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Operator constraint principle for simplifying atmospheric dynamical equations

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Chinese Science Bulletin 2001年第12期46卷 1053-1056页

作者： LI Jianping & CHOU Jifan1. National Key Laboratory of atmospheric sciences and Geophysical Fluid Dynamics (LASG), Institute of atmospheric Physics, Chinese Academy of sciences, Beijing 10002., china 2. department of atmospheric sciences, lanzhou university, lanzhou 730000, china National Key Laboratory of atmospheric sciences and Geophysical Fluid Dynamics (LASG) Institute of Atmospheric Physics Chinese Academy of Sciences department of atmospheric {2. Lanzhou University

Based on the qualitative theory of atmospheric dynamical equations, a new method for simplifying equations, the operator constraint principle, is presented. The general rule of the method and its mathematical strictness are discussed. Moreover, the way that how to use the method to simplify equations rationally and how to get the simplified equations with harmonious and consistent dynamics is given.

关键词： simplification operator equation operator constraint principle.

A quasi-geostrophic wavelet-spectrum model for barotropic atmosphere and its numerical solution

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Progress in Natural Science:Materials International 2004年第11期 48-54页

作者： DAI Xingang 1,2.*, WANG Ping 3 and CHOU Jifan 2. (1. Key Laboratory of Regional Climate-Environment for Temperate East Asia, Institute of atmospheric Physics, Chinese Academy of sciences, START Regional Center for Temperate East Asia, Beijing 10002.,{2. 2. department of atmospheric sciences, lanzhou university, lanzhou 730000,{2. 3. College of Physics, Peking university, Beijing 100871,{2.) KeyLaboratoryofRegionalClimate-EnvironmentforTemperateEastAsia InstituteofAtmosphericPhysicsChineseAcademyofSciencesSTARTRegionalCenterforTemperateEastAsiaBeijing100029China CollegeofPhysics PekingUniversity.Beijing100871China departmentofatmospheric{2. LanzhouUniversityLanzhou730000.China

A quasi-geostrophic wavelet-spectrum model of barotropic atmosphere has been constructed by wavelet-Galerkin method with the periodic orthogonal wavelet bases. In this study a wavelet grid-spectrum transform method is designed to decrease the tremendous computation of the nonlinear interaction term in the model, and a two-dimensional Helmholtz equation from the model in a wavelet spectrum form is derived, and a solution with high precision under the periodic boundary condition is obtained. The numerical investigation manifests that the wavelet-spectrum model (WSM) could keep on running for a long time under the forcing of heating and topography. Although its numerical solution is compatible with the grid model (GM), the WSM is of a higher precision and faster convergence rate than GM's. A stationary solution comes forth when the model is forced only by the surface heating, whereas a quasi-periodic oscillation with a period about 15 days appears as considering the topography in the model. The latter oscillation, to some extent, is very similar to the Rossby index cycle of atmosphere over middle and high latitudes.

关键词： plane barotropic atmosphere wavelet-spectrum model wavelet grid-spectrum transform.

Advancement and prospect of short-term numerical climate prediction

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Chinese Science Bulletin 2001年第18期46卷 1497-1502页

作者： CHOU Jifan & XU Ming1. department of atmospheric {2., lanzhou university, lanzhou 730000, china 2. Training Center of Chinese Meteorological Administration, Beijing 100081, china department of atmospheric {2. Lanzhou University Lanzhou China Training Center of Chinese Meteorological Administration Beijing China

The defects of present methods of short-term numerical climate prediction are discussed in this paper, and four challenging problems are put forward. Considering our under developed computer conditions, we should innovate in the approcuch of numerical climate prediction on the basis of our own achievements and experiences in the field of short-term numerical climate prediction. It is possibly an effective way to settle the present defects of short-term numerical climate prediction.

关键词： short-term climate numerical prediction defects innovation.

Effects of sunspot cycle length and CO_2.on air temperature along Qinghai-Xizang railway and air temperature's trend prediction

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Science china Earth sciences 2004年第z1期47卷 131-141页

作者： LI Dongliang, QUO Hui, WANG Wen & WEI LiCold & Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Science, lanzhou 730000, china {2. of atmospheric sciences, lanzhou university, lanzhou 730000, china Cold & Arid Regions Environmental and Engineering Research Institute Chinese Academy of Science Lanzhou China department of atmospheric {2. Lanzhou University Lanzhou China

There are well coherences between annual averaged air temperatures at every meteorological station along the Qinghai-Xizang railway, and its 10-year moving average correlation coefficient is 0.92. Thus, the regional averaged annual mean temperature series along the Qinghai-Xizang railway (Trw) from 1935 to 2.00 are constructed. The investigation is suggested that: Trw had significant responses to the 5-year lagged sunspot cycle length (SCL) and 15-year lagged concentration of atmospheric carbon dioxide (CO2., and the correlation coefficients between them are -0.76 (SCL) and 0.88 (CO2., respectively. The future SCL is predicted by the model of average generated function constructed with its main cycles of 76a, 93a, 108a, 2.5a and 2.5a. The result shows that the SCL would be becoming longer in the first half of the 2.st century, and then it could be becoming shorter in the second half of the 2.st century. Based on the natural change of SCL and the effect of double CO2.concentration, Trw in the 2.st century is forecasted. It could warm up about 0.50℃ in the first half of the 2.st century compared with the last decade of last century. The mean maximum air temperature could be likely about 0.2.℃ in July and from 0.40℃ to 1.10℃ in January. The annual air temperature difference would likely reduce 0.3-1.00℃. The probability of above predictions ranges from 0.64 to 0.73.

关键词： Qinghai-Xizang railway, annual mean air temperature, sunspot cycle length (SCL), atmospheric carbon dioxide concentration (CO2., prediction.

Three-dimensional decomposition method of global atmospheric circulation

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Science china Earth sciences 2008年第3期51卷 386-402页

作者： LIU HaiTao1,2.3, HU ShuJuan4, XU Ming5 & CHOU JiFan6,7 1 State Key Laboratory of Numerical Modeling for atmospheric sciences and Geophysical Fluid Dynamics, Institute of atmospheric Physics, Chinese Academy of sciences, Beijing 10002., china 2.Graduate university of Chinese Academy of sciences, Beijing 100049, china 3 Beijing Climate Center, Beijing 100089, china 4 department of Mathematics, lanzhou university, lanzhou 730000, china 5 Shanghai Typhoon Institute, Shanghai 2.0030, china 6 department of atmospheric sciences, lanzhou university, lanzhou 730000, china 7 china Meteorological Administration Training Center, Beijing 100089, china State Key Laboratory of Numerical Modeling for atmospheric sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Graduate university of Chinese Academy of sciences Beijing China Beijing Climate Center Beijing China department of Mathematics Lanzhou University Lanzhou China Shanghai Typhoon Institute Shanghai China department of atmospheric {2. Lanzhou University Lanzhou China china Meteorological Administration Training Center Beijing China

By adopting the idea of three-dimensional Walker, Hadley and Rossby stream functions, the global atmospheric circulation can be considered as the sum of three stream functions from a global perspective. Therefore, a m... 详细信息

关键词： three-dimensional decomposition of the global atmospheric circulation generalized Walker Hadley and Rossby stream functions existence and uniqueness vertical motion

Computational stability of the forced dissipative nonlinear atmospheric equations

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Chinese Science Bulletin 1999年第10期44卷 949-952页

作者： LI Jianping and CHOU Jifan LASG , Institute of atmospheric Physics , Chinese Academy of sciences , Beijing 100080,{2. department of atmospheric sciences , lanzhou university , lanzhou 730000,{2. Beijing Meteorological College, Beijing 100081,{2. LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China department of atmospheric {2. Lanzhou University Lanzhou China Beijing Meteorological College Beijing China

A new concept of computational quasi-stability (CQS) is introduced to study the computational stability (CS) of the forced dissipative nonlinear (FDN) evolution equations. Based on the concept, the CQS criterion of difference scheme of FDN atmospheric equations is obtained. So it provides the theoretical basis for designing the computational stable difference scheme of FDN atmospheric equations.

关键词： computational stability (CS) computational quasi-stability (CQS) operator equation difference scheme forced dissipative nonlinear (FDN) equations.

An Important Rule-Jeans Rule

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紫金山天文台台刊 1996年第3期15卷 93-97页

作者： Gao Chong-yi department of Physics,lanzhou {2.,lanzhou,730000,china

From theoretical physics,Jeans rule can be derived *** is applicable to the planets,satellites,asteroids and meteoroids in the solar *** condition satisfying Jeans rule,is just the necessary condition for a given spec... 详细信息

关键词： An Important Rule-Jeans Rule net

Debating about the climate warming

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Progress in Natural Science:Materials International 2006年第1期16卷 1-6页

作者： WANG Shaowu1, LUO Yong2. ZHAO Zongci2. DONG Wenje2.and YANG Bao3 (1.department of atmospheric {2., School of Physics, Peking university, Beijing 100871, china 2. Laboratory for Climate Studies, china Meteorological Administration, Beijing 100081, china 3. Institute of Cold and Arid Regions Environmental and Engineering, Chinese Academy of {2., lanzhou 730000, china) department of atmospheric {2. School of Physics Peking University Beijing 100871 China

Debating about the climate warming is reviewed. Discussions have focused on the validity of the temperature reconstruction for the last millennium made by Mann et al. Arguments against and for the reconstruction are introduced. Temperature reconstructions by other authors are examined, including the one carried out by Wang et al. in 1996. It is concluded that: (1) Ability of reproducing temperature variability of time scale less than 10 a is limited, so no sufficient evidence proves that the 1990s was the warmest decade, and 1998 was the warmest year over the last millennium. (2. All of the temperature reconstructions by different authors demonstrate the occurrence of the MWP (Medieval Warm Period) and LIA (Little Ice Age) in low frequency band of temperature variations, though the peak in the MWP and trough in LIA varies from one reconstruction to the others. Therefore, terms of MWP and LIA can be used in studies of climate change. (3) The warming from 1975 to 2.00 was significant, but we do not know if it was the strongest for the last millennium, which needs to be proved by more evidence.

关键词： climate warming MWP LIA the 2.th century.

Progress in studies of the climate of humid period and the impacts of changing precession in early-mid Holocene

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Progress in Natural Science:Materials International 2008年第12期18卷 1459-1464页

作者： Jianbin Huang~a Shaowu Wang~a Xinyu Wen~a Bao Yang~b a department of atmospheric {2.,School of Physics,Peking university,Beijing 100871,china b Laboratory for Desert and Desertification,Cold and Arid Regions Environmental and Engineering Research Institute,Chinese Academy of {2.,lanzhou 730000,china department of atmospheric {2. School of Physics Peking University Beijing 100871 China Laboratory for Desert and Desertification Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China

Studies on the climate of humid period and the impacts of changing precession in the early-mid Holocene are reviewed in this paper. High-resolution proxy data indicated that the African Humid Period,strong summer monsoon from the Arabian Sea to South Asia, northward migration of ITCZ (lntertropical Convergence Zone) over the northern South America,and the humid period of china appeared in 10.5-5.5 kaBP,10.0-6.0 kaBP,10.5 5.4 kaBP,and 11.0-8.0 kaBP,*** studies proved that summer inso- lation over the Northern Hemisphere increased following the changes of precession in the early Holocene,which increased the land-sea temperature contrasts,intensified the summer monsoon circulation in the Northern Hemisphere,and finally induced a humid climate over the area under the influence of summer ***,modeling results underestimated the increase of precipitation and the degree of northward extension of monsoon rain belt compared with palaeo-environmental *** discrepancies between the modeling results and the palaeo-environmental data may be associated with the changes of North Atlantic circulation,sea ice and veg- etation ***,climate of the humid period was not stable,in which several droughts were inlaid on centennial *** this review,perspectives for further studies of the climate change of the humid period in the early-mid Holocene are also proposed.

关键词： Holocene Humid period Precession Summer monsoon