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Development of an Integrated Vertical-Slantwise Convective Parameterization Scheme and Its Associated Numerical Experiments

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Acta meteorologica Sinica 2011年第4期25卷 405-418页

作者：费建芳伍荣生黄小刚王元程小平 institute of meteorology PLA University of Science & Technology institute of atmospheric sciences Nanjing University

An integrated vertical-slantwise convective parameterization scheme, based on the vertical Kuo-Anthes and the slantwise Nordeng convective parameterization schemes, is introduced into the MM5 model. By employing the MM5 model with the proposed scheme, numerical simulations of a snowstorm event that occurred over southern China on 28-29 January 2008 and of Typhoon Haitang （2005） are conducted. The results indicate that during the snowstorm event, the atmosphere was convectively stable in the vertical direction but with conditional symmetric instability （CSI） in the lower troposphere, and when the area of CSI developed and extended to upper levels, strong rising motion occurred and triggered the release of large amount of energy, producing enhanced convective precipitation with the total precipitation much closer to the observation. The development and strengthening of CSI corresponded to changes in the intensity of snowfall, convergence, and ascending motions of air, revealing that CSI was responsible for the initiation and growth of the snowstorm. The results from a 72-h explicit simulation of Typhoon Haitang indicate that CSI occurred mainly at lower levels with a well-defined spiral structure, and it tended to have a larger impact on the intensity of typhoon than on its track. The minimum pressure at the typhoon center for the 72-h runs with the integrated vertical-slantwise convective parameterization scheme was on average 3 hPa （maximum 8 hPa） lower than that from the runs with only the vertical cumulus parameterization scheme. Introducing the influence of CSI into the model has improved the warm core structure at the middle and upper levels of the typhoon, with stronger and persistent upward motions causing increased precipitation, and the latent heat released through convection in turn made the typhoon develop further.

关键词： snowstorm typhoon conditional symmetric instability (CSI) the integrated vertical-slantwise convective parameterization scheme numerical simulation

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Ocean internal waves interpreted as oscillation travelling waves in consideration of ocean dissipation

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Chinese Physics B 2014年第5期23卷 52-59页

作者：姜祝辉黄思训游小宝肖义国 College of meteorology and Oceangraphy PLA University of Science and Technology Beijing institute of Applied meteorology institute of atmospheric Physics Chinese Academy of Sciences

Most studies of the synthetic aperture radar remote sensing of ocean internal waves are based on the solitary wave solutions of the Korteweg-de Vries （KdV） equation, and the dissipative term in the KdV equation is not taken into account. However, the dissipative term is very important, both in the synthetic aperture radar images and in ocean models. In this paper, the traveling-wave structure to characterize the ocean internal wave phenomenon is modeled, the results of numerical experiments are advanced, and a theoretical hypothesis of the traveling wave to retrieve the ocean internal wave parameters in the synthetic aperture radar images is introduced.

关键词： synthetic aperture radar ocean internal waves oscillation travelling wave Korteweg-de Vriesequation

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Space-time objective decomposition of vortex equations and mechanism analysis of subtropical high abnormal activities

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Applied Mathematics and Mechanics(English Edition) 2009年第10期30卷 1263-1270页

作者：洪梅张韧薛峰刘科峰 institute of meteorology PLA University of Science and Technology institute of atmospheric Physics Chinese Academy of SciencesLASG institute of meteorology PLA University of Science and Technology institute of atmospheric Physics Chinese Academy of SciencesLASG

To analyze the dynamic mechanism of unusual activities of the subtropical high, the space-time varible separation of the partial differential vortex equations is carried out with Galerkin methods based on the heat force and the whirl movement dissipation effect. Aiming at the subjective and man-made conventional method of choice in the space basis functions, we propose to combine the empirical orthogonal function （EOF） analysis with the genetic algorithm to inverse the space basis functions from the actual sequence of fields. A group of trigonometric functions are chosen as a generalized space basis function. With the least-squares error of the basis function and EOF typical fields, and with the complete orthogonality of basis functions, we can get the dual-bound function. A genetic algorithm is then introduced to carry out surface fitting and coefficient optimization of the basis function. As a result, the objective and reasonable constant differential equation of the subtropical high is obtained by inversion. Finally, based on the obtained nonlinear dynamics model, the dynamic behavior and mechanism of the subtropical high is analyzed and discussed under the influence of heat force. We find that solar radiation and zonal differences in land and sea are important factors impacting the potential field and flow field changes of the subtropical areas. These factors lead to strength changes of the subtropical high and medium-term advance/retreat activities. The former is a gradual change, while the latter shows more break characteristics. Meaningful results are obtained in the analysis.

关键词： basis function fitting empirical orthogonal function (EOF) genetic algorithm nonlinear equation of vortex subtropical high

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A Condensed Gas-Phase Chemical Model and Its Application

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Advances in atmospheric sciences 1999年第4期16卷 608-618页

作者：王体健孙照渤李宗恺 Department of atmospheric sciences Nanjing University Nanjing Nanjing institute of meteorology Nanjing

Using the 'lumped mechanism' and 'counting species' methods, we developed a condensed gas-phase chemical model based on a simplified one. The modified quasi-steady-state approximation (QSSA) scheme and the error redistribution mass conservation technique are adopted to solve the atmospheric chemistry kinetic equations. Results show that the condensed model can well simulate concentration variations of gas species such as SO2, NOX, O-3, H2O2 and conversion rates of SO2 and NOX transformation to H2SO4 and HNO3. These results are in good agreement with those from the simplified model. The conversion rates of SO2 and NOX under different initial concentrations and meteorological conditions are computed, and the results can be directly applied to regional acid deposition model.

关键词： gas-phase chemistry conversion rate

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Annual precipitation fields secular variation over global land areas for 1948—2000

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Chinese Science Bulletin 2003年第3期48卷 281-286页

作者： SHI Neng & CHEN Luweng Department of atmospheric sciences, Nanjing institute of meteorology, Nanjing 210044, China Department of atmospheric sciences Nanjing Institute of Meteorology Nanjing China

The secular variation over the global land an-nual precipitation (GLAP) fields for 1948—2000 is investi-gated. Evidence suggests that the GLAP abruptly reduced around 1978 and experienced a decrease of 0.54 mm/a, on average. Fuzzy clustering is used to group the annual pre-cipitation over commonly-used 36 latitudes belts into six belts for examining its secular variation. The results show that, except northern high-latitudes (60°—90°N) where it is slightly increased, the precipitation is decreased, especially in 35°N—35°S, and the diminution is the maximum of 0.98 mm/a at tropics. Moreover, identification of 1948—2000 flood/drought years on a global basis is made, showing no-ticeable interdecadal variations. During the years of warm (cold) events the precipitation decreases (increases) by 15.4 mm (14.4 mm) per year, on average. It can be assumed that global warming and frequent ENSO occurrences from the end of the 1970s maybe serve as the root cause of the dimi-nution.

关键词：全球降水长期变化年降水 ENSO 陆地 1948-2000年

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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 Laboratory of atmospheric 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

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Model Analysis of Influences of Aerosol Mixing State upon Its Optical Properties in East Asia

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Advances in atmospheric sciences 2013年第4期30卷 1201-1212页

作者：韩霄张美根朱凌云许丽人 State Key Laboratory of atmospheric Boundary Layer Physics and atmospheric Chemistry Institute of Atmospheric Physics Chinese Academy of Sciences Shanxi Province institute of Meteorological sciences Beijing institute of Applied meteorology

The air quality model system RAMS （Regional atmospheric Modeling System）-CMAQ （Models-3 Com- munity Multi-scale Air Quality） coupled with an aerosol optical/radiative module was applied to investigate the impact of different aerosol mixing states （i.e., externally mixed, half externally and half internally mixed, and internally mixed） oil radiative forcing in East Asia. The simulation results show that the aerosol optical depth （AOD） generally increased when the aerosol mixing state changed from externally mixed to internally mixed, while the single scattering albedo （SSA） decreased. Therefore, the scattering and absorption proper- ties of aerosols can be significantly affected by the change of aerosol mixing states. Comparison of simulated and observed SSAs at five AERONET （Aerosol Robotic Network） sites suggests that SSA could be better estimated by considering aerosol particles to be internally mixed. Model analysis indicates that the impact of aerosol mixing state upon aerosol direct radiative forcing （DRF） is complex. Generally, the cooling effect of aerosols over East Asia are enhanced in the northern part of East Asia （Northern China, Korean peninsula, and the surrounding area of Japan） and are reduced in the southern part of East. Asia （Sichuan Basin and Southeast China） by internal mixing process, and the variation range can reach ＋5 W m 2. The analysis shows that the internal mixing between inorganic salt and dust is likely the main reason that the cooling effect strengthens. Conversely, the internal nfixture of anthropogenic aerosols, including sulfate, nitrate, ammonium, black carbon, and organic carbon, could obviously weaken the cooling effect.

关键词： aerosol optical properties internal mixing state direct radiative forcing CMAQ

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Study on a Boundary-layer Numerical Model with Inclusion of Heterogeneous Multi-layer Vegetation

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Advances in atmospheric sciences 1999年第3期16卷 431-442页

作者：曾新民赵鸣苏炳凯王汉杰 Department of atmospheric sciences Nanjing University Nanjing The Air Force institute of meteorology Nanjing

On the basis of improving the algorithm of the mixing length in and above forest canopies, a PBL numerical model including the multi-layer, heterogeneous vegetation is developed. Simulations indicate thatdifferent treatments of mixing length can make a great difference in the wind field especially for dense *** results *** the improved mixing length scheme are in better agreement with observations than thosefrom the original scheme. It may be expected that the improved mixing length scheme can lead to more rational turbulent transfer than the original one. From the sensitivity experiments, we obtain the characteristics of both wind and temperature profiles in and above plant canopies, e.g., during the daytime, a stablethermal stratitication exists near the surface in the canopies, but a neutral or slightly unstable condition appears above plant canopies. while at night the reverse situations occur; the increase of the temperature of thedense-forest case is less than that of the sparse-forest case, the windspeed is reduced within the canopy layer and the large wind shear occurs near the treetop, etc.

关键词： Numerical model Boundary layer turbulence Vegetation Mixing length

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Tropical Convective Activities Related to Summer Rainfall Anomaly in China

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Advances in atmospheric sciences 2000年第1期17卷 121-128页

作者：郭品文田红刘宣飞 Department of atmospheric sciences Nanjing Institute of Meteorology Nanjing Anhui Meteorological Center Hefei

The paper presents the SVD-revealed relation of the tropical convection anomaly patterns to the summer rainfall counterparts of China, indicating that a) the ENSO-associated tropical con-vection anomaly is highly advantageous but the corresponding rainfall anomaly can only account for 10.3% of total variance, the rainfall anomaly related to tropical monsoon variation with the northern South China Sea as the center of convection abnormality for 18.8% and to the variation inside the tropical monsoon for 11.2%; b) the ENSO-related summer precipitation anomaly dis-plays a pattern of excessive rainfall in the south and deficit in the north, the anomaly relative to the tropical monsoon variation a pattern of more precipitation in the Yangtze River valleys and less in North, Northeast and South China, and that in relation to the variation within the tropical mon-soon a pattern of two rainbands, one in the Yangtze River valleys and the other in North China. Key words Tropical convection - Singular value decomposition (SVD) - Rainfall pattern (1)This work is supported by the National Natural sciences Foundation of China under Grant No. 49775265.

关键词： Tropical convection Singular value decomposition (SVD) Rainfall pattern

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Structures and Characteristics of the Windy atmospheric Boundary Layer in the South China Sea Region during Cold Surges

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Advances in atmospheric sciences 2015年第6期32卷 772-782页

作者： CHENG Xue-Ling HUANG Jian WU Lin ZENG Qing-Cun State Key Laboratory of atmospheric Boundary Layer Physics and atmospheric Chemistry Institute of Atmospheric Physics Chinese Academy of Sciences institute of Tropical and Marine meteorology China Meteorological Administration institute of atmospheric Physics Chinese Academy of Sciences

An observational analysis of the structures and characteristics of a windy atmospheric boundary layer during a cold air outbreak in the South China Sea region is reported in this paper. It is found that the main structures and characteristics are the same as during strong wind episodes with cold air outbreaks on land. The high frequency turbulent fluctuations （period 〈 1 min） are nearly random and isotropic with weak coherency, but the gusty wind disturbances （1 rain〈period 〈 10 min） are anisotropic with rather strong coherency. However, in the windy atmospheric boundary layer at sea, compared with that over land, there are some pronounced differences：（1） the average horizontal speed is almost independent of height, and the vertical velocity is positive in the lower marine atmospheric boundary layer; （2） the vertical flux of horizontal momentum is nearly independent of height in the low layer indicating the existence of a constant flux layer, unlike during strong wind over the land surface; （3） the kinetic energy and friction velocity of turbulent fluctuations are larger than those of gusty disturbances; （4） due to the independence of horizontal speed to height, the horizontal speed itself （not its vertical gradient used over the land surface） can be used as the key parameter to parameterize the turbulent and gusty characteristics with high accuracy.

关键词： turbulence wind gust coherent structure cold surge windy marine atmospheric boundary layer

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