１００ｈＰａ位势高度场低纬持续偏高，中，高纬持续偏低，夏季南亚高压位置异常偏高。热带海洋出现明显异常，一次新的厄尔尼诺现象发生。热带海洋和北半球大气环流的异常对我国天气气候产生明显影响。 相似文献
9.
利用季节循环的全球观测海表温度及海冰驱动NCARCam3全球大气环流模式的100a模拟结果,通过定义东亚夏季风指数,分析了模拟的大气内部变化中东亚夏季风的变化特征。结果表明：模拟的东亚夏季风自然变率主要表现为3—7a较显著的年际周期,并具有较明显的年代际变化特征。在弱夏季风年代,亚洲大陆海平面气压增强,日本附近及东亚沿海地区海平面气压降低;500hPa位势高度上,欧洲地区为负高度距平,里海附近地区为正高度距平,日本及其以东太平洋为负高度距平,易形成类似欧亚（EU）型的遥相关波列。在强夏季风年代,其环流异常分布基本与弱夏季风年代相反。模拟的东亚夏季风变化与夏季大气内部500hPa高度场上EU型遥相关波列的关系密切。 相似文献
10.
基于1957~2017年观测和再分析资料,合成分析了北太平洋年代际振荡(Pacific decadal oscillation,PDO)不同位相下El Ni?o发展年和La Nina年东亚夏季风的环流、降水特征及季节内变化。结果表明,PDO正、负位相作为背景场,分别对El Ni?o发展年、La Nina年东亚夏季风及夏季降水具有加强作用。PDO正位相一方面可增强El Ni?o发展年夏季热带中东太平洋暖海温异常信号,另一方面通过冷海温状态加强中高纬东亚大陆与西北太平洋的环流异常,从而在一定程度上增强了东亚夏季风环流的异常程度;反之,PDO负位相则增强了La Nina年热带海气相互作用以及中高纬环流(如东北亚反气旋)的异常。在季节内变化方面,El Ni?o发展年6月贝湖以东反气旋性环流为东亚地区带来稳定的北风异常,东北亚位势高度减弱;7月开始,环流形势发生调整,日本以东洋面出现气旋性异常,东亚大陆偏北风及位势高度负异常均得到加强;8月,随着东亚夏季风季节进程和El Ni?o发展,西太平洋出现气旋性环流异常,东亚副热带位势高度进一步降低,西北太平洋副热带高压(简称副高)明显东退。La Nina年6月异常较弱,主要环流差异自7月西北太平洋为大范围气旋性异常控制开始,东亚-太平洋遥相关型显著,副高于季节内始终偏弱偏东。上述两种情况下,均造成东亚地区夏季降水总体上偏少,尤其是中国北方降水显著偏少。 相似文献
11.
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.
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
13.
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
15.
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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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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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
18.
《大气和海洋科学快报》2013,(1):67
正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.SUBMISSIONAll submitted 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