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ROSSBY WAVES WITH THE CHANGE OF β

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Applied Mathematics and Mechanics(English Edition) 1992年第1期13卷 39-49页

作者：刘式适谭本馗 dept. of Geophysics Peking University Beijing dept. of atmospheric Sciences Nanjing University

In this paper, the change of the Rossby parameter β with latitude is considered and the parameter γ≡-dβ/dy=2Ωsinφ/a2 is introduced and the β-plane approximation is extended into f=f0+β0y-γ0y2/2 which includes the parameter γ . Such approximation closes further to practice especially in the high latitude regions. We give emphasis to the research of the effect of the parameter γ on the Rossby waves. It is seen that the effect of the parameter γ is remarkable in the high latitude regions. It can produce the Rossby waves caused by the pure parameter γ. And the phase speed formula of Rossby waves with the change of β is generally given, which is degenerated into the well-known Rossby formula when γ0=0. The researches also point out that when the change of β is regarded, even if the basic current u¯ is a linear function of y the unstable modes can also take place. However, the parameter γ usually plays a stable part in the Rossby waves and it does affect the longitudinal scale and the structure of constant phase lines (trough-ridge lines) of Rossby waves and slow down the growing or decaying of Rossby waves.

关键词： Rossby waves Rossby parameter parameter γ

Nonlinear Stability Analysis of the Zonal Flows at Middle and High Latitudes

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Advances in atmospheric Sciences 1999年第4期16卷 569-580页

作者：穆穆吴永辉唐谟智柳海燕 LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing dept. of atmospheric Sciences University of Illinois Urbana USA

An attempt has been made to apply Arnold type nonlinear stability criteria to the diagnostic study of the persistence (stability) or breakdown (instability) of the atmospheric flows. In the case of the blocking high, the cut-off low and the zonal flow, the relationships of the geostrophic stream function versus the potential vorticity of the observed atmosphere are analyzed, which indicates that Arnold second type nonlinear stability theorem is more relevant to the observed atmosphere than the first one. For both the stable and unstable zonal flows, Arnold second type nonlinear stability criteria are applied to the diagnosis. The primary results show that our analyses correspond well to the evolution of the atmospheric motions. The synoptically stable zonal flows satisfy Arnol′d second type nonlinear stability criteria; while the synoptically unstable ones violate the nonlinear stability criteria.

关键词： Zonal flow Quasi-geostrophic Nonlinear stability Persistence

Numerical study of rapid cyclogenesis over sea

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Acta Oceanologica Sinica 1989年第1期8卷 51-62页

作者： Du Jun and Yu Zhihao Department of atmospheric Sciences, Nanjing University, Nanjing, China dept. of atmospheric Sciences Nanjing Univ Nanjing China. China

A five-layer primitive equation model was used in the study of rapid cyclogenesis over sea. The numerical simulations show that'the Tibetan Plateau, large-scale baroclinicity and heat flux from the sea surface are the three important agents to produce cyclonic vorticity along the east coast of China. The diagnostic computation of a 24 h control simulation indicates that the nonlinear vorticity advec-tion, baroclinicity and diabatic heating are also responsible for the development of the extratropical cyclones over seas.

关键词： Numerical study of rapid cyclogenesis over sea over

A comparison analysis between developed and undeveloped depressions over the South China Sea

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Acta Oceanologica Sinica 1989年第2期8卷 199-208页

作者： Liang Biqi Zhang Qiuqing Department of atmospheric Sciences, Zhongshan University, Guangzhou, China National Research Center for Marine Environment Forcasts, Beijing, China dept. of atmospheric Sciences Zhangshan Univ. Guangzhou China. China

-- In this paper, by using two sets of composite data of developed and undeveloped depressions over the South China Sea, we analyze and compare the dynamic structures, the heating fields and the vorticity budget residuals of two different types of depressions. Our conclusions are as follows:The two types of depressions are similar in thermodynamical and dynamical structures. The main differ ences are : in the high layer of developed depression there is a divergence field, with a center near the zero line of vertical wind shear, and over undeveloped depression, the divergence field is weaker and the vertical wind at its center is greater than 5 m s-1. The thermodynamical field of the former is asymmetrical and that of the latter is quasi - symmetrical. As far as the dynamics structure is concerned, the convergence in the lower layer and the difference of divergence between the upper and lower layers of developed depression is three tmies larger than that of undeveloped depression. The upward motion and heating field at the center of developed depression is also stronger than that of undeveloped *** vorticity budget of the two types of depressions is mainly determined by the divergence term, the vorticity advection term and the vertical transport term. The residual term is also *** principal contribution comes from the divergence term . This is more significant for developed depression than for undeveloped depression.

关键词： over A comparison analysis between developed and undeveloped depressions over the South China Sea

TURBULENCE IN BROKEN LEE WAVES

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Acta Mechanica Sinica 1993年第3期9卷 210-222页

作者：齐瑛傅抱璞 Institute of Mechanics Chinese Academy of Sciences Beijing China 100080 dept. of atmospheric Sciences Nanjing University Nanjing China 210008

In this paper, the waves' breaking in the lee waves is successfully simulated by the atmospheric mesoscale numerical model with a second-order tur- bulent closure. It is further proved that the turbulence in the wave-breaking region plays the role of intense mixing for the average field, which leads to the trapping of upward propagating waves and thus promotes the development of the downslope wind. The turbulent structure in the wave-breaking region is discussed and the fol- lowing conclusions are obtained: (1) In the wave-breaking region, the turbulent heat fluxes transfer from inside to outside and the turbulent momentum fluxes transfer from outside to inside. (2) In the wave-breaking region, the turbulent energy mainly comes from the wind shear and the buoyancy promotes the turbulent development only in part of the region. (3) In the upper part of the wave-breaking region, the turbulent momentum fluxes behave as a counter-gradient transfer. (4) The turbulent mixing in the wave-breaking region is non-local.

关键词： wave breaking turbulence second-order moment

The effects of different sea surface temperature distributions over the western Pacific on the summer monsoon properties

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Acta Oceanologica Sinica 1993年第4期12卷 535-547页

作者： Qian Yongfu Department of atmospheric Sciences, Nanjing University, Nanjing 210008, China dept. of atmospheric Sciences Nanjing Univ. Nanjing 21008 China. China

A modified and improved primitive equation numerical model with p-sigma incorporated vertical coordinates is used to simulate the effects of different sea surface temperature distributions over the western Pacific on the summer monsoon properties. The different sea surface temperature (SST) distributions are automatically generated in the time integrations by using two different SST models, one of which is called the deep ocean model (DOM) and the other the shallow ocean model (SOM). The SST generated by the DOM has the distribution pattern of the initial SST which is similar to the pattern in the cold water years over the western Pacific, while the SST generated by the SOM has the pattern similar to that in the warm water years. The differences between the experimental results by using DOM and SOM are analyzed in detail. The analyses indicate that the most basic and important characteristics of the summer monsoon climate can be simulated successfully in both experiments, that means the climatic properties in the monsoonal climate regions are mainly determined by the seasonal heating, the contrast between the land and the sea, the topography, and the physical properties of the underlying surfaces. However, the differences between the two experiments tell us that the climatic properties in the summer monsoon regions in the cold water year and the warm water year do differ from each other in details. In the warm water year, the thermal contrast between the land and the sea becomes weaker. Over the warm water area, the upward motions are induced and the dynamical conditions favorable for the convective activities are formed, the Somali low-level cross equatorial current is somewhat weakened, while the cross equatorial currents, east of 90°E, are strongly strengthened, the precipitation amount in the tropical regions largely increases, and the precipitation over the coastal regions increases, too. However the precipitation over the southeast China and its coastal area d

关键词： Sea surface temperature anomaly monsoon climate modelling computational models of SST

Geostrophic Wave Circulations(English edition)

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Advances in atmospheric Sciences 1995年第2期12卷 259-260页

作者： Yong L.McHall(dept.of Earth,atmospheric and Planetary Sciences,MITPublished by China Meteorological Press) dept. of Earth Atmospheric and Planetary Sciences MIT Published by China Meteorological Press USA

ＧｅｏｓｔｒｏｐｈｉｃＷａｖｅＣｉｒｃｕｌａｔｉｏｎｓ（Ｅｎｇｌｉｓｈｅｄｉｔｉｏｎ）ＹｏｎｇＬ．ＭｃＨａｌｌ（Ｄｅｐｔ．ｏｆＥａｒｔｈ，ＡｔｍｏｓｐｈｅｒｉｃａｎｄＰｌａｎｅｔａｒｙＳｃｉｅｎｃｅｓ，ＭＩＴＰｕｂｌ... 详细信息

ＧｅｏｓｔｒｏｐｈｉｃＷａｖｅＣｉｒｃｕｌａｔｉｏｎｓ（Ｅｎｇｌｉｓｈｅｄｉｔｉｏｎ）ＹｏｎｇＬ．ＭｃＨａｌｌ（Ｄｅｐｔ．ｏｆＥａｒｔｈ，ＡｔｍｏｓｐｈｅｒｉｃａｎｄＰｌａｎｅｔａｒｙＳｃｉｅｎｃｅｓ，ＭＩＴＰｕｂｌｉｓｈｅｄｂｙＣｈｉｎａＭｅｔｅｏ...

关键词： Wave English edition Geostrophic Wave Circulations

Numerical Experiment for the Impact of the Ozone Hole over Antarctica on the Global Climate

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Advances in atmospheric Sciences 1998年第3期15卷 18-29页

作者：陈月娟张弘毕训强 dept. of Earth and Space Sciences Univ. of Science & Technology of China Hefei Institute of atmospheric Physics Chinese Academy of Sciences Beijing

A numerical experiment has been carried out with IAP (Institute of atmospheric Physics) 9-layer general circulation model to investigate the influence of the Antarctic Ozone Hole on the global climate. The results show that the changes of total amount of ozone over higher latitude and polar region of the Southern Hemisphere affect not only the climate in the Southern Hemisphere, but also that in the Northern Hemisphere significantly. In the next spring, although the total amount of ozone over Antarctica has returned to the normal value, the influences of Ozone Hole still exist. 

关键词： Antarctic Ozone Hole Climate Numerical simulation

Investigation on the Formation of Herringbone Structure in TypeⅡSolar Radio Bursts

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Research in Astronomy and Astrophysics 2023年第5期23卷 101-109页

作者： Z.Z.Abidin A.N.Zulkiplee V.Epin F.A.M.Pauzi Radio Cosmology Research Lab Physics Dept.Faculty of ScienceUniversity of MalayaKuala LumpurMalaysia

We report detailed observation of the“herringbone”of a Type II solar radio burst that occurred on 2010 November *** from the Space Weather Prediction Center,National Oceanic and atmospheric Administration,e-CALLISTO,and Nan?ay Radio Heliograph are *** determine the brightness temperature and degree of circular polarization of the“herringbone”*** between the physical parameters and the“herringbone”are *** on the relationship,this is the first study that suggested this“herringbone”was generated through fundamental plasma.

关键词： Sun activity-Sun corona-Sun coronal mass ejections(CMEs)-Sun magnetic fields-Sun radio radiation