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THE RESPONSES OF THE THIRD GENERATION OF IAP/LASG OCEANIC GCM TO DIFFERENT EXTERNAL FORCING

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Journal of Hydrodynamics 2001年第3期13卷 107-114页

作者： Li Wei, Liu Hai long, Zhang Xue hong LASG institute of atmospheric physics,{3., Beijing 10002., china Fang Guo hong institute of Oceanology,{3., Qingdao 266071, china Key Laboratory of Marine Scienc LASG Inst. of atmospheric physics Chinese Acad. of Sci. Beijing 100029 China

Forced by different wind stress as well as different surface heat flux, three 10 year integrations using L3.T63.oceanic GCM are carried out. The annual mean state, seasonal cycle and interannual variability of the upper ocean temperature over the tropical Pacific are examined. In the case of annual mean state of sea surface temperature, relults from D15c and D15e are alike and have good agreement with NCEP data. Defects in D15d include the excessively higher SST over warm pool region and higher SST along the eastern coast. The corresponding westward displacement of cold water is also noticeable. All the experiments represent the annual cycle of SST in the eastern equatorial Pacific while the amplitudes are weaker compared to NCEP data. The intensity of interannual variability of SST in eastern equatorial Pacific is markedly improved D15d and is perfectly comparative with that from NCEP data. The eastward propagations of the interannual variability of upper ocean heat content along the equator in 1982/1983.E1 Nio are well represented in all experiments. On the onset stage of 1982/1983.E1 Nio, the modeled interannual variabilities of SST and heat content are generally the same among all experiments. It is the weakest interannual variability of surface heat flux, which damps SST variability during the mature phase of E1 Nio, that results in a most intensified SST variability in D15d.

关键词： Oceanic GCM tropical pacific SST

Using lightning locating system based on time-of-arrival technique to study three-dimensional lightning discharge processes

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Science china Earth sciences 2010年第4期53卷 591-602页

作者： ZHANG GuangShu1,WANG YanHui1,QIE XiuShu2,ZHANG Tong1,ZHAO YuXiang1,3.LI YaJun1 & CAO DongJie11 Laboratory for Climate Environment and Disasters of Western china,Cold and Arid Regions Environmental and Engineering Research institute,chinese {3. of sciences,Lanzhou 73.000,china 2 Laboratory for Middle Atmosphere and Global Environment Observation(LAGEO),institute of atmospheric physics,chinese {3. of sciences,Beijing 10002.,china 3.Department of physics,Tianshui Normal College,Tianshui 741001,china Laboratory for Climate Environment and Disasters of Western china Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou China Laboratory for Middle Atmosphere and Global Environment Observation (LAGEO) Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Department of physics Tianshui Normal College Tianshui China

A time-of-arrival(TOA) system based on GPS technology for locating VHF radiation sources from lightning has been developed and used in observation sites in the northern Shandong Province,*** 3. images of the lightning progression have been obtained successfully for the first time in *** 3.-channel evolutions of typical negative CG,positive CG and IC lightning flashes have been discussed together with the data of fast electric field *** was found that significant differences existed between the negative and positive CG lightning flashes in terms of the initiation and propagation of the radiation *** preliminary breakdown of a negative CG lightning flash propagated at a speed about 5.2×104 m/*** stepped leader of negative CG lightning flashes was trigged by negative initial ***,it propagated downward at a speed of 1.3.105 m/*** initial process of the positive CG lightning flashes was also a propagation process of negative *** streamers propagated dominantly horizontally in the positive charge region and accumulated positive charges at the origin of the lightning,and as a consequence,initiated downward positive streamers.A new type of lightning discharge that was triggered by a narrow bipolar pulse(NBP) is discussed in this *** NBP was originated at altitude of about 10.5 km in the upper positive charge *** a distinct difference from normal IC flash,its channels extended horizontally all around and produced a lot of radiation *** source power of the NBP could approach 16.7 kW,which is much greater than that of normal lightning discharge ranging between 100 mW and 500 *** 3. propagation of this new type of lightning discharge was observed and obtained for the first time in *** possible initiation mechanism of this new type of light-ning is discussed here.

关键词： time-of-arrival(TOA) technique three dimensional lightning locating system discharge process narrow bipolar pulse new-type of IC lightning

The relationship between short-range motion of atmosphere and ocean and conservative and nonconservative scheme

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Science Bulletin 2003年第10期48卷 999-1001页

作者： LIN Wantao, JI Zhongzhen & WANG Bin LASG,institute of atmospheric physics,{3., Beijing 10002., china LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

Taking one-dimensional shallow water wave equation as an example, a comparative analysis on the computational stability related to the short-range motion of atmosphere and ocean is carried out for the conservative and nonconservative scheme, and it is pointed out that the computational stability of conservative scheme is absolutely different from that of the nonconservative scheme. The relationship between the short-range motion of atmosphere and ocean and the conservative and nonconservative scheme is further discussed. The constructed conservative scheme is proved to be stable by the numerical experiment for the short-range motion of atmosphere and ocean while the CTCS scheme is unstable. So that the conservative scheme for the solution of this kind of problem has more advantages.

关键词： short-range motion of atmosphere and ocean conservative scheme nonconservative scheme computational stability.

Evolution of desertification in a two-dimensional energy balance model coupled with thermodynamics and dynamics

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Science china Earth sciences 2010年第11期53卷 1726-1733页

作者： CHAO JiPing1,2 & LI YaoKun3.4 1National Marine Environmental Forecasting Center, Beijing 100081, china 2First institute of Oceanography, State Oceanic Administration, Qingdao 266061, china 3.tate Key Laboratory of Numerical Modeling for {3. sciences and Geophysical Fluid Dynamics, institute of {3. physics, chinese academy of sciences, Beijing 10002., china 4Graduate University of chinese academy of sciences, Beijing 100049, china National Marine Environmental Forecasting Center Beijing China First institute of Oceanography State Oceanic Administration Qingdao China State Key Laboratory of Numerical 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

The relationship between desert evolution and change in albedo has been investigated quasi-analytically using a zonal mean two-dimensional energy balance model which considers the radiation transmission process due to thermodynamics and bound- ary layer movement caused by kinetics. A climate state including temperature, zonal wind, meridional wind and vertical wind can be simulated according to the current zonal distribution of albedo. Given desert distribution, characterized by the value and distribution of albedo, the response of climate on albedo has been studied to analyze the evolution of desert climate. One significant result is that the simple model can reproduce mean meridional circulation. Another result indicates that climate corresponds to two equilibria. This happens when the junction temperature between vegetation and desert is higher than a certain critical value. As for the first equilibrium, the desert belt is predicted to move southward in the northern hemisphere with the increasing values of albedo, which corresponds to the current trend of climate change. For the second equilibrium, vegetation will expand northward with increasing values of albedo, which would indicate a narrowing of the desert belt. In order to determine if the two equilibria exist, new physical models are needed.

关键词： two-dimensional energy balance model desertification two equilibria

Inorganic chemical composition and source signature of PM2.5 in Beijing during ACE-Asia period

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Science Bulletin 2003年第10期48卷 1002-1005页

作者： ZHANG Renjian, XU Yongfu & HAN Zhiwei LAPC, institute of atmospheric physics,{3., Beijing 10002., china LAPC Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

Aerosol samples for PM2.5 were collected in Beijing for 3. consecutive days from March to April 2001 using an IMPROVE Sampler. Concentrations of 20 elements in PM2.5 were determined using a PIXE method. Results show that the average mineral dust concentration of PM2.5 was 14.6 mg/m3.during the observation period. On the sand-dust event days of March 21 and April 10, dust PM2.5 mass concentrations were 62.4 and 54.1 mg/m3. respectively. These demonstrate that fine particle pollution by dust event in Beijing was very severe. The enrichment factors of S and Cu reached minimums on the dusty days and were high on the non-dusty days. It is considered that enrichment factors of elements in PM2.5, which are associated with human activities, can probably provide an effective method to distinguish local sources from external sources of dust. Factor analysis on the chemical composition in PM2.5 shows that sources of crustal matters, anthropogenic emission, and oil combustion contributed to PM2.5 levels in air in the springtime of 2001 in Beijing.

关键词： dust ACE-Asia PM2.5 chemical composition source apportionment.

A three-dimensional variational ocean data assimilation system:Scheme and preliminary results

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Science china Earth sciences 2006年第11期49卷 1212-1222页

作者： ZHU Jiang1,2, ZHOU Guangqing1, YAN Changxiang1, FU Weiwei1 & YOU Xiaobao1,3.1. International Center for Climate and Environment sciences, institute of atmospheric {3., chinese academy of sciences, Beijing 10002., china 2. Jiangsu Key Laboratory of Meteorological Disaster, Nanjing University of Information Science and Technology, Nanjing 210044, china 3. Beijing institute of Applied Meteorology, Beijing 10002., china International Center for Climate and Environment sciences Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Jiangsu Key Laboratory of Meteorological Disaster Nanjing University of Information Science and Technology Nanjing China Beijing institute of Applied Meteorology Beijing China

A new 3.VAR-based Ocean Variational Analysis System (OVALS) is developed. OVALS is capable of assimilating in situ sea water temperature and salinity observations and satellite altimetry data. As a component of OVALS, a new variational scheme is proposed to assimilate the sea surface height data. This scheme considers both the vertical correlation of background errors and the nonlinear temperature-salinity relationship which is derived from the generalization of the linear balance constraints to the nonlinear in the 3.VAR. By this scheme, the model temperature and salinity fields are directly adjusted from the altimetry data. Additionally, OVALS can assimilate the temperature and salinity profiles from the ARGO floats which have been implemented in recent years and some temperature and salinity data such as from expendable bathythermograph, moored ocean buoys, etc. A 21-year assimilation experiment is carried out by using OVALS and the Tropical Pacific circulation model. The results show that the assimilation system may effectively improve the estimations of temperature and salinity by assimilating all kinds of observations. Moreover, the root mean square errors of temperature and salinity in the upper depth less than 420 m reach 0.63. and 0.3. psu.

关键词： data assimilation, 3.VAR, sea surface height, ARGO floats.

Semi-analytical analysis of the response of the air temperature over the land surface to the global vegetation distribution

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chinese Science Bulletin 2009年第14期54卷 2499-2505页

作者： LIU Fei1,2 & CHAO JiPing3.4 1 institute of atmospheric physics,{3., Beijing 10002., china 2 Graduate University of{3., Beijing 100049, china 3.National Marine Environmental Forecasting Center, Beijing 100081, china 4 First institute of Oceanography, State Oceanic Administration of china, Qingdao 266061, china institute of atmospheric physics{3. Beijing China Graduate University of chinese academy of sciences Beijing China National Marine Environmental Forecasting Center Beijing China First institute of Oceanography State Oceanic Administration of China Qingdao China

Response of the air temperature over the land surface to the global vegetation distribution is investigated, using a three-dimensional governing equation to simulate the steady, large-scale, limited amplitude perturbation of the free, inviscid and adiabatic atmosphere. The adoption of the static equation leads to a temperature governing equation in the terrain following coordinate. With the prescribed temperature as the upper boundary condition and the radiation balance as the lower boundary condition, the semi-analytical solution of the global circulation temperature can be calculated. In this article, only the air temperature (at 2 m height) over the land surface is analyzed, and the result suggests that this model can simulate the air temperature pattern over the land surface reasonably. A better simulation occurs when a simple feedback of the albedo on the temperature is included. Two sensitivity experiments are analyzed through this model. One suggests that the air temperature over the land surface descends obviously when the land surface is covered with ice all over, while another suggests that the air temperature rises a little when the land surface is covered with forest except the ice-covered area. This model appears to be a good tool to study the response of the air temperature to the vegetation distribution. Limitations of the model are also discussed.

关键词：空气温度植被分布陆地表面反应解析分析模拟模式控制方程边界条件

Optimality of a nonlinear stability criterion of two-layer Phillips model

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chinese Science Bulletin 1998年第8期43卷 656-659页

作者： MU Mu State Key Laboratory of Numerical Modelling for atmospheric sciences and Geophysical Fluid Dynamics, institute of atmospheric physics, chinese academy of sciences, Beijing 10002., china State Key Laboratory of Numerical Modelling for atmospheric sciences and Geophysical Fluid Dynamics. institute of atmospheric physics Chinese Academy of Sciences Beijing China

The optimality of a nonlinear stability criterion of motions of two_layer Phillips model is investigated. The result shows that for a given zonal periodical channel, there exist cases that there is no normal mode which grows exponentially even if the sufficient conditions of the criterion are destroyed. On the other hand, the above criterion is optimal in the following sense: when the sufficient conditions of the criterion are destroyed, except some critical cases, there exists a finite zonal periodical channel, in which there is a zonal normal mode growing exponentially.

关键词： Phillips model nonlinearity stability.

Arabian Peninsula-North Pacific Oscillation and its association with the Asian summer monsoon

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Science china Earth sciences 2008年第7期51卷 1001-1012页

作者： SUN JianQi1, YUAN Wei2 & GAO YuZhong3.1 Nansen-Zhu International Research Centre, institute of atmospheric physics,{3., Beijing 10002., china 2 china Meteorological Administration Training Centre, Beijing 100081, china 3.Heilongjiang Meteorological Observatory, Harbin 15003., china Nansen-Zhu International Research Centre Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China china Meteorological Administration Training Centre Beijing China Heilongjiang Meteorological Observatory Harbin China

Using correlation and EOF analyses on sea level pressure from 57-year NCEP-NCAR reanalysis data, the Arabian Peninsula-North Pacific Oscillation (APNPO) is identified. The APNPO reflects the co-variability between the North Pacific high and South Asian summer monsoon low. This teleconnec- tion pattern is closely related to the Asian summer monsoon. On interannual timescale, it co-varies with both the East Asian summer monsoon (EASM) and South Asian summer monsoon (SASM); on decadal timescale, it co-varies with the EASM: both exhibit two abrupt climate changes in the middle 1960s and the late 1970s respectively. The possible physical process for the connections between the APNPO and Asian summer monsoon is then explored by analyzing the APNPO-related atmospheric circulations. The results show that with a strong APNPO, the Somali Jet, SASM flow, EASM flow, and South Asian high are all enhanced, and an anomalous anticyclone is produced at the upper level over northeast china via a zonal wave train. Meanwhile, the moisture transportation to the Asian monsoon regions is also strengthened in a strong APNPO year, leading to a strong moisture convergence over India and northern china. All these changes of circulations and moisture conditions finally result in an anoma- lous Asian summer monsoon and monsoon rainfall over India and northern china. In addition, the APNPO has a good persistence from spring to summer. The spring APNPO is also significantly corre- lated with Asian summer monsoon variability. The spring APNPO might therefore provide valuable in- formation for the prediction of Asian summer monsoon.

关键词： Arabian Peninsula-North Pacific Oscillation East Asian summer monsoon South Asian summer monsoon wave train abrupt climate change