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Distributional features of δ^(18) O in precipitation in china

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Journal of Geographical sciences 1998年第2期8卷 57-64页

作者： ZHANG Xinpingdepartment of Geography, Hunan Normal university, Changsha 410081{2.Yao Tandonglanzhou Institute of Glaciology and Geocryology, CAS, lanzhou 730000{2.

According to calculation on available data, higher δ18O exists in atmospheric precipitation of southeastern and northwestern part of china, and the lower in Northeast china and the southern QinghaiTibet Plateau. In china temperature effect appears mainly in the inner continent of midhigh latitudes and the amount effect appears in southeastern coastal regions, the YunnanGuizhou Plateau and QinghaiTibet Plateau where the influence of monsoon climate is obvious. The meteoric water lines (MWLs) of different regions are of certain divergence, which is closely related to the stable isotopic fractionations of the two processes, namely the evaporation of origins and the precipitating of vapor.

关键词： δ18 O distribution temperature effect amount effect MWL.

Advanced information feedback strategy in intelligent two-route traffic flow systems

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Science china(Information sciences) 2010年第11期53卷 2265-2271页

作者： DONG ChuanFei1,2. MA Xu1,3 & WANG BingHong1,4 1department of Modern Physics and Nonlinear Science Center, university of Science and Technology of{2. (USTC), Hefei 2.002.,{2. 2.chool of Earth and atmospheric sciences, Georgia Institute of Technology, Atlanta, GA 30332. USA 3 department of Physics, Syracuse university, Syracuse, NY 132.4, USA 4The Research Center for Complex System Science, university of Shanghai for Science and Technology and Shanghai Academy of System Science, Shanghai 2.0093,{2. 1. department of Modern Physics and Nonlinear Science Center University of Science and Technology of China (USTC) Hefei 230026 China2. School of Earth and Atmospheric Sciences Georgia Institute of Technology Atlanta GA 30332 USA3. Department of Physics Syracuse University Syracuse NY 13244 USA4. The Research Center for Complex System Science University of Shanghai for Science and Technology and Shanghai Academy of System Science Shanghai 200093 China

The optimal information feedback has a significant effect on many socioeconomic systems like stock market and traffic systems aiming to make full use of resources. In this paper, we study dynamics of traffic flow with real-time information. The influence of a feedback strategy named vehicle number feedback strategy (VNFS) is introduced, in which we only calculate the vehicle number of first 500 route sites from the entrance. Moreover, the two-route traffic system has only one entrance and one exit, which is different from those in the previous work. Our model incorporates the effects of adaptability into the cellular automaton models of traffic flow, and simulation results by adopting this optimal information feedback strategy have demonstrated higher efficiency in controlling spatial distribution of traffic patterns than the other three information feedback strategies, i.e., TTFS, MVFS and CCFS.

关键词： vehicle number feedback strategy two-route selecting traffic flow intelligent vehicle cellular automaton model

Statistical characteristics of the double ridges of subtropical high in the Northern Hemisphere

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Science Bulletin 2005年第20期 82-87页

作者： ZHAN Ruifen1,2.3, LI Jianping1 & HE Jinhai2. 1. State Key Laboratory of Numerical Modeling for atmospheric Sci- ences and Geophysical Fluid Dynamics (LASG), Institute of Atmos- pheric Physics, Chinese Academy of sciences, Beijing 10002., {2. 2. department of atmospheric sciences, Institute of Meteorology, Nan- jing university of Information Science and Technology, Nanjing 2.0044,{2. 3. Graduate School of the Chinese Academy of sciences, Beijing 100039,{2.

The generality and some climatological charac- teristics of the double ridge systems of subtropical high (SH) are investigated statistically by using the daily NCEP/NCAR reanalysis data from 1958 to 1998. The results show that the SH double-ridge event is a common phenomenon in the Northern Hemisphere, with the distinct seasonal and re- gional features, that is, the majority of SH double-ridge geneses concentrate over the eastern North India Ocean- western North Pacific as well as the central North Pacific in the period from mid-July to mid-September. Especially over the western North Pacific subtropics, the SH double-ridge events are extremely active. It is found that the life cycle of most double-ridge events of western Pacific subtropical high (WPSH) is shorter but some still last longer. The WPSH dou- ble-ridge events occur most frequently from July to Septem- ber, while there is a paucity of occurrences during Novem- ber-March. Also, it is shown that the WPSH double-ridge events have a strong interannual variation with a certain periodicity which possesses a remarkably abrupt change in the mid-1970s. Additionally, the relationship between the WPSH double ridges and the meridional movement of WPSH is discussed.

关键词： subtropical high double ridges statistical characteristics meridional movement.

Asymptotic behavior of the shock solution for a class of nonlinear equations

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Progress in Natural Science:Materials International 2003年第10期 48-50页

作者： MO Jiaqi 1*, ZHU Jiang 2.and WANG Hui 3(1. department of Mathemtics, Anhui Normal university, Wuhu 2.1000,{2. 2. ICEES, Institute of atmospheric Physics, Chinese Academy of sciences, Beijing 10002.,{2. 3. National Natural Science Foundation of{2., Beijing 100085,{2.) department of Mathemtics Anhui Normal University Wuhu 241000 China ICEES Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China National Natural Science Foundation of china Beijing 100085 China

The high precision approximation of the shock solution for a class of nonlinear problems is obtained using a simple method.

关键词： nonlinear equation shock boundary layer.

Delta asymmetry:Concepts,characteristics,and depositional models

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Petroleum Science 2011年第3期8卷 278-289页

作者： Li Weiguo Janok P. Bhattacharya Wang Yingmin BP America Inc. Houston Texas77079 USA department of Earth and atmospheric {2. University of Houston Houston Texas 77204-5007 USA College of geosciences China University of Petroleum Beijing 102249 China

Delta asymmetry forms in wave-influenced settings where there is strong net longshore drift. Asymmetric deltas typically have two sediment sources and are characterized by morphology and facies asymmetry between the downdrift and the updrift sides. The downdrift, sourced primarily by the feeding river, are commonly influenced by mixed river and wave processes. Deposits on this side are muddy and consist of barrier, bar, lagoon, bay-fill, and bayhead delta facies with variable bioturbation intensity. At or near the river mouth, heterolithic river-dominated successions are more typical. Deposits are overall unburrowed （BI 0-2., but with high burrowing spikes. Ichnogenera are characterized by horizontal, morphologically simple, and facies-crossing structures. The updrift, in contrast, is sourced by a second sediment source and typically consists of laterally continuous sandy beach and shoreface facies. Bioturbation is overall high （BI 3-6） and ichnogenera are healthy and robust, attributable to the Cruziana and Skolithos lchnofacies. Depending on shoreline trajectory and depositional history, facies characteristics of asymmetric deltas preserved in the ancient record, however, can be different from those predicted by the models. Degree of asymmetry is indicated by the asymmetry index （A）, defined as the ratio between the rate of longshore transport at the river mouth and river water discharge. The indexes in symmetric waveinfluenced deltas is less than 2.0, whereas those in asymmetric and deflected deltas are larger than 2.0. Overall the larger the index, the higher the degree of asymmetry. Delta asymmetry concepts and models challenge the traditional definition of deltas and the delta classification scheme, in a hydrocarbon exploration perspective, asymmetric deltas bear very different types of sands and, thus, reservoirs between the updrift and the downdrift. The updrift consists of wellsorted, mature, and laterally continuous homogeneous beach-shoreface reservoirs

关键词： Delta asymmetry asymmetry index longshore drift wave-influenced deltas ichnology

THE SOLVABILITY FOR A CLASS OF SINGULARLY PERTURBED QUASI-LINEAR DIFFERENTIAL SYSTEM

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Acta Mathematica Scientia 2008年第3期28卷 495-500页

作者：莫嘉琪王辉林万涛 department of Mathemtics Anhui Normal University Division of Computational Science E-Institutes of Shanghai Universities at SJTUShanghai 200240China department of Mathematics Huzhou Teachers'CollegeHuzhou 313000China Chinese Academy of Meteorological sciences LASG Institute of Atmospheric PhysicsChinese Academy of Sciences

The solvability for a class of singularly perturbed Robin problem of quasilinear differential system is considered. Using the boundary layer corrective method the formal asymptotic solution is constructed. And using t... 详细信息

关键词： Solvability singular perturbation differential system boundary layer

Analyses of spring mean circulations for major andminor dust storm years in china-Mongolia area

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Research in Cold and Arid Regions 2009年第4期1卷 361-371页

作者： MinHong Song 1,ZhengAn Qian 1,Ying Cai 1,ChungMing Liu 2.1.Cold and Arid Regions Environmental and Engineering Research Institute,Chinese Academy of sciences,lanzhou Gansu {2.,china.2.department of atmospheric sciences,Taiwan university,Taipei 106,china. Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences

To better understand the dust storm (hereafter DS) inducing circulation in the china-Mongolia (CM) DS activity area,the spring mean circulation features and differences on lower levels in three subregions of the CM DS area for the majorandminor-DS years have,as a whole (not partly),been analyzed,utilizing the National Centers for Environmental Prediction and the National Center for atmospheric Research (NCEP/NCAR) reanalyzed gridded data,the observed DS frequency data in the CM area,and the composite analysis *** main conclusions are as follows:(1) Judging from the differences in the DS-inducing systems,dust origins,paths of invading cold air,and main DS-strike areas,the whole CM DS area is roughly divided into the three subre-gions:the East-,Middleand West-CM subregions (in this paper,referred to as E-,M-,and W-CM).(2. In major DSs during spring over the E-CM,the middleand lower-level troughs or cyclones over the Japan Sea and northeastern china (NEC) *** invading cold air along the northeastern (NE) or north by east (NE) path often causes the DS in the E-CM *** nearly the opposite is true inminor DS during spring in E-CM.(3) In the major DS during spring over the M-CM region,the Mongolian troughs or cyclones are the main DS-inducing *** strong invading cold air along the northwestern (NW)or north by west (Nw) path causes the DSs in the M-CM region.(4) In the major DSs during spring over the W-CM region,the South Xinjiang heat lows prevail,the intruding cold air has a western path,and creates the DSs in South Xinjiang.(5) In the past 50 years,the DSs over the M-CM region have had the most severe impact on the preceding three subregions of the CM DS ***,DS activities over all of three regions of the CM area decreased in the past (particularly,over Mand W-CM regions since the *** there existed a short and sudden increasing in E-CM in the years 2.00-2.02.(6) It is circulation changes and desertification evolutions tha

关键词： East-,middleand west-CM subregions major andminor DS during spring DS-inducing system path of invading cold air trend of DS activity changes

Trend,seasonal and diurnal variations of atmospheric CO_2.in Beijing

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Chinese Science Bulletin 2002年第24期47卷 2050-2055页

作者： WANG Yuesi, WANG Changke, GUO Xueqing, LIU Guangren & HUANG YaoLAPC, Institute of atmospheric Physics, Chinese Academy of sciences, Beijing 100083,{2. department of Chemistry, Capital Normal university, Beijing 100037,{2. LAPC Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China department of Chemistry Capital Normal University Beijing China

The concentration of atmospheric CO2.in Beijing increased rapidly at a mean growth rate of 3.7%·a-1 from 1993 to 1995. After displaying a peak of (409.7±2..9) μmol·mol-1 in 1995, it decreased slowly. Both the almost stable anthropogenic CO2.source and increasing biotic CO2.sink contribute to the drop of CO2.concentration from 1995 to 2.00. The seasonal variation of CO2.concentration exhibits a clear cycle with a maximum in winter, averaging (42..8± 2..6)μmol·mol-1, and a minimum in summer, averaging (369.1±6.1)μmol·mol-1. The seasonal variation of CO2.concentration is mainly controlled by phenology. The mean diurnal variation of atmospheric CO2.concentration for a year in Beijing is highly clear: daily maximum CO2.concentration usually occurs at night, but daily minimum CO2.concentration does in the daytime, with a mean diurnal difference more than 34.7μmol·mol-1. It has been revealed that the interannual variations of atmospheric CO2.concentration in winter and autumn regulated the

关键词： atmospheric CO2 annual variation seasonal variation diurnal variation urban environment.

Hierarchical structures in climate and atmospheric turbulence

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Progress in Natural Science:Materials International 2002年第10期 29-34页

作者： SHE Zhensu, FU Zuntao, CHEN Jiong, LIANG Shuang and LIU Shida(1. State Key Laboratory for Studies of Turbulence and Complex Systems, department of Mechanics and Engineering sciences, Peking {2., Beijing 100871, china 2. School of Physics, Peking {2., Beijing 100871, china 3. LAPC, Institute of atmospheric Physics, Chinese Academy of sciences, Beijing 10002., china) State Key Laboratory for Studies of Turbulence and Complex Systems，department of Mechanics and Engineering sciences，Peking {2.，Beijing 100871，china LAPC，Institute of atmospheric Physics，Chinese Academy of sciences，Beijing 10002.，{2. School of Physics，Peking university，Beijing 100871，china State Key Laboratory for Studies of Turbulence and Complex Systems，department of Mechanics and Engineering sciences，Peking {2.，Beijing 100871，china School of Physics，Peking university，Beijing 100871，china

The climatic time series encompass many time scales, forming multi-scale climatic variations and hierarchies. The periods and magnitudes of cooling or warming, especially for extreme climatic events, vary with the time scales. On the other hand, high-frequency atmospheric turbulent motions, which are certainly related to the climatic changes, are also typical multi-scale phenomena. In this paper, certain properties of the fluctuations are examined that are invariant with the change of the time scales. Specifically, the existence of a statistical similarity law is demonstrated in climatic time series and in atmospheric turbulent motions. This is the hierarchical similarity law. Further analyses show that the hierarchical similarity law is a general property of multi-scale fluctuation systems. Therefore, the study on the hierarchical similarity law is important for understanding the inherent universal physical mechanism of complex systems in the atmospheric motions.

关键词： climate multi-scale hierarchical structure atmospheric turbulence.