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Variations in Wave Energy and Amplitudes along the Energy Dispersion Paths of Nonstationary Barotropic Rossby Waves

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Advances in Atmospheric Sciences 2021年第1期38卷 49-64页

作者： Yaokun LI jiping chao Yanyan KANG College of Global Change and Earth System Science Beijing Normal UniversityBeijing 100875China National Marine Environmental Forecasting Center Beijing 100081China Beijing Meteorological Observatory Beijing 100089China

The variations in the wave energy and the amplitude along the energy dispersion paths of the barotropic Rossby waves in zonally symmetric basic flow are studied by solving the wave energy equation,which expresses that the wave energy variability is determined by the divergence of the group velocity and the energy budget from the basic *** results suggest that both the wave energy and the amplitude of a leading wave increase significantly in the propagating region that is located south of the jet axis and enclosed by a southern critical line and a northern turning *** leading wave gains the barotropic energy from the basic flow by eddy *** amplitude continuously climbs up a peak at the turning latitude due to increasing wave energy and enlarging horizontal scale(shrinking total wavenumber).Both the wave energy and the amplitude eventually decrease when the trailing wave continuously approaches southward to the critical *** trailing wave decays and its energy is continuously absorbed by the basic ***,both the wave energy and the amplitude oscillate with a limited range in the propagating region that is located near the jet axis and enclosed by two turning *** the leading and trailing waves neither develop nor decay *** jet works as a waveguide to allow the waves to propagate a long distance.

关键词： barotropic Rossby waves energy dispersion wave ray theory wave energy amplitude

Variations in Amplitudes and Wave Energy along the Energy Dispersion Paths for Rossby Waves in the Quasigeostrophic Barotropic Model

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Advances in Atmospheric Sciences 2022年第6期39卷 876-888页

Variations in wave energy and amplitude for Rossby waves are investigated by solving the wave energy equation for the quasigeostrophic barotropic potential vorticity *** results suggest that compared with rays in the nondivergent barotropic model,rays in the divergent model can have enhanced meridional and zonal propagation,accompanied by a more dramatic variability in both wave energy and amplitude,which is caused by introducing the divergence effect of the free surface in the quasigeostrophic *** rays propagating in a region enclosed by a turning latitude and a critical latitude,the wave energy approaches the maximum value inside the region,while the amplitude approaches the maximum at the turning *** can develop when both the wave energy and amplitude *** rays propagating in a region enclosed by two turning latitudes,the wave energy approaches the minimum value at one turning latitude and the maximum value at the other latitude,while the total wavenumber approaches the maximum value inside the *** resulting amplitude increases if the total wavenumber decreases or the wave energy increases more significantly and decreases if the total wavenumber increases or the wave energy decreases more *** matched roles of the energy from the basic flow and the divergence of the group velocity contribute to the slightly oscillating wave energy,which causes a slightly oscillating amplitude as well as the slightly oscillating total wavenumber.

关键词： Rossby waves quasigeostrophic barotropic model energy dispersion wave energy amplitude

A numerical study of the effect of the marginal sea on coastal upwelling in a non-linear inertial model

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Science China Earth Sciences 2014年第11期57卷 2587-2596页

作者： chao jiping KANG YanYan LI JianPing National Marine Environmental Forecasting Center LASG Institute of Atmospheric Physics Chinese Academy of Sciences College of Earth Sciences University of Chinese Academy of Sciences

Inertia theory and the finite element method are used to investigate the effect of marginal seas on coastal upwelling. In contrast to much previous research on wind-driven upwelling, this paper does not consider localized wind effects, but focuses instead on temperature stratification, the slope of the continental shelf, and the background flow field. Finite element method, which is both faster and more robust than finite difference method in solving problems with complex boundary conditions, was developed to solve the partial differential equations that govern coastal upwelling. Our results demonstrate that the environment of the marginal sea plays an important role in coastal upwelling. First, the background flow at the outer boundary is the main driving force of upwelling. As the background flow strengthens, the overall velocity of cross-shelf flow increases and the horizontal scale of the upwelling front widens, and this is accompanied by the movement of the upwelling front further offshore. Second, temperature stratification determines the direction of cross-shelf flows, with strong stratification favoring a narrow and intense upwelling zone. Third, the slope of the continental shelf plays an important role in controlling the intensity of upwelling and the height that upwelling may reach: the steeper the slope, the lower height of the upwelling. An additional phenomenon that should be noted is upwelling separation, which occurs even without a local wind force in the nonlinear model.

关键词： coastal upwelling inertia theory Finite Element Method (FEM)

Two equilibria of the Antarctic Circumpolar Current and its associated Meridional Overturning Circulation

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Science China Earth Sciences 2012年第11期55卷 315-322页

作者： chao jiping LI YaoKun National Marine Environmental Forecasting Center Beijing 100081China First Institute of Oceanography State Oceanic AdministrationQingdao 266061China State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Graduate University of Chinese Academy of Sciences Beijing 100049China

The Antarctic Circumpolar Current (ACC) and its associated Meridional Overturning Circulation (MOC) is investigated through a nonlinear inertia theory model, which consists of two layers--an upper Ekman layer driven mainly by sea surface wind stress and a lower thermocline controlled by ideal fluid nonlinear equations which can be solved by identifying the form of the arbitrary functions. The results show that the thermocline has a two-equilibrium solution though given the same Ekman layer condition. Compared to the first equilibrium, the second one has a heavier intensity and deeper circulation, which seems more consistent with the existing data.

关键词： Antarctic Circumpolar Current Meridional Overturning Circulation inertia theory two equilibria

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A semi-analytical model for the propagation of Rossby waves in slowly varying flow

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Chinese Science Bulletin 2011年第25期56卷 2727-2731页

作者： LIU Fei chao jiping HUANG Gang FENG LiCheng Key Laboratory of Regional Climate-Environment Research for Temperate East Asia Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China International Pacific Research Center University of Hawaii at Manoa Honolulu 96822 USA National Marine Environmental Forecasting Center Beijing 100081 China State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100083 China

Instead of using complicated general circulation models (GCMs), a simple semi-analytical model based on ray theory has been used to study energy evolution and ray path of Rossby waves in slowly varying mean flows. Our model yields similar results to those calculated from barotropic models, and also provides a chance to study Rossby waves in the slowly varying flows with both vertical and meridional shears. The model results show that upward Rossby waves can only grow in westerlies, and decay when further ascend. The baroclinic Rossky waves are restrained by the β effect in lower latitude. In the westerly jet with meridional and vertical shears, the barotropic Rossby waves originated from south of the westerly jet, and these can grow while propagating upper-northward. The baroclinic Rossby waves originated from north of the westerly jet and can grow while propagating upward and southward. Such a semi-analytical model provides a simple forecasting tool to allow study of the local weather anomalies to the heating/topography forcing associated with the global warming.

关键词： Rossby波半解析模型传播模式大气环流模型变流西风急流 GCMS 射线路径

The dynamical evolution theory of the isolated oasis system

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Science China Earth Sciences 2015年第3期58卷 436-447页

作者： LI YaoKun chao jiping College of Global Change and Earth System Science Beijing Normal University National Marine Environmental Forecasting Center

Assume that an oasis and its surrounding desert consist of an isolated system without mass and energy exchange with the outer *** characteristics of oasis evolution have been explored under the condition of system energy *** results show that oasis evolves with two equilibrium *** first equilibrium suggests a stable expansive and an unstable degraded oasis whereas the second equilibrium indicates a stable shrink and an unstable increase of the oasis *** one equilibrium state is unstable,the components of the isolated system(oasis and desert) would tend to be no energy exchange and they each reach to energy balance *** would maintain its initial area in this *** analyses point out that the two equilibrium states have completely different *** the first equilibrium state,a higher vegetation albedo,lower soil albedo and larger canopy resistance,and direr soil both contribute to the oasis area expansion,accompanying an excessive large desert soil and vegetation canopy temperature difference(SCTD).In the second equilibrium state,however,a lower vegetation albedo,higher soil albedo and small canopy resistance,and wetter soil benefit the oasis area to stay near its initial value,following a moderate *** convergent trajectories of the initial values in phase space are influenced by the separatrices of the equilibrium *** temperature is an advantage factor for initial values convergent to the oasis expansion solution.

关键词： energy conservation oasis desert two equilibrium states

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The numerical simulation of Pacific Ocean circulation with five-level model

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Acta Oceanologica Sinica 1993年第3期12卷 395-404页

作者： Xing Runan and chao jiping Beijing Meteorological College, Beijing 100081 China National Research Center for Marine Environmental Forecasts, Beijing 100081, China

A five-level oceanic primitive equation model has been developed. This model is integrated numerically with annual mean wind stress and heat flux at sea surface for 30 a. The ocean circulations tend to quasi-stability. The simulated results show that the computed annual mean currents and sea surface temperature agree well with the observations.

关键词： heat The numerical simulation of Pacific Ocean circulation with five-level model

EL NINO AND CLIMATE ANOMALY IN CHINA

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Bulletin of the Chinese Academy of Sciences 1999年第1期13卷 57-61页

作者： chao jiping(The State Research Center on Marine Environment)

From the point of view of atmospheric science and oceanography, the author explores the origin of abnormal climatic phenomena of El Nino and La Nina, the interaction between the two and their influence on climatic ano... 详细信息

关键词： Nino EL NINO AND CLIMATE ANOMALY IN CHINA EI La ENSO

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热带地转适应运动的动力学基础

气象学报 2000年第1期58卷 1-10页

作者：巢纪平国家海洋环境预报研究中心北京100081

文中讨论了热带斜压大气地转适应过程中的若干动力学约束关系 ,在不考虑行星位势涡度梯度的前提下给出了三维重力惯性波的频散方程、位势涡度时间不变式。在这基础上指出由于 Taylor- Proudman定理成立 ,运动将趋于水平化。同时指出 ,... 详细信息

文中讨论了热带斜压大气地转适应过程中的若干动力学约束关系 ,在不考虑行星位势涡度梯度的前提下给出了三维重力惯性波的频散方程、位势涡度时间不变式。在这基础上指出由于 Taylor- Proudman定理成立 ,运动将趋于水平化。同时指出 ,在热带纬圈半地转平衡更易出现。地转适应后的运动 ,一般是水平无辐散的 ,虽然垂直运动趋于零 ,但物理场随高度仍然有变化 ,即是层结的。

关键词：热带斜压大气地转适应动力学约束