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Oscillatory Rossby Solitary Waves in the Atmosphere

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Advances in Atmospheric Sciences 1994年第1期11卷 65-73页

作者：陈忠明刘富明李小平陶杰 Chengdu institute of Plateau meteorology Chengdu Nanjing institute of meteorology Nanjing

The linear Rossby wave frequency expression is expanded at higher accuracy based on the scale difference characteristics of atmospheric long waves in the x and y directions. That the nature of the waves represented by the expansion is identical to that of the original ones is demonstrated both in phase velocity C and wave energy dispersion speed C., followed by the derivation of the nonlinear expression describing atmospheric long wave behaviors with the associated approximate analytic solution obtained. Then, for the first time atmospheric' oscillatory Rossby solitary wave with its dispersion relation is obtained by numerical calculation with the aid of physical parameters of the real atmosphere. The solitary wave is found to be very close to such longwave systems as blocking highs and cut-off depressions in the actual atmosphere.

关键词： Longwave approximation Oscillatory Rossby solitary wave

Nonlinear interaction of axisymmetric circulation and nonaxisymmetric disturbances in hurricanes

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Science China Earth Sciences 2004年第1期47卷 58-67页

作者： LUO Zhexian Nanjing institute of meteorology Nanjing 210044 China

The nonlinear interaction of axisymmetric circulation and nonaxisymmetric disturbances in hurricanes is numerically studied with a quasigeostrophic barotropic model of a higher resolution. It is pointed out that the interaction may be divided into two categories. In the first category, nonaxisymmetric disturbances decay, the coordinate locus of maximum relative vorticity ζmax is seemingly unordered, and the central pressure of hurricane rises; while in the second one, nonaxisymmetric disturbances develop, the locus of ζmax shows an ordered limit cycle pattern, and the central pressure falls remarkably. A succinct criterion is given to judge which category the interaction belongs to, i.e. the vortex beta Rossby number at the initial time Rβ 1 to the developing one. Finally, practical applications of theoretical results of the rotational adaptation process presented by Zeng and numerical results in this paper to the hurricane intensity prediction in China are also discussed.

关键词： rotational adaptation process, hurricane, axisymmetric circulation, nonaxisymmeteric disturbance, hurricane prediction.

ANALYSIS OF TROPICAL CYCLONE PRECIPITATION FOR DIFFERENT INTENSITY CLASS IN NORTHWEST PACIFIC WITH TRMM DATA

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Journal of Tropical meteorology 2016年第2期22卷 118-126页

作者：刘喆白洁黄兵严军周华张文军 institute of Aeronautical meteorology Beijing

Combined with TRMM products and Tropical Cyclone(TC) best track data in Northwest Pacific from 1 January 2003 to 31 December 2009,a total of 118 TCs,including 336 instantaneous TC precipitation observations are established as the TRMM TC database,and the database is stratified into four intensity classes according to the standard of TC intensity adopted by China Meteorological Administration(CMA):Severe Tropical Storm(STS),Typhoon(TY),Severe Typhoon(STY) and Super Typhoon(SuperT Y).For each TC snapshot,the mean rainfall distribution is computed using 10-km annuli from the TC center to a 300-km radius,then the axisymmetric component of TC rainfall is represented by the radial distribution of the azimuthal mean rain rate;the mean rain rates,rain types occurrence and contribution proportion are computed for each TC intensity class;and the mean quadrantal distribution of rain rates along TCs motion is *** result shows that:(1) TCs mean rain rates increase with their intensity classes,and their radial distributions show single-peak characteristic gradually,and furthermore,the characteristics of rain rates occurrence and contribution proportion change from dual-peak to single-peak distribution,with the peak rain rate at about 5.0mm/h;(2) Stratiform rain dominate the rain type in the analysis zone,while convective rain mainly occurred in the eye-wall region;(3) The values of mean rain rate in each quadrant along TCs motion are close to each other,relatively,the value in the right-rear quadrant is the smallest one.

关键词： TRMM tropical cyclone intensity class precipitation

A Grid-nested, Water-bearing, N-Level Primitive Equation Model

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Chinese Science Bulletin 1993年第17期38卷 1464-1469页

作者：郑良杰夏大庆 Beijing institute of Applied meteorology

In order to forecast and research the characteristics of cloud physics in large-scale systems, we have developed a grid-nested, water-bearing, N-level primitive equation model. The conventional large-scale numerical model is run in the coarse-grid region, and the water-bearing model may be run in the fine-grid region. The values on boundary grids

关键词： model primitive equation cloud physics.

Elevation Influence on Rainfall and a Parameterization Algorithm in the Beijing Area

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Journal of Meteorological Research 2019年第6期33卷 1143-1156页

作者： Linye SONG Mingxuan CHEN Feng GAO Conglan CHENG Min CHEN Lu YANG Yong WANG institute of Urban meteorology China Meteorological AdministrationBeijing 100089China Central institute for meteorology and Geodynamics Vienna A-1190Austria

Using a high-density automatic weather stations(AWS)dataset of hourly rainfall observations,the present study investigates the relationship between rainfall and elevation in the Beijing area,and further proposes a rainfall amount dependent parameterized algorithm considering the elevation effect on rainfall on hourly *** parameterization equation is defined as a segmented nonlinear model,which calculates the mountain rainfall as a function of valley rainfall *** show that there exists an evident enhancement of rainfall amount by elevation effect in the Beijing *** particular,larger rainfall amount is generally found in higher mountains,especially for slight rain and moderate ***,six representative station pairs located in valleys and on mountains respectively are selected to estimate the values of optimal parameters in the parameterization *** parameterization algorithm of elevation dependence can produce a reduction in the root-mean-square error and obtain a much closer mountain rainfall total to the observations compared with those using no elevation ***,the spatial distribution of rainfall is more realistic and accurate in mountainous terrain when elevation dependence is *** study helps to understand the variability of rainfall with complex terrain in the Beijing area,and gives a possible way to parameterize rainfall–elevation relationship on hourly timescale.

关键词： rainfall elevation influence parameterization algorithm Beijing

Spatial / Temporal Features of Antarctic Climate Change

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Advances in Atmospheric Sciences 1996年第3期13卷 375-382页

作者：葛玲梁佳兴陈毅良 Department of meteorology Nanjing Institute of MeteorologyNanjing 210044

Bused on January 1962-October 1993 mean value series of monthly mean temperature anomalies of 16 Antarctic stations on 10 standard isobanc surfaces from the surface to the 30 hPa,long term trends and periodic features of climate changes from the troposphere to the lower stratosphere over the Antarctic region are investigated by maximum entropy power spectrum analysis,and the relation between climate change of the stratosphere (troposphere) and tolal ozone (southern 500 hPa circulation) is discussed.

关键词： Antarctic Climate change: Long term trend, Periodicity Total ozone

Statistically Extrapolated Nowcasting of Summertime Precipitation over the Eastern Alps

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Advances in Atmospheric Sciences 2017年第7期34卷 925-938页

作者： Min CHEN Benedikt BICA Lukas TCHLER Alexander KANN Yong WANG institute of Urban meteorology China Meteorological Administration Beijing 100089 China Central institute for meteorology and Geodynamics Vienna 1190 Austria

This paper presents a new multiple linear regression（MLR） approach to updating the hourly, extrapolated precipitation forecasts generated by the INCA（Integrated Nowcasting through Comprehensive Analysis） system for the Eastern *** generalized form of the model approximates the updated precipitation forecast as a linear response to combinations of predictors selected through a backward elimination algorithm from a pool of predictors. The predictors comprise the raw output of the extrapolated precipitation forecast, the latest radar observations, the convective analysis, and the precipitation analysis. For every MLR model, bias and distribution correction procedures are designed to further correct the systematic regression errors. Applications of the MLR models to a verification dataset containing two months of qualified samples,and to one-month gridded data, are performed and evaluated. Generally, MLR yields slight, but definite, improvements in the intensity accuracy of forecasts during the late evening to morning period, and significantly improves the forecasts for large thresholds. The structure-amplitude-location scores, used to evaluate the performance of the MLR approach,based on its simulation of morphological features, indicate that MLR typically reduces the overestimation of amplitudes and generates similar horizontal structures in precipitation patterns and slightly degraded location forecasts, when compared with the extrapolated nowcasting.

关键词： Precipitation forecast convective Eastern correction verification backward qualified degraded morning

Construction of Vertical Wind Profile from Satellite-Derived Winds for Objective Analysis of Wind Field

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Advances in Atmospheric Sciences 1992年第2期9卷 237-246页

作者： P.N.Mahajan D.R.Talwalkar S.Nair S.Rajamani Indian institute of Tropical meteorology Pune-411008Indian Institute of Tropical Meteorology Pune-411008Indian Institute of Tropical Meteorology Pune-411008Indian Institute of Tropical Meteorology Pune-411008

During summer Monex-79, a variety of observing systems viz. research ships, research aircrafts, constant pressure balloons and geostationary satellite etc. were deployed, besides the regular conventional observations. The purpose of these additional systems was to make the best possible data for the studies on various aspects of monsoon circulation. The present study is aimed at the construction of vertical wind profile using cloud motion vectors obtained from GOES (I-O) satellite and to examine whether the constructed wind profiles improves the representation of the monsoon system, flow pattern etc. in the objective analysis. For this purpose, climatological normals of the wind field are considered as the initial guess and the objective analyses of the wind field are made with, first using only data from conventional observations over land areas, subsequently including the constructed winds from cloud motion vectors. These analyses are then compared with the standard analyses of wind field obtained from Quick Look Atlas by T. N. Krishnamurti et al. (1979).It is inferred that satellite estimated mean wind profiles show good agreement with the mean wind profiles of the research ships with RMS errors less than 5 mps below 500 hPa and less than 8 mps above 500 hPa. It is further inferred that the inclusion of constructed winds shows a positive impact on the objective analysis and improvement is seen to be more marked in the data-sparse region of the Arabian sea. Analyses which include the constructed winds show better agreement with the standard analysis, than the analyses obtained using only conventional winds. Thus, results of our study suggest that the wind profiles constructed using cloud motion vectors are of potential use in objective analysis to depict the major circulation features over the Indian region.

关键词： Construction of Vertical Wind Profile from Satellite-Derived Winds for Objective Analysis of Wind Field Wind

ON THE SOLUTION OF THE MODEL OF TWO CO-AFFECTED SPECIES

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Applied Mathematics and Mechanics(English Edition) 1994年第2期15卷 135-146页

作者：张为付吕荣庆 The Air Force institute of meteorology Nanjing

A model of two co-affected species with diffusion system in the population dynamics was discussed, where the birth functions had the characteristic index decline. Then, two kinds of parameters were introduced. One was circumstance factors αi which were connected with natural resources and the other was birth parameters βi which could be controlled. By constructing the upper-lower solutions, the existence, uniqueness and the local stability of equilibrium solution of the model were proved. It is shown that the birth parameter βi determine the developing tendency when other parameters are comparatively stable.

关键词： Differential equations Nonlinear equations