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1.
The trace gases （O3, HCl, CH4, H2O, NO, NO2） in the stratosphere play an important role, not only in the photochemical processes in which the ozone layer destroyed, but also in the radiative processes. In this paper, we review the works on the distribution and variation of the trace gases in the stratosphere and their impact on climate, which have been carried out at the University of Science and Technology of China in the recent 20 years. The Halogen Occultation Experiment （HALOE） data were used to analyse the distribution and variation of the mixing ratio of these trace gases and the temperature trends in the stratosphere in the most recent decade. And the reanalyzed National Centers of Environmental Prediction （NCEP）/NCAR data were also used to give the temperature trends and compared with the results from HALOE data. Numerical simulations were also carried out to study the impact of ozone depletion on the global climate. In this review, the distributions of the trace gases, especially those over the Qinghai-Xizang Plateau, are discussed, and the variations and trends for the trace gases in various levels in the stratosphere have been given for the most recent decade. The temperature variation and the cooling trend obtained from HALOE data in the middle and lower stratosphere for the last 13 years are significant, which agree well with the results from NCEP/NCAR data. While the temperature trend in the upper stratosphere in this period do not seem to have much cooling. The numerical simulations show that either the Antarctic ozone hole or the ozone valley over Qinghai-Xizang Plateau affect not only the temperature and circulation in the stratosphere, but also the temperature, pressure and wind fields in the troposphere, then lead to the global climate change. 相似文献
2.
In this paper, we use a spectral model for the medium-range numerical weather forecast to discuss the impact of the diurnal variation of solar radiation on the medium-range weather processes. Under the tests of two typical winter and summer cases, we find that the influences of the diurnal variation of solar radiation on summer weather are really important, especially on its rainfall, surface heat transport and 500 hPa height field. On winter weather, however, the influences are very weak. 相似文献
3.
《中国气象科学研究院年报》2001,(1)
The Study of the Continent Atmospheric Baseline (SCAB) is one of Fundamental Research Projects of the PRC Ministry of Science and Technology. It was formally started at the beginning of 2000. Scientists from the Chinese Academy of Meteorological Sciences, Mt. Wa Liguan GAW/ WMO baseline observatory (Qinghai Province), atmospheric background stations in Lin'an (Zhejiang Province), Shangdianzi (Beijing) and Longfengshan (Heilongjiang Province) participated in the project. The main stipulated tasks are fulfilled, and the final summery report is being prepared. The main advances and achievements in the SCAB are as follows: 相似文献
4.
The Antarctic ozone hole which was discovered in the mid 1980s has caused much attention from the scientists and politicians throughout the world.For the formation of the Antarctic ozone hole, most scientists believe that the man-made chemical materials such as CFCs etc. are main cause. On the other hand, the electrochemistry-dynamics theory presented by Wei (Guang Ming Daily Dec. 11 ,1990) two years ago has also caused some attention.In the paper the data of ozone, solar activity meteorology over Antarctica have been used for statistical analytical studies. Our results present some new evidence to support Wei's theory. However the influence of the human activities can never be slighted. 相似文献
5.
1.IntroductionEINifioisthemostoutstandinginterannualvariabilityintheocean.Itiswellknownthattheheatsourcedrivingtheatmosphericgeneralcirculationismainlywithinthetropics.EINinooccursinthetropicalPacificandthewarmingoftheoceanduringtheEINinocancoveralar... 相似文献
6.
Numerical Study on the Impacts of Heterogeneous Reactions on Ozone Formation in the Beijing Urban Area 总被引：2，自引：0，他引：2
The air quality model CMAQ-MADRID （Community Multiscale Air Quality-Model of Aerosol Dynamics, Reaction, Ionization and Dissolution） was employed to simulate summer O3 formation in Beijing China, in order to explore the impacts of four heterogeneous reactions on O3 formation in an urban area. The results showed that the impacts were obvious and exhibited the characteristics of a typical response of a VOC-limited regime in the urban area. For the four heterogeneous reactions considered, the NO2 and HO2 heterogeneous reactions have the most severe impacts on O3 formation. During the O3 formation period, the NO2 heterogeneous reaction increased new radical creation by 30%, raising the atmospheric activity as more NO→NO2 conversion occurred, thus causing the O3 to rise. The increase of O3 peak concentration reached a maximum value of 67 ppb in the urban area. In the morning hours, high NO titration reduced the effect of the photolysis of HONO, which was produced heterogeneously at night in the surface layer. The NO2 heterogeneous reaction in the daytime is likely one of the major reasons causing the O3 increase in the Beijing urban area. The HO2 heterogeneous reaction accelerated radical termination, resulting in a decrease of the radical concentration by 44% at the most. O3 peak concentration decreased by a maximum amount of 24 ppb in the urban area. The simulation results were improved when the heterogeneous reactions were included, with the O3 and HONO model results close to the observations. 相似文献
7.
8.
Impacts of the Kuwait Oil Fires on the Mount Qomolangma Region 总被引：6，自引：0，他引：6
Mt. Qomolangma (also known as Mt. Everest), the world’s highest mountain, is situated over the world’s highest plateau, the Tibetan Plateau. Because of its height and because of its distance from industrialized areas, the environmental state of the Mt. Qomolangma region can normally be considered “undisturbed”. It is interesting to investigate how this “undisturbed” state has been changing with time and whether it has been influenced by large environmentally disruptive events such as the Kuwait oil fires of 1990 and 1991 (Small, 1991). In order to do this, riv-er water samples were collected from the Rongpu River at Rongpu Temple Station in the summers of 1992 and 1993, as was done in 1975, and aerosol samples were collected in the summer of 1992 at the same station as was done in 1980. River water samples were analyzed using atomic absorption spectroscopy (AAS) at the Chinese Academy of Sciences. Aerosol samples were analyzed using proton-induced x-ray emission (PIXE) at the University of Fudan in Shanghai. The results show that the concentrations of chemical species in the river water at Rongpu Temple Station were much higher in the summer of 1992 than they were in 1975 and 1993, and the concentrations of atmospheric chemical species were much higher in 1992 than they were in 1980. The environment of the north slope of Mt. Qomolangma was therefore heavily polluted before and/or during the summer of 1992, possibly due to the Kuwait oil fires in 1990 and 1991. 相似文献
9.
In order to study the characteristics of cold frontal motion over the arbitrary topography, the velocity of cold frontal movement is derived by using the one layer shallow-water model. The results show that there exist the retardation in upwind side and rapid descent in the lee slope when the cold front crosses the topography. 相似文献
10.
Numerical Assessing Experiments on the Individual Component Impact of the Meteorological Observation Network on the ＂July 2000＂ Torrential Rain in Beijing 
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下载免费PDF全文 ZHANG Chaolin CHEN Min KUO Ying-Hw FAN Shuiyong ZHONG Jiqin 《Acta Meteorologica Sinica》2006,20(4):389-401
In an effort to assess the impact of the individual component of meteorological observations (ground-based GPS precipitable water vapor,automatic and conventional meteorological observations) on the torrential rain event in 4-5 July 2000 in Beijing (with the 24-h accumulated precipitation reaching 240 mm),24-h observation system experiments are conducted numerically by using the MM5/WRF 3DVAR system and the nonhydrostatic MM5 model.Results indicate that,because the non-conventional GPS observations are directly assimilated into the initial analyses by 3DVAR system,better initial fields and 24-h simulation for the severe precipitation event are achieved than those under the MM5/Litter_R objective analysis scheme. Further analysis also shows that the individual component of meteorological observation network plays their special positive role in the improvement of initial field analysis and forecasting skills.3DVAR scheme with or without radiosonde and pilot observation has the most significant influence on numerical simulation,and automatic and conventional surface meteorological observations rank second.After acquiring the supplement information from the other meteorological observations,the ground-based GPS precipitable water vapor data can more obviously reflect initial field assimilation and precipitation forecast.By incorporating the ground- based GPS precipitable water vapor data into the 3DVAR analyses at the initial time,the threat scores (TS) with thresholds of 1,5,10,and 20 mm are increased by 1%-8% for 6- and 24-h accumulated precipitation observations,respectively.This work gives one helpful example that assesses the impact of individual component of the existing meteorological observation network on the high influence weather event using 3DVAR numerical system. 相似文献
11.
《中国气象科学研究院年报》1994,(1)
ＴＨＥＥＦＦＥＣＴＯＦＴＨＥＳＬＩＧＨＴＬＹＩＮＣＬＩＮＥＤＴＥＲＲＡＩＮＯＮＴＨＥＷＩＮＤＳＨＥＡＲＮＥＡＲＴＨＥＳＵＲＦＡＣＥＺｈａｎｇＹｏｎｇｐｉｎｇ（张永萍），ＬｉＸｉｎｇｓｈｅｎｇ（李兴生），ＺｈｏｕＸｉｕｊｉ（周秀骥）ａｎｄＢｉａｎＬｉｎ... 相似文献
12.
The ability of AGCM to simulate the tropical intraseasonal oscillation (ISO) has been studied using the output of global spectral model (ALGCM (R42L9)) of the Institute of Atmospheric Physics, Chinese Academy of Sciences, and the outoput is compared with the results from NCEP/NCAR reanalysis for the year 1978-1989. The model displays an evident periodic signal of the tropical ISO. Basic propagating characters of the tropical ISO are captured, and changes in phase speed between Eastern and Western Hemispheres are also well presented, and the simulation of eastward propagation is better than that of westward propagation. This model has increased the ability to simulate the strength of the tropical ISO, especially at 200 hPa, and basically simulates the horizontal structure of wind characterized by the convergence in low-level and divergence in upper-level. The vertical structure of the zonal wind is also well reproduced. Moreover, observed results show that the representing of seasonal preference to form strong ISO in winter and spring is related to ISO's interannual variability, but it is shown in this model with strong ISO in winter and summer and weak ISO in spring and autumn. Structures of some physical elements such as vertical velocity, divergence, specific humidity, etc., and the special distribution of ISO have also differences with these from NCEP reanalysis data, which make it clear to develop this model to simulate the structure and spatial distribution of the ISO. 相似文献
13.
1. IntroductionThe adjustment of mass and velocity fields tosome imposed state of imbalance, constitutes a clas-sical problem in meteorology and oceanography. Tak-ing into account of the earth's rotation, the process isusually referred to as 'geostrophic adjustment', and isconcerned with the wind and density fields that persistafter gravity waves have radiated excess energy away(Rossby, 1937), and with the form of the gravity-waveenergy itself. Since the pioneer work of Rossby (1937),the stud… 相似文献
14.
Hydrogen peroxide (H2O2 ) concentrations were measured at two sites. One was on Lushan Mountain in May, 1987. The other was in Beijing in August, 1987 and in December, 1986. The automated fluorometric method was used for the determination of H2O2 . The concentrations of H2O2 ranged from approximately 0.50 to 4.32 ppb on Lushan Mountain. The concentrations of H2O2 ranged from approximately 0.05 to 1.49 ppb in August in Beijing, and it was only 0.01 ppb in December in Beijing. 相似文献
15.
ＮｕｍｅｒｉｃａｌＭｏｄｅｌｌｉｎｇｏｆｔｈｅＥｆｆｅｃｔｓｏｆＯｚｏｎｅｏｎｔｈｅＳｕｍｍｅｒＡｔｍｏｓｐｈｅｒｉｃＣｉｒｃｕｌａｔｉｏｎＷａｎｇＱｉａｎｑｉａｎ（王谦谦）；ＷａｎｇＹｉｎｈｕｉ（汪迎辉）；ＳｏｎｇＹｕ（宋煜）（Ｎａｍｉｎｇｉｎｓｔ... 相似文献
16.
This paper reviewed the main results with respect to the discovery of low center of total column ozone (TCO) over the Tibetan Plateau (TP) in summer, and its formation mechanism. Some important advances are summarized as follows: The fact is discovered that there is a TCO low center over the TP in summer, and the features of the background circulation over the TP are analyzed; it is confirmed that the TP is a pathway of mass exchange between the troposphere and stratosphere, and it influences the TCO low center over the TP in summer; models reproduce the TCO low center over the TP in summer, and the formation mechanism is explored; in addition, the analyses and diagnoses of the observation data indicate that not only there is the TCO low center over the TP in summer, but also TCO decrease trend over the TP is one of the strong centers of TCO decrease trend in the same latitude; finally, the model predicts the future TCO change over the TP. 相似文献
17.
G. T. Csanady 《大气与海洋》2013,51(1):18-19
A brief survey is given of the sources, the methods of injection into the atmosphere, and the mechanisms of deposition into bodies of water for various atmospheric pollutants which contribute significantly to the pollution of large bodies of water. Specific examples of the relative importance of atmospheric sources are included where data are available. Programs of the Canadian Atmospheric Environment Service in this field of research are outlined. 相似文献
18.
Yan Junyue 《大气科学进展》1997,14(2):277-287
ＯｂｓｅｒｖａｔｉｏｎａｌＳｔｕｄｙｏｎｔｈｅＯｎｓｅｔｏｆｔｈｅＳｏｕｔｈＣｈｉｎａＳｅａＳｏｕｔｈｗｅｓｔＭｏｎｓｏｏｎＹａｎＪｕｎｙｕｅ（阎俊岳）ＮａｔｉｏｎａｌＣｌｉｍａｔｅＣｅｎｔｅｒ，Ｂｅｉｊｉｎｇ１０００８１ＲｅｃｅｉｖｅｄＮｏｖｅｍｂ... 相似文献
19.
SHEN Wu ZHOU Jialing MA Jingxian CHEN Lianshou LUO Zhexian 《Acta Meteorologica Sinica》2007,21(3):290-301
In the context of advection dynamics,19 experiments(Exps.)are performed using a quasi-geostrophic barotropic vorticity equation model to explore the condition for the mergence of binary vortices and the self-organization of the larger scale vortex.Results show that the initial distance between the centers of binary vortices and the non-axisymmetric distributions of their initial vorticity are two factors affecting the mergence of binary vortices.There is a critical distance for the mergence of initial symmetric binary vortices, however,the mergence of initial non-axisymmetric binary vortices is also affected by the asymmetric structure of initial vortices.The self-organization processes in 19 experiments can be classified into two types:one is the merging of identical,axisymmetric binary vortices in which the interaction of the two vortices undergoes slowly change,rapid change,and the formation,stretching,and development of the filaments of vorticity, and the two vortices merge into a symmetric vortex,with its vorticity piled up in the inner region coming from the two initial vortices,and the vorticity of the spiral band in the outer region from the stretching of the filaments of the two initial vortices.And the other type is the merging of the two non-axisymmetric initial vortices of an elliptic vortex and an eccentric vortex in which the elliptic vortex,on the one hand, mutually rotates,and on the other hand moves towards the center of the computational domain,at the same time expands its vorticity area,and at last forms the inner core of resultant state vortex;and the eccentric vortex mutually rotates,meanwhile continuously stretches,and finally forms the spiral band of resultant state vortex.The interaction process is characteristic of the vorticity piled up in the inner core region of resultant state vortex originating from the elliptic vortex and the vorticity in spiral band mainly from the successive stretch and rupture of the eccentric vortex. 相似文献
20.
A photochemical model of the atmosphere constitutes a non–linear, non–autonomous dynamical system, enforced by the Earth’s rotation. Some studies have shown that the region of the mesopause tends towards non–linear responses such as period-doubling cascades and chaos. In these studies, simple approximations for the diurnal variations of the photolysis rates are assumed. The goal of this article is to investigate what happens if the more realistic, calculated photolysis rates are introduced. It is found that, if the usual approximations—sinusoidal and step fiunctions—are assumed, the responses of the system are similar: it converges to a 2–day periodic solution. If the more realistic, calculated diurnal cycle is introduced, a new 4–day subharmonic appear. 相似文献