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正CC BY OPEN ACCESS LICENCE This is a licence agreement under which you, the author, retain copyright in your article, and grant Informa UK Limited registered in England under no. 1072954 trading as TaylorFrancis Group, Registered Office:5 Howick Place, London SW1P 1WG (hereinafter  相似文献   

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《大气和海洋科学快报》2009,(3):I0002-I0002
The author warrants that his/her contribution is original, has not been published previously, and is not under consideration for publication in any other refereed journals. And he/she has full power to make this grant. All authors sign for and accept responsibility for releasing this material.  相似文献   

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1. IntroductionInvestigations about atmospheric LFW have been a focus of research since Madden andJulian/s outstanding analysis works (1971, 1972). Many dynamical and thermal mechanisms(Chao et al., 1996; Fu et al., 1998; Hendon et al., 1998; Krishnamurti et al., 1988; Lau andChan, 1988) have been advised to explain LFW. Among them are oceanic effects, such as SSTeffect, thermal forcing and others. Usually atmosphere and ocean are taken as a coupled system, which is used to explain ENS…  相似文献   

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“中国人工影响天气事业50周年纪念大会暨第十五届全国云降水与人工影响天气科学会议”于2008年10月8~11日在吉林省长春市召开,会议由中国气象学会秘书处、中国气象局预测减灾司主办,中国气象科学研究院、吉林省气象局承办。来自财政部、科技部、农业部、中国气象局,各省、市气象局,有关院校和科研院所等单位的近500名代表参加了会议。中国气象局局长郑国光与吉林省副省长王守臣出席纪念大会并致辞,中国气象局副局长矫梅燕主持会议。  相似文献   

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OrganizedbytheNationalOceanographicBureauwiththeparticipationoftheChinaMeteorologicalAdministration(CMA),theChineseAcademyofSciences(CAMS)andtheChineseMinistryofLandandResourcesetc.,theexpeditionteam(thefirstoneinChina),consistingof124members,setoutfromSh…  相似文献   

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Abstract

The importance of measurements of the vertical distribution of odd nitrogen in studies of ozone chemistry and climate change has long being recognized. In this paper, we use the optimal estimation method developed by Rodgers (1976, 1990) to retrieve NO2 vertical profiles from slant column observations made with a portable ultraviolet (UV)‐visible zenith‐sky spectrometer operated on the ground during the Middle Atmosphere Nitrogen TRend Assessment (MANTRA) balloon campaign carried out at Vanscoy, Saskatchewan, Canada (52°N, 107°W), from 18 to 25 August 1998. Late summer was chosen for the campaign because the stratospheric zonal wind velocity changes sign at that time. Under such conditions the stratospheric winds are at a minimum, leaving the stratosphere in a dynamically quiescent state and closer to photochemical control (Fahey et al., 2001; Fioletov and Shepherd, 2003). The NO2 profile retrieved from the ground‐based observations is compared with the co‐located and simultaneous NO2 profile measured by a balloon‐borne UV‐visible spectrometer during sunrise on 24 August. Good agreement is observed, giving us confidence in the retrieval technique adopted. The retrieved NO2 profiles are also compared with the output of the Model for Evaluating oZONe trends (MEZON) 3D stratospheric chemical transport model. It is observed that, for altitudes below the peak concentration, the model underestimates the NO2 amount, and at the altitude of peak concentration, the model values lie between the values measured from the balloon and those retrieved from the ground‐based measurements. Nevertheless, the model reproduces the general shape of the retrieved profiles, including the altitude of the NO2 maximum, for both sunrise and sunset conditions.  相似文献   

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The stalagmite δ18O record is known to be associated with the climate, but the specifics of the relationship remain unclear. It may not represent variation in air temperature or precipitation, but instead reflect integral changes of monsoon circulation, especially water vapor sources(the so-called "circulation effect"). Since large-scale atmospheric-oceanic modes such as the Atlantic Multidecadal Oscillation(AMO), Pacific Decadal Oscillation(PDO), and North Atlantic Oscillation(NAO) exert significant effects on Asian monsoon, in this paper the authors investigate the relationships of the East Asian stalagmite δ18O record with these modes. The last three centuries form the focus of our study, for which the authors use reconstructed as well as instrumental data. Considering the impacts of human activity, our analysis is conducted with respect to two periods—the pre- and post-industrial periods. The results show significant lead-lag connections: a positive correlation peaks when the PDO leads East Asian stalagmite δ18O by 3 years, which is persistent over the past 300 years; while the relationships of the AMO and NAO with the East Asian stalagmite δ18O record show significant differences in the post-industrial relative to the pre-industrial period. This implies that the East Asian stalagmite δ18O record may primarily reflect the PDO signal.  相似文献   

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大气海洋环境数值模拟中的若干计算问题   总被引:1,自引:0,他引:1  
为了适应发展气候数值模拟和环境数值模拟的需要,综合介绍了与此密切有关的若干计算问题。首先,指出这类问题易于出现计算紊乱、非物理解和非线性计算不稳定,同时,简要介绍造成这些问题出现的三种机理:虚假频散、能量关系破坏和能谱的非线性转移。然后,把这类问题归结为一种“发展方程”,给出了与此有关的几个定理,阐述了计算稳定性、能量守恒性和算子非负性之间的密切关系。接着,分别介绍了多种完全平方守恒的差分格式的构造方法,其中包括隐式的和显式的完全平方守恒的差分格式,高时间精度和高阶紧致的完全平方守恒的差分格式,同时也给出若干具体算例说明这些格式的计算效果。最后,对全文作了小结,并指出今后应进一步研究的若干重要问题。  相似文献   

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南极考察:我院逯昌贵参加了中国第十八次南极考察队度夏考察。我院还派出河北省滦平气象站李国辉、辽宁省沈阳观象台杨宝伟和黑龙江省龙凤山本底站代鑫参加了第十八次南极气象考察,分别在南极长城站和中山站越冬。本次考察在长城和中山两站更换了风观测塔及遥测自动站仪器,更新了  相似文献   

11.
顾薇  陈丽娟 《气象》2019,45(1):126-134
为更好地了解2018年夏季(6—8月)我国主要气候异常特征及成因,本文利用我国气象要素站点资料、再分析大气环流资料和全球海温数据分析了2018年夏季我国降水和气温的异常特征、东亚大气环流特征及海温对我国气候的影响。结果显示2018年夏季全国平均降水量较常年同期偏多9.6%,我国中东部地区降水呈现“南北多、中间少”的分布特征,北方和华南大部降水较常年同期偏多、长江中下游降水明显偏少。降水的上述异常特征受到东亚副热带和中高纬大气环流的共同影响。2018年夏季东亚副热带高空急流和西太平洋副热带高压位置都明显偏北,东亚沿岸由南至北为“负—正—负”的高度距平分布, 呈现出“东亚—太平洋型”遥相关负位相的特征,菲律宾附近对流层低层大气维持异常的气旋式环流,东亚副热带夏季风异常偏强。同时,欧亚中高纬度大气呈现“两槽一脊”的异常高度分布特征。在副热带和中高纬大气环流的这种配置下,我国北方地区以异常偏南风为主,有利于暖湿气流的输送,降水偏多;华南地区在偏强的热带对流活动影响下,降水也总体偏多;而长江中下游地区则以明显的辐散下沉运动为主,降水偏少。从外强迫因子来看,2017年10月至2018年4月发生的La Nina事件对东亚夏季风偏强及我国降水“南北多、中间少”的异常特征起到了重要作用。  相似文献   

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This paper reviews the progress in our understanding of the atmospheric response to midlatitude oceanic fronts and eddies,emphasizing the Kuroshio-Oyashio Extension(KOE)region.Oceanic perturbations of interest consist of sharp oceanic fronts,temperature anomalies associated with mesoscale eddies,and to some extent even higher-frequency submesoscale variability.The focus is on the free atmosphere above the boundary layer.As the midlatitude atmosphere is dominated by vigorous transient eddy activity in the storm track,the response of both the time-mean flow and the storm track is assessed.The storm track response arguably overwhelms the mean-flow response and makes the latter hard to detect from observations.Oceanic frontal impacts on the mesoscale structures of individual synoptic storms are discussed,followed by the role of oceanic fronts in maintaining the storm track as a whole.KOE fronts exhibit significant decadal variability and can therefore presumably modulate the storm track.Relevant studies are summarized and intercompared.Current understanding has advanced greatly but is still subject to large uncertainties arising from inadequate data resolution and other factors.Recent modeling studies highlighted the importance of mesoscale eddies and probably even submesoscale processes in maintaining the storm track but confirmation and validation are still needed.Moreover,the atmospheric response can potentially provide a feedback mechanism for the North Pacific climate.By reviewing the above aspects,we envision that future research shall focus more upon the interaction between smaller-scale oceanic processes(fronts,eddies,submesoscale features)and atmospheric processes(fronts,extratropical cyclones etc.),in an integrated way,within the context of different climate background states.  相似文献   

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科学基金在推动大气科学资料共享服务上取得初步成效   总被引:1,自引:0,他引:1  
科学资料是科学研究的根本基础和科学研究赖以继续发展的物质积累和保障。是无数科学家和整个国家科技成果体系中的重要产出和组成部分,是重要的国家资源。在全球信息化的今天,科学资料管理和共享体系建设能力直接关系到整个国家科技创新能力,成为国家科技管理水平和创新能力高低的试金石。1993年,国家自然科学基金委员会地球科学部率先在国内试点资助建立了“南京大气资料服务中心”,以推动科学基金大气科学领域资助项目中产生的重要科学资料的管理和“资料共享”。通过近10a的努力,该资料服务中心建设取得了一定成绩并积累了不少宝贵经验,为推动我国大气科学资源、资料的共享做出了有益的探索和贡献。  相似文献   

14.
利用全球海洋—大气快速耦合模式(Fast Ocean-Atmosphere Model,FOAM),采用模式中的初值方法,研究了湾流区海温再现过程及其对北半球大气环流和气候的影响。FOAM模式很好地模拟了北大西洋湾流区的海温"再现"过程,模式中海面热通量异常与SST异常表现出不同步的响应特征。海面热通量异常在初冬季节达到最大值,而SST异常滞后,在冬季晚期达到最大值,从而在初冬和晚冬对北半球大气环流造成不同的影响。初冬季节北半球大气环流主要受海洋热通量异常的强迫,在北大西洋和北太平洋上空呈现相当正压的异常低压槽响应,北极地区为异常高压脊,类似北极涛动的负位相,可能造成欧洲南部和北非大陆气温偏高,亚洲大陆气温偏低。而晚冬季节北半球大气环流主要受SST异常的驱动,在北大西洋和北太平洋上空表现为相当正压的异常高压脊响应,北极地区为异常低压槽,类似北极涛动的正位相,可能造成欧洲南部和北非大陆气温偏低,亚洲大陆气温偏高,中国东部降水异常偏多30%左右。北太平洋大气环流的异常由北大西洋湾流区海洋热通量和SST异常强迫下游大气环流所激发,进一步通过Rossby驻波的能量频散东传至北太平洋而造成的。  相似文献   

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马静  徐海明  董昌明 《大气科学》2014,38(3):438-452
采用动态合成、带通滤波等方法,通过对冬季黑潮延伸区暖、冷两个中尺度海洋涡旋的分析,研究了大气对中尺度海洋涡旋的响应特征。结果表明,海表温度(SST)与近海面风速的正相关关系在涡旋的动态合成图上清晰可见,暖(冷)涡上空对应10 m风速的极大(小)值,即海洋对大气的强迫作用在日时间尺度上表现显著;SST高低值中心基本对应10 m风无辐散区,暖(冷)涡上空为异常正(负)涡度分布;暖(冷)涡上空潜热、感热通量增大(减小),降低(增大)大气稳定度,从而加强(减弱)边界层垂直混合作用,使得海洋大气边界层增厚(变薄)。暖(冷)涡旋上空对应摩擦速度极大(小)值,反映了湍流粘性力在高(低)海温中心增大(减小)的特征,表明动量垂直混合机制在中小尺度海气相互作用中起着主要作用。中尺度海洋涡旋能够影响大气瞬变扰动,大气瞬变扰动强度在暖(冷)涡下游上空出现极大(小)值,该影响不仅表现在海洋大气边界层,在自由大气中低层也有较为清晰的反映。此外,从能量转换的角度入手,发现斜压能量转换在中尺度海洋涡旋影响大气瞬变扰动强度中贡献明显。  相似文献   

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This paper presents a unique set of observations of nearlycoincident and progressive oceanic and marine atmospheric boundary-layer (MABL) fronts in a coastal zone. The event was observed during the afternoon of 12 May 1996 at the United States Army Corps of Engineers, Coastal Engineering Research Center, Field Research Facility pier at Duck, North Carolina. The oceanic front was warm and fresh. Current variabilityaccompanied the oceanic front. A marked MABL front preceded the oceanic front by several minutes and had characteristics of a sea-breezefront. This MABL front separated warmer and dryer pre-frontal air from cooler and moister post-frontal air. Wind direction and wind speedvariability accompanied the MABL front. The sea-surface roughness signatures of both fronts were detected by an X-band pulsed Doppler radar. Supporting data are used to identify each front detected by the radar and to calculate each front's velocity. In an attempt to explain the sea-surface roughness variations associated with each front, the radar data are compared to corresponding variations in wind speed, wind direction, and air-sea temperature difference.  相似文献   

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国家自然科学基金(NSFC)在促进我国基础科学研究方面,一直以来扮演着重要的角色.为了量化评估资助效果,分析给出大气科学支持项目产出的SCIE论文及影响力.科睿唯安Web of Science科学文献数据库于2008年9月开始,标注论文得到的科学基金资助信息,因此从精确性方面考虑,分析出版年为2009—2021年大气科...  相似文献   

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通过采用一种较好地考虑了海气通量交换对下垫面特征非线性依赖的通量计算方案,利用较成熟的逐日通量距平耦合方案实现了次网格尺度海冰非均匀条件下一个全球大气环流模式和一个全球海洋环流模式在高纬地区的耦合,并完成了一个50年的长期积分。模拟结果表明,通量计算方案中水道的作用是合理的,耦合模式能较好地模拟出北半球高纬海冰的主要地理分布特征,但夏季北冰洋内部靠近欧亚大陆部分边缘海区海冰密集度偏大。  相似文献   

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