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chinese Science Bulletin 2003年第S2期48卷 61-67页

作者： GAO Hui~(1,2), XUE Feng~1 WANG Huijun~1 1. institute of atmospheric physics,{3., Beijing 10002., china 2. Department of atmospheric sciences, Nanjing institute of Meteorology, Nanjing 210044. china chinese Acad Sci Inst Atmospher Phys Beijing 100029 Peoples R China Nanjing Inst Meteorol Dept Atmospher Sci Nanjing 210044 Peoples R China

Both correlation analysis and case study indi-cate that Antarctic oscillation (AAO) is closely related withsummer rainfall in eastern china. When AAO is stronger inboreal spring, especially in May, there is more mei-yu rain-fall in summer with a longer period along the Yangtze andHuaihe River valley. In contrast, there is less rainfall with ashorter period corresponding to a weaker AAO. Besides, ananomalous AAO changes the position and intensity of severalcirculation systems, which are important to summer rainfallalong the Yangtze and Huaihe River valley. Furthermore, theAntarctic sea ice is negatively correlated with the intensity ofAAO with a 6-month leading time. The result in this studyprovides a new method for the prediction of mei-yu.

关键词： Antarctic oscillation interannual variability mei-yu Antarctic sea ice.

CO_2 background concentration in the atmosphere over the chinese mainland

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chinese Science Bulletin 2002年第14期47卷 1217-1220页

作者： WANG Gengchen, WEN Yupu, KONG Qinxin, REN Lixin & WANG Mulininstitute of atmospheric physics,{3., Beijing, 10002., china academy of Meteorological sciences, china Meteorological Administration, Beijing 100086, china institute of atmospheric physics Chinese Academy of Sciences Beijing China academy of Meteorological sciences China Meteorological Administration Beijing China

Based on the long-term monitoring data on CO2 concentration, variation trend and characteristics of CO2 background concentration in the atmosphere over the chinese mainland are analyzed. Results show that the increasing trend of CO2 background concentration in the atmosphere over the chinese mainland has appeared during the period of 1991-2000. The average annual CO2 growth increment is 1.59μL/L, and the average annual CO2 growth rate is 0.44%. Distinct seasonal variations of CO2 background concentration are observed, and the averaged amplitude of CO2 seasonal variations is 10.3.μL/L. Regional variation characteristics of CO2 background concentration in the atmosphere and possible impact of human activities on these variations over the chinese mainland are discussed as well.

关键词： CO2 background concentration chinese mainland CO2 growth rate CO2 seasonal variation CO2 regional variation CO2 variation trend.

Image of local energy anomaly during a heavy rainfall event

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chinese physics B 2017年第11期26卷 565-573页

作者：杨帅左群杰高守亭 Laboratory of Cloud-Precipitation physics and Severe Storms (LACS) Institute of Atmospheric PhysicsChinese Academy of Sciences State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences

A clear and interesting image of local total energy anomaly(EA) is depicted for a heavy rainfall event in this *** the convection development, it exhibits a positive local EA, implying local total energy(TE) experiences heaping up to prepare for the future system development. As the convection grows, it transforms into an opposite spatial modality with negative EA dominant, which means that the local TE is consumed to feed the convection growth in the middle and lower levels. The local total EA has consistent variation regular in intensity with severe weather system evolution. By utilizing the local TE budget equation in variable density fluid, the flux divergence of energy and its components are investigated, which could account for the local TE variation better. To relax the restriction and complexity introduced by identifying sporadic and alternative positive/negative signals of EA, the method taking the absolute-value operator on energy flux divergence is used to further simplify analyses. The derived characteristic signal of absolute EA is clearer and cleaner than ***, the EA could be illustrated based on the active degree of energy supply/consumption in a generalized sense whatever positive or negative anomaly should be it, which could be used easily to identify and even predict the system development for operational application. Note that, although two sets of methodologies are used to define EA herein, they play absolutely different roles in nature throughout the whole context. For example, the taking-perturbation method provides a diagnostic tool to portray a preliminary sketch and to give sufficient necessity of this research, while tendency equation of local TE illuminates more predictive sense and accounts for future local EA related to following system evolution. Therefore, the latter could be a more effective tool to routine usage.

关键词： local energy anomaly energy budget equation heavy rainfall

Variational iteration solving method of a sea-air oscillator model for the ENSO

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Progress in Natural Science:Materials International 2007年第2期17卷 230-232页

作者： MO Jiaqi, LIN Wantao and WANG Hui ( Department of Mathematics, Anhui Normal University, Wuhu 241000, china Division of Computational Science, E-institutes of Shanghai Universities, at SJTU, Shanghai 200240, china LASG, institute of atmospheric physics, chinese academy of sciences, Beijing 10002., china chinese academy of Meteorological sciences, Beijing 100081, china) Department of Mathematics Anhui Normal University Wuhu 241000 China Division of Computational Science E-Institutes of Shanghai Universities at SJTU Shanghai 200240 China LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China chinese academy of Meteorological sciences Beijing 100081 China

A time delay equation for sea-air oscillator model is studied. The aim is to create an asymtotic solving method of nonlinear equation for the ENSO model. And based on a class of oscillators of ENSO model, employing the variational iteration method, the approximate solution of corresponding problem is obtained. It is proven from the results that the method of variational iteration method can be used for analyzing the sea surface temperature anomaly in the equatorial eastern Pacific of the atmosphere-ocean oscillation for ENSO model.

关键词： Nonlinear problem, time delay, El Nino-Southern oscillator model variational iteration.

Radiometric cross-calibration of the CBERS-02 CCD camera with the TERRA MODIS

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Science china(Technological sciences) 2005年第S2期48卷 44-60页

作者： LI Xiaoying1,2,3. GU Xingfa1,3.4, MIN Xiangjun5, YU Tao1,3. FU Qiaoyan5, ZHANG Yong1,2,3.& LI Xiaowen1,3.1. State Key Laboratory of Remote Sensing Science, Jointly Sponsored by the institute of Remote Sensing Applications of chinese academy of sciences and Beijing Normal University, Beijing 100101, china 2. Graduate University of chinese academy of sciences, Beijing 10003., china 3. The Center for National Spaceborne Demonstration, Beijing 100101, china 4. Institut National de la Recherche Agronomique, Climat Sol Environnement, 84914 Avignon, France 5. china Center for Resource Satellite Data and Application, Beijing 10083., china State Key Laboratory of Remote Sensing Science Beijing Normal University Chinese Academy of Sciences Beijing 100101 China Graduate University Chinese Academy of Sciences Beijing 100039 China Center for National Spaceborne Demonstration Beijing 100101 China Institut National de la Recherche Agronomique Climat Sol Environnement 84914 Avignon France china Center for Resource Satellite Data and Application Beijing 100830 China

For the application of the CCD camera, the most important payload on CBERS-02, the key is to provide long-term stable radiometric calibration coefficients. Although the vicarious calibration had been proved successful, it had its limitations such as test site requirement and unsuitable for historical data. Cross-calibration is one of the alternative methods, but it needs synchro surface spectrum to achieve spectral band matching factors. Our effort is to probe the influences on these factors. Simulations with a lot of surface spectrum showed that the factors changed with the viewing geometry, atmospheric condition and surface targets. However, simulating with the same viewing geometry and atmospheric condition, the spectral band matching factors of the same or similar surface targets’ spectrum acquired from different dates and different places would like to be consistent to each other within 1%―5%. Thus, the synchro measurement data can be substituted by the same or similar target from other source. Based on this method, using the MODIS as the reference, the cross-calibration was performed for CCD camera. The research demonstrated that the traditional method with single calibration site was inappropriate for CCD camera, since the offsets for its four spectral bands were not zeros. With four calibration sites, these offsets were obtained. And the camera was detected to degrade with dates based on four times of cross-calibrations.

关键词： CBERS-02 CCD camera cross-calibration the spectral band matching factors.

SIMULATION ON SITE ERRORS'ESTIMATION

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高原气象 1992年第3期11卷 285-293页

作者： Chen Mingli Guo Changming(Lanzhou institute of Plateau atmospheric physics,{3., Lanzhou, Gansu 73.000) 中科院兰州高原大气物理所甘肃兰州

In this paper, using the same simulated conditions that Lopez and Passi (1989) used, the method of Chen et a1.(1991) (CLG’s algorithm) for site error estimation has been performed. The results show that the CLG works well for a four-DF network but still has some shortcomings for a three-DF system. The reason why there is a big difference between a four-DF network and a three-DF network is also discussed and several measures to improve the performance of CLG’s algorithm are suggested. For practice, we have also done the simulated experiment for the Beijing local three-DF network. This is helpful for us to use the data obtained in this network.

关键词： Lightning location system Site errors Cloud-to-ground lightning.

Preliminary results of a regional air-sea coupled model over East Asia

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chinese Science Bulletin 2010年第21期55卷 2295-2305页

作者： LI Tao ZHOU GuangQing institute of atmospheric physics Chinese Academy of Sciences Beijing 100029 China Graduate University of the chinese academy of sciences Beijing 100049 China

We have established a regional air-sea coupled model over East Asia and conducted a 20-year integration to evaluate its performance in reproducing the present *** coupled model consists of RegCM3.and HYCOM controlled by the OASIS3.coupler with resuolution of 60 km for the atmosphere and 3. km for the ocean,*** some other regional air-sea coupled models,a one-way nesting method is employed in the oceanic component and a heat flux adjustment for solar radiation is used to remove an about 2°C cold bias in *** primary analysis for this 20-year integration shows that the coupled model successfully reproduces the main features of the circulations over East Asia,both in the atmosphere and the ocean,including climatology,seasonal and interannual *** are seen in the coupled model compared to the uncoupled one,especially in the simulation of precipitation,the most important element of the East Asian monsoon,although there are still obvious discrepancies that come mainly from the model components *** analyses show that the rainfall simulation benefits from the enhancements of the Northwest Pacific Subtropical High in summer,which leads to the improvement of the moisture flux simula-tion at the middle-lower atmospheric *** results indicate that the regional air-sea coupled model is more suitable for the East Asia monsoon simulation.

关键词：海气耦合模式东亚地区空气西北太平洋副高大气环流海域耦合模型模拟降雨

A new method to prepare clean cuticular membrane from fossil leaves with thin and fragile cuticles

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Science china Earth sciences 2011年第2期54卷 223-227页

作者： WANG Li1,2 & LENG Qin1,3.1 State Key Laboratory of Palaeobiology and Stratigraphy,Nanjing institute of Geology and Palaeontology,chinese academy of {3.,Nanjing 210008,china 2 Graduate School of chinese academy of sciences,Beijing 100049,china 3.Department of Science and Technology,Bryant University,Smithfield RI 02917,USA State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing China Graduate School of chinese academy of sciences Beijing China Department of Science and Technology Bryant University Smithfield USA

Leaf cuticle analysis has long been a powerful tool for fossil plant identification, systematics, and palaeoclimatological recon- struction. In recent decades the application of stomatal frequency data that are relied on precise calculation of stomata on plant fossil cuticles to reconstruct ancient atmospheric CO2 concentration made the preparation of cuticular membrane with sufficient size a critical technique in palaeoclimatological research. However, for plants with originally thin and fragile cuticles, e.g., most deciduous plants, conventional techniques sometimes fail to obtain cuticular membranes with sufficient size, or sometimes unable to recover any. This has largely hampered the usage of fossil cuticle analysis in palaeobotanical and palaeo- climatological research. Here, we describe a new method using clear nail polish as a medium to ＂strengthen＂ the originally thin and fragile cuticles prior to maceration procedures. We demonstrate the method by using middle Eocene Metasequoia fossils that were notorious for the difficulty of recovering large-sized clean cuticular membranes due to their thin and fragile nature. Metasequoia, with well-documented and widely-distributed fossil records since the Late Cretaceous and with a living repre- sentative, 114. glyptostroboides, as a comparative reference, bas been widely used as a model genus for the study of evolution of plants, palaeoclimatological reconstruction, and plant adaptation to climate changes. But its deciduous habit produces thin cuticles and makes the preparation of clean cuticular membranes a tedious process. The new method successfully allows us to recover its delicate cuticular membranes with sufficient sizes for SEM observation and stomatal frequency analysis.

关键词： fossil leaf cuticle Metasequoia new method thin and fragile cuticle SEM observation stomatal frequency CO2

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,{3., Beijing 100083. china Department of Chemistry, Capital Normal University, Beijing 10003., china 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±25.9) 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 2000. The seasonal variation of CO2 concentration exhibits a clear cycle with a maximum in winter, averaging (426.8± 20.6)μmol·mol-1, and a minimum in summer, averaging (3.9.1±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 3..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.

Adjoint method for the optimum planning of industrial pollutant sources

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Science china Earth sciences 2005年第8期48卷 1270-1279页

作者： LIU Feng1,2, HU Fei2 & ZHU Jiang2 1. College of Environmental sciences, Peking University, Beijing 100871, china 2. LAPC, institute of {3. physics, chinese academy of sciences, Beijing 10002., china College of Environmental sciences Peking University Beijing China LAPC Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China

The optimum planning of industrial pollutant sources, which optimizes the economic object without violating environmental constraints, is an important and hard task to be conquered. In this paper, an adjoint method is developed to solve the problem. The penalty function is in-troduced to deal with the environmental inequality constraints, and Lagrange function is con-structed to derive the adjoint equation and the gradient of the object function. In this means, the gradient of the object function can be calculated by solving the adjoint equation, and the infor-mation from the gradient is used to make the object function descend and approach to an optimal solution after some iterations. A two-dimensional, simplified model is used for numerical experi-ments. The theoretical derivations are verified by the results of the experiments. Furthermore, the adjoint method is shown to be of excellent convergence and efficiency, which is adaptive to the fast development of air quality numerical models and super computers.

关键词： optimum planning, industrial pollutant sources, adjoint equation, penalty function, gradient.