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加热效应对南海季风低压垂直环流的贡献

气象学报 1989年第3期47卷 364-370页

作者：梁必骐刘四臣中山大学大气科学系

人们对季风低压的研究大多是限于印度季风低压,而对南海季风低压研究甚少。近年来作者用合成法对南海季风低压的结构做了一些研究,同时根据FGGEⅢB资料用涡度方程和扰动动能方程做诊断分析,讨论了南海季风低压的发生发展过程。结果表明... 详细信息

人们对季风低压的研究大多是限于印度季风低压,而对南海季风低压研究甚少。近年来作者用合成法对南海季风低压的结构做了一些研究,同时根据FGGEⅢB资料用涡度方程和扰动动能方程做诊断分析,讨论了南海季风低压的发生发展过程。结果表明:对于南海季风低压的形成和维持,积云对流和环境场的作用有着重要贡献,而斜压不稳定和正压不稳定的贡献很小。

关键词：加热效应南海季风低压垂直环流积云影响机制

Influence of air-sea interaction on SSTA in different spacial scales

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Acta Oceanologica Sinica 1990年第2期9卷 203-217页

作者： Sun Jilin and Zuo Zhongdao department of Physical Oceanography and Marine Meteorology, Qingdao Ocean university, Qingdao, china

-In this paper, the factors for SSTA development in finite sea area of low latitudes are discussed with simpler linearized equations, According to the coupling conditions at the interface of atmosphere and ocean, we studied the horizontal scale relations of air-sea coupled system satisfying the dynamical and thermodynamical requirements, From the fluctuation viewpoint, the relation of horizontal scales and wave numbers are presented for a linear atmosphere-ocean coupled system with the same time scales. At last part of the paper, the state of fluctuations is examined for different sea scales under certain given atmospheric scale with a simpler two-layer coupled model, and some significant results obtained.

关键词： SSTA

PRE-ESTIMATE FOR THE CHANGE OF CLIMATIC VULNERABILITY TO AGRICULTURAL PRODUCTION IN LOESS PLATEAU,china

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Natural Disaster Reduction in china 2003年第4期 38-41页

作者： Hou Yahong 1 and Liu Wenquan 2 (1. department of atmospheric sciences of Nanjing university, Nanjing 210008 2.Chinese Academy of Meteorological sciences, Beijing 100081)

In Loess Plateau, which has a vulnerable ecological condition, the influence of climatic change on agricultural production is great. Based on introducing the relative definitions of vulnerability and evaluations and schemes of climatic vuhnerability to agricultural production, this paper makes a preliminary evaluation on the vulnerable condition in 1997; and by using the relative results of GCM pre\|estimate, it estimates the possible changes of related index of the disaster; and estimates the future possible changes of climatic vulnerability to agricultural production in Loess Plateau. Its evaluation method and pre\|estimate results can provide a certain scientific basis to the decision of departments concerned.

关键词： climatic change vulnerability agricultural production Loess Plateau

ARE THERE INTERANNUAL-TO-DECADAL SCALE OSCILLATIONS ASSOCIATED WITH SEA ICE-THERMOHALINE CIRCULATION INTERACTIONS IN A SIMPLE COUPLED ATMO-SPHERE-OCEAN-SEA ICE MODEL?

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气象科学 2000年第3期20卷 413-426页

作者： Zhaomin Wang Lawrence A.Mysak (department of atmospheric and Oceanic sciences and Centre for Climate and Global Change Research, McGill university,Montreal,Quebec,Canada,H3A 2K6) department of atmospheric and Oceanic sciences and Centre for Climate and Global Change Research McGill UniversityMontrealQuebecCanadaH3A 2K6

A thermodynamic sea ice model is coupled to an annual mean,zonally averaged,one basin ocean thermohaline circulation(THC)model and an energy moisture balance model(EMBM)of the atmosphere in order to investigate the interactions between sea ice and the *** first,the coupled sea ice ocean model is run under mixed boundary conditions(MBCs),which precludes feedbacks from the *** occur on timescales ranging from interannual to decadal and are spatially confined to the sinking(deep convection)region of the *** negative feedback loop that explains these oscillations is essentially the same as proposed by Zhang,Lin and Greatbatch.A scale analysis shows that in this model only the process of deep convection can occur on interannual to decadal timescales,whereas changes in the basin scale THC occur on centennial to millennial *** means that interactions between sea ice and the large scale THC on interannual to decadal timescales are not possible under ***,after the atmosphere model is coupled to the above sea ice ocean model,the above oscillations due to the interactions between sea ice and deep convection are suppressed because of the following sequence of processes(positive feedback loop):when the ice retreats in a fully coupled system,the atmosphere warms up at high latitudes and hence the ice surface temperature increases,which then causes a further ice retreat.

关键词： Decadal acale oscillations Sea ice thermohaline Atmosphere ocean sea ice model

Palaeoclimate simulation of Little Ice Age

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Progress in Natural Science:Materials International 2004年第8期 68-76页

作者： LIU Jian 1, CHEN Xing 2, WANG Sumin 1 and ZHENG Yiqun 1 (1. Nanjing Institute of Geography and Limnology, Chinese Academy of sciences, Nanjing 210008, china 2. department of atmospheric Science, Nanjing university, Nanjing 210093, china) Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China department of atmospheric Science Nanjing University Nanjing 210093 China

Little Ice Age (LIA) is a typical cold climate period in global scope with a profound impact upon human society. In this study, a coupled global atmospheric circulation model including the land processes (AGCM + SSiB) is used to perform the simulation of LIA climate. Under the control of solar radiation reduction mechanism, the decrease of temperature is more obvious in summer than in winter; meanwhile, there is regional difference in the change of winter temperature. But the temperature decrease is the main characteristic of the annual mean temperature. Volcanic dust has an evident effect on the winter temperature decrease, but to a less extent than the solar radiation. The synchronous function caused by the reduction of solar radiation and the increase of optic depth of volcanic dust has a superposed strengthening effect on the temperature decrease in large regions. Promotion of the vegetation cover rate profits the increase of temperature, and vise versa. Certain decrease of solar radiation will favor the increase of summer monsoon precipitation in East Asia. The increase of optic depth of volcanic dust does not have a significant effect on the annual precipitation in most parts of Eurasian continent. The composite effect of the decrease of solar radiation and the increase of volcanic dust makes the summer monsoon precipitation in East china increase, and that in South Asia decrease. Together with vegetation change, the result shows that precipitation increases with the increase of vegetation coverage (e.g. East Asia), and when the vegetation coverage reduces (e.g. North Africa) the precipitation will decrease, too.

关键词： Little Ice Age model simulation East Asia.

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 sciences 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 200, whereas those in asymmetric and deflected deltas are larger than 200. 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

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 241000, china 2. ICEES, Institute of atmospheric Physics, Chinese Academy of sciences, Beijing 100029, china 3. National Natural Science Foundation of china, Beijing 100085, china) 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.

VARIATIONAL ITERATION SOLVING METHOD FOR SEA-AIR OSCILLATOR MODEL OF INTERDECADAL CLIMATE FLUCTUATIONS

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Chinese Geographical Science 2005年第3期 37-40页

作者： MO Jia-qi1, 2, LIN Yi-hua3, WANG Hui4 (1. department of Mathematics,Anhui Normal university,Wuhu 241000,P. R. china 2. Division of Computational Science E-Institutes of Shanghai Universities at Shanghai Jiaotong university,Shanghai 200240,P. R. china 3. Institute of atmospheric Physics,Chinese Academy of sciences,Beijing 100029,P. R. china 4. Chinese Academy of Meteorological sciences,Beijing 100081,P. R.china) department of Mathematics A nhui Normal UniversityWuhu 241000P. R. China Division of Computational Science E-Institutes of Shanghai Universities at Shanghai Jiaotong UniversityShanghai 200240P. R. China Institute of atmospheric Physics Chinese Academy of SciencesBeijing 100029P. R. China Chinese Academy of Meteorological sciences Beijing 100081P. R. China

atmospheric physics is a very complicated natural phenomenon and needs to simplify its basic models for the sea-air oscillator. And it is solved by using the approximate method. The variational iteration method is a simple and valid method. In this paper the coupled system for a sea-air oscillator model of interdecadal climate fluctuations is considered. Firstly, through introducing a set of functions, and computing the variations, the Lagrange multipliers are obtained. And then, the generalized expressions of variational iteration are constructed. Finally, through selecting appropriate initial iteration from the iteration expressions, the approximations of solution for the sea-air oscillator model are solved successively.

关键词： nonlinear variational iteration El Nio-Southern Oscillator model

A Novel Sulfided Mo/C Catalyst for Direct Vapor Phase Carbonylation of Methanol at atmospheric Pressure

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Journal of Natural Gas Chemistry 2003年第1期12卷 31-36页

作者： Feng Pengdepartment of Chemical Engineering, South china university of Technology, Guangzhou 510640, china department of Chemical Engineering South China University of Technology Guangzhou 510640 China

The direct carbonylation of methanol, without any halide in the feed as apromoter, is presented. A series of Mo catalysts supported on activated carbon, γ-Al_2O_3 and SiO_2were prepared. The results show that the support greatly affects the Mo catalyst in the directvapor-phase carbonylation of methanol, and activated carbon is the best supports of the investigatedsupports. In addition, the relationships between adsorptions of NH_3 and CO and carbonylation ofmethanol were investigated. A novel sulfided Mo/C catalyst had high activity and selectivity for thevapor phase carbonylation of methanol to methyl acetate without the addition of a CH_3I promoter tothe feed. The reaction conditions were optimized at a reaction temperature of 573 K, a methanolconcentration of 23 mol% and a carbon monoxide space velocity of 3,000 L/(kg·h). Under theseoptimal conditions a methanol conversion of 50%, carbonylation selectivity of 80 rnol%, andspace-time yield of 8.0 mol/(kg·h) were obtained. The active phase of this novel sulfided Mo/Ccatalyst is the non-crystalline phase, and the active component is present as MoS_(2.5) on thesurface of the activated carbon.

关键词： methanol carbonylation sulfided catalyst molybdenum catalystsupport activated carbon heterogeneous catalysis