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UNIFICATION AND APPLICATIONS OF MODERN OCEANIC/atmospheric DATA ASSIMILATION ALGORITHMS

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Journal of Hydrodynamics 2004年第5期16卷 501-517页

作者： QIAOFang-li ZHANGShao-qing YUANYe-li instituteofOceanography ChineseAcademyofSciencesQingdao266071China geophysicalfluid{2.laboratory PrincetonUniversityPrincetonNJ08542USA keylaboratoryofMarine{2.and{2.modeling TheFirstInstituteofOceanographyStateOceanicAdministrationQingdao266061China

The key mathematics and applications of various modern atmospheric/oceanicdata assimilation methods including Optimal Interpolation (OI), 4-dimensional variational approach(4D-Var) and filters were systematically reviewed and classified. Based on the data assimilationphilosophy, i. e. , using model {2. to extract the observational information, the commoncharacter of the problem, such as the probabilistic nature of the evolution of theatmospheric/oceanic system, noisy and irregularly spaced observations, and the advantages anddisadvantages of these data assimilation algorithms, were discussed. In the filtering framework, allmodern data assimilation algorithms were unified: OI/3D-Var is a stationary filter, 4D-Var is alinear (Kalman) filter and an ensemble of Kalman filters is able to construct a nonlinear *** nonlinear filter such as the Ensemble Kalman Filter (EN-KF), Ensemble Adjustment Kalman Filter(EAKF) and Ensemble Transformation Kalman Filter (ETKF) can, to some extent, account for thenon-Gaussian information of the prior distribution from the model. The flow-dependent covarianceestimated by an ensemble filter may be introduced to OI and 4D-Var to improve these traditionalalgorithms. In practice, the performance of algorithms may depend on the specific numerical modeland the choice of algorithm may depend on the specific problem. However, the unification ofalgorithms allows us to establish a unified test system to evaluate these algorithms, which providesmore insights into data assimilation philosophies and helps improve data assimilation techniques.

关键词： data assimilation oceanic/atmospheric system filtering optimalinterpolation (OI) 4-dimensional variational(4D-Var) approach

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 {2. of {2. modeling for atmospheric sciences and geophysical fluid dynamics, institute of atmospheric physics, chinese academy of sciences,{12., 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 {2. of {2. 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 sciences 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

Development of the universal and simplified soil model coupling heat and water transport

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science China Earth sciences 2008年第1期51卷 88-102页

作者： LI Qian1,2.& SUN ShuFen1 1 state key {2. of {2. modeling for atmospheric sciences and geophysical fluid dynamics, institute of atmospheric physics, chinese academy of sciences,{12., China 2.Graduate University of the chinese academy of sciences, beijing 100049, China state key {2. of {2. modeling for atmospheric sciences and geophysical fluid dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Graduate University of the chinese academy of sciences Beijing 100049 state key {2. of {2. modeling for atmospheric sciences and geophysical fluid dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

It is very important to develop a universal soil model with higher simplicity and more accuracy, which can be widely applied to very general cases such as wet or dry soil, frozen or unfrozen soil and homogeneous or heterogeneous soil. Firstly in this study, based on analysis of both magnitude order and the numerical simulation results, the universal and simplified soil model (USSM) coupling heat and mass transport processes is developed. Secondly, in order to avoid the greater uncertainty caused by the phase change term in numerical iteration process for the model solution obtaining, new version of the universal simplified soil model (NUSSM) is further derived through variables transformation, and accordingly a more efficient numerical scheme for the new version is designed well. The simulation results from the NUSSM agree with the results from more complicated and accurate soil model very well, also reasonably reproduce the observed data under widely real conditions. The new version model, because of its simplicity, will match for the development of land surface model.

关键词： universal and simplified soil model coupled heat and mass transport processes frozen soil arid soil heterogeneous soil

Spring Arctic Sea Ice as an Indicator of Eurasian Summer and North American Rainfall

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Spring Arctic Sea Ice as an Indicator of Eurasian Summer and...

Influences of Typhoon Chanchu on the 2.06 South China Sea summer monsoon onset

第2.届中国气象学会年会

作者： MirongSong Jiping Liu state key {2. of {2. modeling for atmospheric sciences and geophysical fluid dynamics,institute of atmospheric {12.,chinese academy of sciences,beijing,10002.,China

Associations between spring Arctic sea ice concentrations（SIC） and 1) Eurasian and 2. North American summer rainfall are examined using singular value *** show that a reduced SIC in the north Atlantic and Pacific sectors of the Arctic and an enhanced SIC in much of the central Arctic Basin and Beaufort Sea are accompanied by 1) dry conditions over northern and eastern Europe,Mongolia,and northern and central China,and wet conditions over much of Siberia,western and southern Europe,and Middle East,and 2. dry conditions over the western United states,the northern Great Plains,the Midwest,westernmost Canada,and central and eastern Greenland,and wet conditions over the southern United states,Alaska,northern Canada,and western *** circulation anomalies associated with the SIC variability show wave train structures,which are quite persistent from spring to summer and responsible for the identified covariability between the spring Arctic SIC and 1) Eurasian and 2. North American summer *** relationships suggest a potential long‐term outlook for the 1) Eurasian and 2. North American summer rainfall as the decline of the spring sea ice in the north Atlantic and Pacific sectors of the Arctic is expected to continue associated with greenhouse warming.

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Influences of Typhoon Chanchu on the 2006 South China Sea su...

Perturbed solution of sea-air oscillator for the El Nino/ La Nina-Southern Oscillation mechanism

“2.10年北京气象学会中青年优秀论文评选”学术研讨会

作者： Jiangyu Mao and Guoxiong Wu 1 state key {2. of {2. modeling for atmospheric sciences and geophysical fluid dynamics(LASG),institute of atmospheric {12.,chinese academy of sciences,beijing,China.

This study reveals some unique features associated with the impact of Typhoon Chanchu on the South China Sea(SCS) summer monsoon(SCSSM) onset in *** Typhoon Chanchu entering the SCS in mid-May, southwesterlies were induced over the SCS and its upstream region due to a thermally forced Rossby wave response,leading to a reversal of low-level winds and a positive meridional temperature gradient(MTG) in the upper troposphere over the *** Chanchu thus acted as an immediate trigger for the SCSSM onset,and the onset date was suggested to occur in the third pentad of *** the typhoon landed in the coast of southern China,it still contributed to the establishment of the SCSSM due to warming the air column over the northern SCS,resulting in a persistent positive MTG with the ridge surface tilting northward.

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Acta Oceanologica Sinica 2009年第3期28卷 1-4页

作者： ZHOU Xianchun LIN Yihua WANG Hui MO Jiaqi College of Electronic and Information Engineering Nanjing University of information Science and Technology Nanjing 210044 China Division of Computational science E-Institutes of Shanghai Universities at SJTU Shanghai 200240 China state key {2. of {2. modeling for atmospheric sciences and geophysical fluid dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China National Marine Environmental Forecastins Center Beijing 100081 China Department of Mathematics Anhui Normal University Wuhu 241000 China

A class of coupled system of the E1 Nino/La Nina-Southern Oscillation （ENSO） mechanism is studied. Using the perturbed theory, the asymptotic expansions of the solution for ENSO model are obtained and the asymptotic... 详细信息

关键词： nonlinear perturbation theory E1 Nino/La Nina-Southern Oscillation model

ENVIRONMENTAL AND TOPOGRAPHIC INFLUENCES ON atmospheric INTERNAL SHIP WAVES

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Journal of Hydrodynamics 2008年第4期20卷 440-447页

作者： ZANG Zeng-liang PAN Xiao-bin ZHANG Ming Department of Martial Meteorology Institute of Meteorology PLA University of Science and TechnologyNanjing 211101 China state key {2. of {2. sciences and geophysical fluid dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

A theoretical model was used to investigate the influences of environmental and topographic parameters on the atmospheric three-layer internal ship waves. The results show that both the wavelength and the wedge angle decrease with an increase in the Scorer parameter, and the rate of changes in the wavelength and wedge angle are also alike. The results also show that the wedge angle decreases with an increase in the width of mountain, but the wavelength varies little with it. It is suggested that the wedge angle is determined by the ratio of the wavelength to the scale of the mountain. Besides, numerical sensitivity experiments were performed to test the former numerical experiments. The simulated results are consistent with the analytical results.

关键词： Scorer parameter topographic parameter atmospheric internal ship waves numerical simulation

INTERDECADAL CHANGE OF KOREA LANDFALLING TROPICAL CYCLONE FREQUENCY AND ITS POSSIBLE ASSOCIATION WITH PDO

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Tropical Cyclone Research and Review 2016年第3期5卷 58-71页

作者： Jae-Won Choi Yumi Cha Hae-Dong Kim state key {2. of {2. modeling for atmospheric sciences and geophysical fluid dynamics,institute of atmospheric {12.,chinese academy of sciences National institute of Meteorological sciences Department of Global Environment,Keimyung University state key {2. of {2. modeling for atmospheric sciences and geophysical fluid dynamics Institute of Atmospheric PhysicsChinese Academy of Sciences National institute of Meteorological sciences Department of Global Environment Keimyung University

The present study verified that Korea landfalling tropical cyclone(TC) frequency was rapidly increased since 1981 through the statistical change-point analysis. The increase was due to the formation of anomalous southerlies around Korea from the low latitude ultimately because anomalous cyclone was strengthened in East Asia continent due to the movement of western North Pacific subtropical high(WNPSH) to the east whereas anomalous anticyclone was strengthened in the western North Pacific. The anomalous southerlies played a role in steering flow that moved TCs generated in the subtropical western North Pacific to Korea. In order to determine the cause of strengthening of anomalous cyclone in East Asia continent, a snow depth during the preceding spring(March-May) was analyzed. The analysis result showed that most regions in East Asia had lower snow depth than that before 1981. Thus, anomalous cyclone can be developed in the region during summer due to heating in East Asia continent, which was started from the preceding spring, thereby forming a steering flow of anomalous southerlies that can move TCs into Korea. Furthermore, a correlation analysis between Pacific Decadal Oscillation(PDO) and Korea landfalling TC frequency verified that negative correlation was somewhat stronger after 1981.

关键词： Korea tropical cyclone statistical change-point analysis snow depth Pacific Decadal Oscillation

Weakening Trend in the atmospheric Heat Source over the Tibetan Plateau during Recent ***Ⅱ:Connection with Climate Warming

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Weakening Trend in the Atmospheric Heat Source over the Tibe...