NUMERICAL SIMULATION OF OZONE DISTRIBUTIONS AND ITS VARIATION MECHANISM

A 2-D global chemistry-transport model is set up in this paper.The model simulates theatmospheric ozone distributions well with specified dynamical conditions.The analysis of ozonevariation mechanism shows that ozone is chemically in quasi-equilibrium except for the polar nightregion where the variation of ozone concentration is under the control of dynamical processes,thatthe oxygen atoms which produce ozone are mainly provided by the photolysis of O_2 in the upperstratosphere and by the photolysis of NO_2 in the lower stratosphere and the troposphere.and thatthe ozone is destroyed mainly by NO_x:the reactions between NO_x and O_3 and the odd oxygen cyclecontribute 80% to more than 90% of the ozone destruction.     

NUMERICAL SIMULATION OF OZONE DISTRIBUTIONS AND ITS VARIATION MECHANISM*

A 2-D global chemistry-transport model is set up in this paper.The model simulates the atmospheric ozone distributions well with specified dynamical conditions.The analysis of ozone variation mechanism shows that ozone is chemically in quasi-equilibrium except for the polar night region where the variation of ozone concentration is under the control of dynamical processes,that the oxygen atoms which produce ozone are mainly provided by the photolysis of O₂ in the upper stratosphere and by the photolysis of NO₂ in the lower stratosphere and the troposphere.and that the ozone is destroyed mainly by NO_x:the reactions between NO_x and O₃ and the odd oxygen cycle contribute 80% to more than 90% of the ozone destruction.     

MEASUREMENTS AND MODEL SIMULATIONS OF SURFACE OZONE VARIATIONS AT DIFFERENT BACKGROUND CONCENTRATIONS OF THE PRECURSORS*

Ozone photochemical production and loss in very different environments at Waliguan baseline station and Lin'an background station were simulated by using the measurement data and photochemical box model.The results show that net ozone photochemical production rate is negative,about 0.5 ppb/d,at Waliguan baseline sation,because of very low precursor concentrations.But at Lin'an background station,the net photochemical ozone production is positive,about 2-3 ppb/h.which is very closed with the measurement at Lin'an.That means ozone production was controlled by photochemical reactions at Lin'an background station,because of the higher precursor concentrations.The net destruction rate,at Waliguan Mt.,is not large,so that future increase in anthropogenic emission of reactive nitrogen will lead to larger production rates of steady-state O₃ concentration.     

上海夏季近地面臭氧浓度及其相关气象因子的分析和预报

为了揭示城市近地面臭氧浓度的变化特征及其相关气象因素,尝试进行近地面臭氧浓度预报。通过对2005年夏季（6～9月上旬）上海徐家汇地区近地面臭氧的观测与分析,建立了用于夏季臭氧浓度预报和高浓度臭氧污染事件预警的一种简便、实用的统计回归方法。结果表明：天气条件对臭氧形成具有明显的作用,臭氧浓度晴天最大、多云天次之、阴雨天最小;臭氧具有明显的日变化特征,12：00～14：00之间为最大值,凌晨3：00～5：00之间有一很小的次峰,5：00～6：00之间为最小值。产生高浓度臭氧污染是多项因子的综合结果,一般在高压系统的影响下,晴天少云,紫外辐射较强,相对湿度较低,气温较高,地面和高空吹偏北风,且风速较小的情形时容易产生高浓度臭氧污染。引进高浓度臭氧潜势指数和风向影响指数两个指标,并综合考虑多种气象要素,通过逐步回归建立的臭氧浓度预报方程,对逐日最大臭氧浓度具有较好的拟合效果和可预报性。     

NUMERICAL SIMULATION OF THE FORMATION MECHANISM OF THE ANTARCTIC OZONE HOLE

The global zonally averaged atmospheric chemistry model is developed in this paper.Theformation mechanism of the Antarctic ozone hole is numerically simulated using the model to checkthe viewpoints on the formation mechanism.The results show that:(1)The Antarctic ozone hole is a special phenomenon resulting from the heterogeneousreactions on the surface of the polar stratospheric cloud particles,under the special conditions oftemperature and circulation in Antarctic spring.The heterogeneous reactions reduce the NO_2concentration,resulting in the decrease of ozone production rate.The ozone content decreaseswhen its production is less than its destruction.This is the direct cause for the formation of theAntarctic ozone hole.(2)The impact of the polar vortex on the transport of trace species is not the determinativefactor in the formation of the Antarctic ozone hole.but makes the intensity of the ozone holechanged.(3)The solar cycles have negligible influence on the intensity of the Antarctic ozone holethrough photochemical reactions.     

南半球臭氧变化气候效应的数值模拟

采用一个陆气耦合的９层谱模式模拟了南半球臭氧减少所产生的气候效应。数值试验结果表明,南半球臭氧的减少不仅对南半球温度场的 大气环流有影响,而且对北半球的温度场结构和大气环汉也有一定的影响。其气候效应具有全球性。南半球臭氧减少总体上可以使平流层中层以上大气降温、平流层低层增温、对流层顶附近降温。此外,在北半球冬半年期间,南半球臭氧的减少可使南北半球的副热带西风急流都减弱,极锋急流都增强;在北半球夏半     

NUMERICAL SIMULATION OF THE SEASONAL VARIATION OF TROPOSPHERIC OZONE OVER CHINA

An updated version of the Regional Acid Deposition Model(RADM)driven by meteorologicalfields derived from Chinese Regional Climate Model(CRegCM)is used to simulate seasonal variationof tropospheric ozone over the eastern China.The results show that:(1)Peak O_3 concentration moves from south China to north China responding to the changing ofsolar perpendicular incidence point from south to north.When solar perpendicular incidence pointmoves from north to south,so does the peak O_3 concentration.(2)In the eastern China.the highest O_3 month-average concentration appears in July.thelowest in January and the medium in April and October.The pattern mainly depends on the solarradiation,the concentration of O_3 precursors NO_x and NMHC and the ratio of NMHC/NO_x.(3)Daily variations of O_3 over the eastern China are clear.Namely,O_3 concentrations rise withthe sun rising and the maximums appear at noon.then O_3 concentrations decrease.The highest dailyvariation range of O_3 appears in summer(40×10~(-9) in volume fraction)and the lowest in winter(20×10~(-9) in volume fraction).(4)Daily variations of O_3 over the western China are not clear.The daily variation range of O_3 isless than 10×10~(-9) in volume fraction.     

非甲烷碳氢化合物的光化学臭氧生成潜势的数值模拟研究

应用大气光学模式研究了不同ＮＭＨＣ／ＮＯｘ比值时,各ＮＭＨＣ物种的光化学臭氧生成潜势指数（Ｉｐｏｃｐ值）,探讨了在较高ＮＭＨＣ／ＮＯｘ比值时,各ＮＭＨＣ物种Ｉｐｏｃｐ值随时间的变化规律。结果表明：不同结构、种类的ＮＭＨＣ对光化学臭氧贡献有很大差异;各ＮＭＨＣ物种的Ｉｐｏｃｐ值随ＮＭＨＣ／ＮＯｘ比值、,光化学反应的时间尺度变化而系统性地变化。ＮＯｘ烯烃、芳烃和醛类的活性高寿命短,输送距离有限,主要表     

PRELIMINARY ANALYSIS OF THE VARIATIONS OF SURFACE OZONE AND NITRIC OXIDES IN LIN''''AN

The observational results in Lin'an show the elevated average concentrations of surface ozone and Nitric Oxides(NO_x)in the rural area in the eastern mid-latitudes of China.The mechanism of its variations was explained by the theo-retical analysis.In the case of breeze,the photochemical reactions controlled by solar radiation is the determined factorsaffecting the variations of the surface O_3 and NO_x.A study of the correlation between NO_x and SO_2 demonstrates thatthe biomass burning is an important local emission source of NO_x.     

VARIATION OF TOTAL OZONE IN LOWER LATITUDE AREA OF CHINA

By using the observational O3 data of Kunming and Hong Kong during the period of 1997 – 2001, the paper studies the distribution and variation of total ozone in low latitude region of China. The study shows that the characteristics of variation in Kunm…     

中国低纬度地区大气臭氧总量的变化特征

分析研究了位于我国低纬地区不同经度的昆明与香港两个站点上空的臭氧分布与演变状况,得出了中国低纬度地区大气臭氧总量的时空演变特征.研究结果显示:(1)香港与昆明两地臭氧的时间变化特征极为相似;(2)整个中国低纬地区的大气臭氧的时间变化趋势是非常一致的,在空间上呈现出东高西低的特征;(3)我国低纬地区的大气臭氧总量在夏季出现极大值,在冬季出现极小值.计算结果还表明,昆明的臭氧总量要小于其所在纬圈的平均值.     

CALCULATION OF AIR-MASS FACTORS FOR O_3

In conversion of the integrated slant column amount of atmospheric ozone(O_3)measured bythe ground-based spectrometer technique during twilight to the vertical quantity,the air-massfactor(AMF)is an important parameter.In this work,calculations of AMF for ozone wereperformed for different atmospheres.It is shown that the O_3 AMF has seasonal variations with theminimum at the beginning of spring and the maximum in summer due to the seasonal change in thevertical distributions of O_3.A parameterization relation is obtained between O_3 AMF and opticalthickness of stratospheric volcanic aerosols based on the Monte-Carlo radiative transfersimulations.     

中国地区对流层臭氧变化和分布的数值研究

利用三维中尺度非静力模式ＭＭ５和化学模式,对１９９４年８月１６～１８日,１９９５年１月７～９日冬夏两个不同时期中国大陆大气对流层臭氧及其前体物质的分布进行了数值模拟。同时深入地分析了青藏高原地区夏季对流层臭氧的分布。模拟结果地面臭氧和ＮＯｘ的分布与观测结果基本一致,人类活动和光化过程是决定地面臭氧和ＮＯｘ的主要因子。对流层臭氧浓度的分布与气流的辐合辐散存在较好的对应关系,辐合区臭氧浓度较高,辐散区臭氧浓度较低。夏季,青藏高原中低空存在很强的辐合气流,使周边臭氧向高原辐合;而高原高空,受南亚高压控制存在很强的反气旋环流,臭氧由高原向周边辐散。冬季,受西风气流控制,臭氧分布表征大尺度特征。西风急流区臭氧浓度偏低,而急流两侧臭氧浓度偏高。     

NUMERICAL INVESTIGATION OF QBO IN OZONE

In this paper, a two-dimensional primitive equation model, coupling dynamical, radiative andphotochemical processes, is used to simulate the quasi-biennial oscillation (QBO) in ozone. TheQBO in total ozone has been successfully simulated when the forcing of equatorial stratosphericQBO in zonal wind is imposed. The simulated characters of QBO in ozone are in close agreementwith those observed. We further analyzed the mechanism of formation and maintenance of QBO inozone. In the different phases of QBO in equatorial stratospheric wind field, the global circulationhas so great difference that it makes the effects of advection transfer and eddy transfer present aquasi-biennial periodical variation. Chemical effect and dynamical effect are basically out-of-phase.They together form and maintain the QBO in ozone. Total variation rate is a tiny difference of thetwo large amounts. At the lower level of middle-high latitudes, however, it has a phase differenceof about 1-2 months between dynamical and negative chemical effects, where the dynamical effectis comparatively greater. QBO in ozone has no clear counter effects on atmospheric circulation. The experiment resultsshow that the effects of QBO in ozone on temperature field and wind field are very small.     

城市低层大气臭氧生成的模拟研究

利用一个城市边界层臭氧模式，以南京市为对象，研究了臭氧在城市低层大气中的形成机制和规律，得出了南京市18个交通点的日臭氧浓度最大值的分布图。结果表明，南京市白天有相当长的时间是处于臭氧超标的状态，不少交通点的日最大臭氧浓度值是标准的2－3倍。文章还模拟了PAN，OH自由基和HCHO这三种重要物种的日变化规律。同时，本文选择南京市东郊的紫金山风景区，实次探讨了植物排放有机物对臭氧生成的贡献。从模式的模拟研究可得，与人为因素相比，植物排放对臭氧生成的作用也是不可忽视的，值得作深入一步的探讨。     

近十五年全球臭氧变化

利用卫星观测臭氧总含量ＴＯＭＳ（第７版）资料,在剔除季节变化后对全球６０°Ｓ－６０°Ｎ范围首先进行了沿纬度分布的线性趋势和周期分析。结果表明：自本世纪７０年代末,各纬带上的臭氧总量都呈下降趋势,强度随纬度升高而加剧,并发现总体上北半球臭氧的下降趋势较南半球更加明显;同时证实了准两年振荡是臭氧变化中除年周期外最显著的周期。并对臭氧变化中的准两年振荡作了遥相关分析;发现准两年振荡在强度和位相上基本呈纬向分布并主要表现出赤道对称的特征。１３５～１７０°Ｅ地区臭氧总量变化所表现出的不同于其它地区的原因可能是这一地区常年频繁出现的对流活动;而臭氧总量下降趋势表现出的北半球同纬度地区均大于南半球的南北半球差异可能是由两半球人类活动的差异引起     

EFFECTS OF SOLAR FLARE ON THE MIDDLE ATMOSPHERE

The SME satellite data of solar UV radiation and mesospheric ozone during solar flare in 1982are analyzed.The results show that the Ha line index used in the solar flare classification is not aproper parameter for studying the effects of solar activity on the photochemical process in themiddle atmosphere.     

1979—2011年热带对流层顶高度线性趋势变化的因子贡献及其年际变率成因探讨

利用美国国家环境预报中心/大气研究中心(NCEP/NCAR)再分析资料分析了近30年(1979—2011年)热带(0~360 °E,20 °S~20 °N)对流层顶高度变化,结果显示其高度有明显的线性上升趋势,近30年气压下降了3.5 hPa。其中对流、臭氧和对流层温度的贡献分别为13.3%、27.26%和57.31%。在去除线性趋势后,热带对流层顶气压表现出了显著的年际变率,主要周期峰值为18.2、28.6和40个月。其中臭氧和热带对流层温度都对18.2个月的周期有贡献,而臭氧和热带对流层温度18.2个月的周期很可能是由北半球的季风环流引起的;28.6个月的周期主要源于臭氧总量的准两年周期变化,而后者是由热带平流层低层纬向风场的准两年振荡引起的;热带对流层顶气压40个月的周期似乎源于ENSO循环引起的对流层温度变化。      

CALCULATION OF AIR-MASS FACTORS FOR O3

In conversion of the integrated slant column amount of atmospheric ozone(O₃) measured by the ground-based spectrometer technique during twilight to the vertical quantity,the air-mass factor(AMF) is an important parameter.In this work,calculations of AMF for ozone were performed for different atmospheres.It is shown that the O₃ AMF has seasonal variations with the minimum at the beginning of spring and the maximum in summer due to the seasonal change in the vertical distributions of O₃.A parameterization relation is obtained between O₃ AMF and optical thickness of stratospheric volcanic aerosols based on the Monte-Carlo radiative transfer simulations.     

臭氧总量对太阳活动长期变化的响应

通过对１９５９－１９８５年逐年的年平均臭氧总量在１０°，２０°，．．．，７０°Ｎ各纬圈进行极大熵谱分析及回归分析，发现臭氧总量对太阳活动１１年和２２年周期性变化的响应在北半球各纬圈并非一致。在低纬和高纬度地区，臭氧总量对太阳活动２２年周期性变化的响应较强，对１１年周期变化的响应较弱；在中纬度地区则与此相反，臭氧总量对太阳活动１１年周期性变化的响应比２２年周期性变化的响应强。