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Three-dimensional variational data assimilation implemented in numerical modeling for Wuhan torrential rain in July 1998

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Progress in Natural Science:Materials International 2002年第6期 47-50页

作者： ZHANG Xin , wang bin, ji zhongzhen and LIN Wantao(lasg, institute of atmospheric physics, chinese academy of sciences, beijing 100029, china) lasg Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

On July 20-21, 1998, a torrential rain with 24-hour rainfall of 286mm occurred in Wuhan, Hubei Province of china. In this study, a three-dimensional variational data assimilation system developed at the Fifth-Generation Pennsylvania State University/National Center for atmospheric Research Mesoscale Model ( MM5 ) along with conventional rawinsonde sounding and surface observation is used for modeling the heavy rain. It successfully incorporates observational data of temperature, humidity and wind, and provides an optimal analysis being in favor of the formation of heavy rain. The 24-hour rainfall predicted by the new scheme is 109 mm rather tban 2.5 mm forecasted by control experiment. Furthermore, the forecasted accuracy of location and time-variation of hourly rainfall reproduced by this model is also improved.

关键词： variational data assimilation torrential rain numerical modeling.

The relationship between short-range motion of atmosphere and ocean and conservative and nonconservative scheme

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Science Bulletin 2003年第10期48卷 999-1001页

作者： LIN Wantao, ji zhongzhen & wang bin lasg,institute of atmospheric physics, chinese academy of sciences, beijing 100029, china lasg Institute of Atmospheric Physics Chinese Academy of Sciences China

Taking one-dimensional shallow water wave equation as an example, a comparative analysis on the computational stability related to the short-range motion of atmosphere and ocean is carried out for the conservative and nonconservative scheme, and it is pointed out that the computational stability of conservative scheme is absolutely different from that of the nonconservative scheme. The relationship between the short-range motion of atmosphere and ocean and the conservative and nonconservative scheme is further discussed. The constructed conservative scheme is proved to be stable by the numerical experiment for the short-range motion of atmosphere and ocean while the CTCS scheme is unstable. So that the conservative scheme for the solution of this kind of problem has more advantages.

关键词： short-range motion of atmosphere and ocean conservative scheme nonconservative scheme computational stability.

A new method for constructing total energy conservation algorithms

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Progress in Natural Science:Materials International 2003年第1期13卷 59-62页

作者： ZHAO Ying , ji zhongzhen, YANG Hongwei and wang bin (1. lasg, institute of atmospheric physics, chinese academy of sciences, beijing 100029, china 2. institute of Science, PLA University of Science and Technology, Nanjing 211101, china) chinese Acad Sci Inst Atmospher Phys LASG Beijing 100029 Peoples R China PLA Univ Sci & Technol Inst Sci Nanjing 211101 Peoples R China

Abstract Based on a basic rule for the research on numerical methods which requires that the properties of the original problemshould be preserved as much as possible under discretization, a new method for constructing total energy conservation algorithms is pre-sented. By this method, all kinds of implicit schemes with energy conservation laws including many classical conservation schemes can beconstructed from a kind of special function. Also, the concrete criterion for judging total energy conservation schemes is given. Numericaltests show that these new schemes are effective.

关键词： total energy conservation difference scheme quasi-antisymmetric operator norm-preserving operator.

Design of a new dynamical core for global atmospheric models based on some efficient numerical methods

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Science china Mathematics 2004年第z1期47卷 4-21页

作者： wang bin, WAN Hui, Jl zhongzhen, ZHANG Xin, YU Rucong, YU Yongqiang & LIU HongtaoState Key Laboratory of Numerical Modeling for atmospheric sciences and Geophysical Fluid Dynamics, institute of atmospheric physics, chinese academy of sciences, beijing 100029, china Department of Computational Mathematics, academy of Mathematics and System sciences, Peking University, beijing 100871, china chinese Acad Sci Inst Atmospher Phys State Key Lab Numer Modeling Atmospher Sci & Geop Beijing 100029 Peoples R China Peking Univ Acad Math & Syst Sci Dept Computat Math Beijing 100871 Peoples R China

A careful study on the integral properties of the primitive hydrostatic balance equations for baroclinic atmosphere is carried out, and a new scheme todesign the global adiabatic model of atmospheric dynamics ispresented. This scheme includes a method of weighted equal-areamesh and a fully discrete finite difference method with quadraticand linear conservations for solving the primitive equationsystem. Using this scheme, we established a new dynamical corewith adjustable high resolution acceptable to the availablecomputer capability, which can be very stable without anyfiltering and smoothing. Especially, some important integralproperties are kept unchanged, such as the anti-symmetries of thehorizontal advection operators and the vertical convectionoperator, the mass conservation, the effective energy conservationunder the standard stratification approximation, and so on. Somenumerical tests on the new dynamical core, respectively regardingits global conservations and its integrated performances inclimatic modeling, incorporated with the physical packagesfrom the Community atmospheric Model Version 2 (CAM2) of NationalCenter for atmospheric Research (NCAR), are included.

关键词： dynamical core, equal-area mesh, anti-symmetry, effective energy conservation.

A new method for judging the computational stability of the difference schemes of nonlinear evolution equations

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chinese Science Bulletin 2000年第15期45卷 1358-1361页

作者： LIN Wantao Jl zhongzhen wang bin YANG Xiaozhong State Key Laboratory of Numerical Modeling for atmospheric Science and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China North china Electric Power University Beijing 102206China

For the non-conservative difference schemes of nonlinear evolution equations with aperiodic boundary conditions, taken one-dimensional nonlinear advection equation as an example, a new method for judging the computational stability is given. It is proved to be practical and effective through several numerical examples. The stability criteria obtained by this method are really the necessary conditions of computational stability.

关键词： nonlinear evolution equation difference scheme computational stability heuristic analysis.

Performance of a Parallel Finite Difference atmospheric General Circulation Model

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Advances in atmospheric sciences 2001年第6期18卷 1175-1184页

作者：张昕王斌季仲贞 lasg Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 P.R. China

A new version of the institute of atmospheric physics (IAP) 9-Layer (9L) atmospheric general circulation model (AGCM) suitable for Massively Parallel Processor (MPP) has been developed. This paper presents the principles of the parallel code design and examines its performance on a variety of state-of-the-art parallel computers in china. Domain decomposition strategy is used to achieve parallelism that is implemented by Message Passing Interface (MPI). Only the one dimensional domain decomposition algorithm is shown to scale favorably as the number of processors is increased.

关键词： IAP 9L AGCM domain decomposition parallel speedup and efficiency

Construction of Explicit Quasi-complete Square Conservative Difference Schemes of Forced Dissipative Nonlinear Evolution Equations

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Advances in atmospheric sciences 2001年第4期18卷 604-612页

作者：林万涛季仲贞王斌 State Key Lab. Numer. Modeling A. Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China institute of Physical Ocean Qingdao Ocean University Qingdao 266003 China

Based on the forced dissipetive nonlinear evolution equations for describing the motion of atmosphere and ocean, the computational stability of the explicit difference schemes of the forced dissipotive nonlinear atmospheric and oceanic equations is analyzed and the computationally stable explicit complete square conservative difference schemes are constructed. The theoretical analysis and numerical experiment prove that the explicit complete square conservative difference schemes are computationally stable and deserve to be disseminated.

关键词： Forced dissipative nonlinear evolution equation Explicit quasi-complete square conservative difference scheme Computational stability

Computational Stability of the Explicit Difference Schemes of the Forced Dissipative Nonlinear Evolution Equations

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Advances in atmospheric sciences 2001年第3期18卷 413-417页

作者：林万涛季仲贞王斌 lasg Institute of Atmospheric Physics Chinese Academy of Sciences 100029 Beijing

The computational stability of the explicit difference schemes of the forced dissipative nonlinear evolution equations is analyzed and the computational quasi-stability criterion of explicit difference schemes of the forced dissipative nonlinear atmospheric equations is obtained on account of the concept of computational quasi-stability, Therefore, it provides the new train of thought and theoretical basis for designing computational stable difference scheme of the forced dissipative nonlinear atmospheric equations. Key words Computational quasi-stability - Computational stability - Forced dissipative nonlinear evolution equation - Explicit difference scheme This work was supported by the National Outstanding Youth Scientist Foundation of china (Grant No. 49825109), the Key Innovation Project of chinese academy of sciences (KZCX1-10-07), the National Natural Science Foundation of china (Grant Nos, 49905007 and 49975020) and the Outstanding State Key Laboratory Project (Grant No. 40023001).

关键词： Computational quasi-stability Computational stability Forced dissipative nonlinear evolution equation Explicit difference scheme

太原市冬季大气PM_(2.5)中硫酸盐污染特征及其形成机制研究

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环境科学学报 2024年第9期44卷 54-66页

作者：温晓娅崔阳郭利利何秋生高建荣李永麒李滨吉东生王跃思太原科技大学环境与资源学院太原030024 山西职业技术学院材料环境工程系太原030006 山西省太原生态环境监测中心太原030002 中国科学院大气物理研究所大气边界层物理和大气化学国家重点实验室北京100029

为更好地研究太原市冬季大气细颗粒物(PM_(2.5))中硫酸盐(SO_(4)^(2-))的污染特征及形成机制,于2020年1月采用在线设备对小时分辨率的PM_(2.5)及其化学组分(水溶性离子、金属元素)、气态污染物进行观测,分析了不同污染水平下SO_(4)^(2-... 详细信息

为更好地研究太原市冬季大气细颗粒物(PM_(2.5))中硫酸盐(SO_(4)^(2-))的污染特征及形成机制,于2020年1月采用在线设备对小时分辨率的PM_(2.5)及其化学组分(水溶性离子、金属元素)、气态污染物进行观测,分析了不同污染水平下SO_(4)^(2-)变化特征,评估了不同形成机制对硫酸盐形成的贡献.结果表明,观测期间太原市ρ(PM_(2.5))平均值为(108.7±72.1)µg·m-3,SO_(4)^(2-)、NO_(3)-和NH_(4)^(+)在PM_(2.5)中的占比分别为18.0%±7.9%、16.8%±4.9%和13.1%±3.5%.清洁天、污染天和严重污染天ρ(SO_(4)^(2-))分别为(9.2±5.3)、(17.9±9.2)和(46.3±17.7)µg·m-3,污染天(0.33)和严重污染天(0.51)硫氧化率(SOR,n(SO_(4)^(2-))/(n(SO_(4)^(2-))+n(SO_(2))))明显高于清洁天(0.26).SOR与RH呈显著正相关(r=0.65,p<0.05),与O_(x)(O_(x)=O_(3)+NO_(2))相关性较弱(r=0.10,p<0.05),表明SO_(4)^(2-)主要来源于液相和非均相反应.观测期间pH范围为4.0~4.7,pH影响的敏感性分析显示Mn表面催化和H2O_(2)途径主导硫酸盐的形成.污染案例分析表明硫酸盐产生速率范围为1.5~7.1μg·m^(-3)·h^(-1),数值计算结果显示Mn表面催化和H_(2)O_(2)途径对SO_(4)^(2-)产生的平均贡献分别为37.7%和36.0%.

关键词： PM_(2.5) 硫酸盐在线监测形成机制太原