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1.
北极海冰的急剧消融在近年来欧亚大陆频发的低温事件中扮演着关键角色.秋季北极海冰的偏少对应着冬季欧亚大陆的低温天气,然而二者的联系在年代际和年际两种时间尺度上存在显著区别.本文运用1979—2012年哈德莱中心第一套海冰覆盖率(HadISST1)、欧洲中心(ERA_Interim)的2m温度、风场、海平面气压场、高度场等资料,分别研究了年代际和年际时间尺度上前期秋季北极海冰与欧亚冬季气温的联系.结果表明,欧亚和北极地区(0°—160°E,15°N—90°N)的冬季气温具有显著的年代际和年际变化.在年代际尺度上,温度异常分布在21世纪初由北极冷-大陆暖转为北极暖-大陆冷.这一年代际转折与前期秋季整个北极地区的海冰年代际减少联系密切.秋季北极全区海冰年代际偏少对应冬季欧亚大陆中高纬地区的高压异常,有利于北大西洋的暖湿气流北上和北极的冷空气南侵,造成北极暖-大陆冷的温度分布;在年际时间尺度上,温度异常分布主要由第一模态的年际变化部分和第二模态组成,且第一模态包含的年际变率信号也存在显著的年代际变化.年际尺度上全区北极海冰对欧亚冬季气温的影响远不及位于北冰洋西南边缘的巴伦支海、喀拉海和拉普捷夫海西部(30°E—120°E,75°N—85°N)的关键区海冰影响显著.关键区内海冰的偏少会引发冬季的北大西洋涛动负位相,导致北大西洋吹往欧亚大陆的暖湿气流减弱和欧亚大陆中高纬地区的气温偏低.  相似文献   

2.
本文基于1979—2014年臭氧总量的卫星遥感数据,利用多元线性回归模型对臭氧总量数据序列进行模拟计算,考察了北太平洋上空臭氧总量长期变化趋势及其影响因素的作用.结果表明,北太平洋地区大气臭氧总量长期变化呈现减少趋势,但是减少速率随季节和纬度带表现出差异性,在各纬度带臭氧峰值季节臭氧下降趋势最为显著.在0°—15°N地区臭氧高值出现在夏秋季节并在8月达到峰值,峰值月份臭氧年均下降率约为0.2DU/a;15°—30°N亚热带地区臭氧高值出现在春夏季并在5月达到峰值,峰值月份臭氧年均下降速率约为0.22DU/a;而在30°—45°N中纬度地区臭氧高值出现在冬春季并在2月达到峰值,峰值月份臭氧年均下降率0.75DU/a.在臭氧分布年平均态基础上,影响臭氧总量分布变化的因素主要有臭氧损耗物质(EESC)、太阳辐射周期(Solar)、准两年振荡(QBO)和厄尔尼诺-南方涛动(ENSO)等.其中,EESC导致臭氧损耗效应随着纬度升高而增大,在从低到高的三个纬度带损耗最大值分别为11DU、16DU和66DU;Solar增强导致臭氧增加,在三个纬度带的增加效应最大值分别为16DU、17DU和19DU;QBO@10hPa和QBO@30hPa对臭氧影响幅度基本在±10DU内波动,只有QBO@10hPa对30°—45°N区域的影响作用达到14DU,值得注意的是QBO影响作用随着纬度变化存在相位差异,在0°—15°N区域臭氧变化与QBO呈现相同相位,而在15°—30°N和30°—45°N区域臭氧变化与QBO呈现相反相位;ENSO对各个纬度带臭氧影响幅度也在±10DU内,ENSO影响作用在不同纬度带也存在相位差异,臭氧总量变化在0°—15°N、15°—30°N区域与ENSO相位相反,在30°—45°N区域与ENSO相位一致.  相似文献   

3.
本文利用NCEP/NCAR再分析资料,分析了1979~2008年北半球冬季哈得莱(Hadley)环流年际变化的特征,在此基础上,讨论了在观测海温驱动下大气环流模式的模拟结果.观测分析表明,近30年北半球冬季哈得莱环流年际变率的主导模态呈现出空间上的非均匀变化,哈得莱环流圈位于热带部分与其位于副热带部分的强度变化符号相反,这在表征其年际变化特征的另一指标——经向风垂直切变中亦有显著体现.大气环流模式AMIP积分试验结果表明,北半球冬季哈得莱环流强度的上述年际变化源于海温强迫.分析发现,热带中东太平洋和南印度洋暖海温距平强迫导致了哈得莱环流强度年际变化的主导模态呈现出空间上的非均匀变化.ElNio的局地作用和大气桥作用激发的太平洋局地哈得莱环流(30°S~30°N,150°E~90°W)和大西洋局地哈得莱环流(30°S~30°N,90°W~10°W)并非呈现出整体一致的变化,尽管二者纬向平均后分别使气候平均的哈得莱环流圈强度加强和减弱.ElNio遥强迫作用激发的西北太平洋反气旋(0°~30°N,100°E~150°E)使北半球Hadley环流圈强度减弱,ElNio和南印度洋暖海温距平共同强迫出的南印度洋反气旋(30°S~0°,60°E~100°E)使南半球Hadley环流圈的强度亦减弱.上述局地哈得莱环流的变化叠加后,因纬向平均的太平洋局地哈得莱环流强度在(副)热带部分的增强大(小)于纬向平均的大西洋局地哈得莱环流和西北太平洋、南印度洋局地哈得莱环流在(副)热带地区的减弱,结果使得哈得莱环流圈的强度在(副)热带部分偏强(弱);较之南半球,北半球强度变化稍强.因此,北半球冬季哈得莱环流年际变率的主导模态在空间上呈现出非均匀变化.  相似文献   

4.
贾建颖  刘毅 《地球物理学报》1954,63(10):3626-3639
利用1979年1月至2016年12月ERA-interim月平均再分析资料和CAMP全球月降水资料,分析夏季(6—8月)南亚高压下方500 hPa到100 hPa暖中心的时空分布,从三维结构来揭示夏季南亚高压暖心特征.回归分析进一步探讨青藏高原上空暖中心对全球大气环流产生的可能影响.结果表明:南亚高压在150 hPa达到最强,这一层也是异常冷暖中心分界面,150 hPa以下有一强大异常暖中心,异常暖中心位于300 hPa附近,150 hPa以上为异常冷中心,中心位置位于70 hPa附近.异常暖中心从500 hPa向上逐渐向西向北倾斜,异常暖中心面积200 hPa达最大,150 hPa异常暖中心消失,100 hPa以上转变为异常冷中心.500~200 hPa异常暖中心表现出不断增暖的长期趋势(1979—2016),100 hPa异常冷中心则表现出不断变冷的长期趋势(1979—2016).去掉长期趋势的时间序列表现出明显的"准两年振荡"特征,异常暖中心位置在纬向上较稳定,在经向上表现出年际的"东西振荡".300 hPa异常暖中心是整个南亚高压的关键层.300 hPa异常暖中心对全球其他变量场进行回归分析.高度回归场表明,青藏高原上空异常暖中心在北半球中高纬度高度场上激发出3波的行星波,波特征在对流层中上层表现明显,波振幅随高度增高不断加强,在对流层中下层逐渐减弱并消失.纬向风回归场在对流层中上层表现出横跨南北半球的波列,这个波列在200 hPa振幅最大.经向风回归场在北半球中纬度(30°N—60°N)表现出7波型,说明南北能量交换频繁.降水回归场表明,东亚地区长江中下游至日本降水偏少,而其南北两侧降水偏多.  相似文献   

5.
Hadley环流与北太平洋涛动的显著关系   总被引:4,自引:2,他引:2       下载免费PDF全文
利用NCEP/NCAR月平均再分析资料,分析了冬季(11~4月)Hadley环流与北太平洋涛动(NPO)的变化特征以及它们之间的关系.本文选取0°~30°N区域里最大质量流函数来描述北半球Hadley环流强度随时间的演变,利用(20°N, 180°~160°W) 和 (60°N, 180°~160°W) 区域平均的标准化海平面气压差代表NPO强度.结果表明,冬季北半球Hadley环流与NPO的变化形势非常一致,两者都具有显著的年际和年代际变化(70年代前处于负位相,80年代之后处于正位相),同时还呈现出明显的增强趋势.Hadley环流变化与NPO异常的关系非常密切,在年际和年代际时间尺度上都具有显著的正相关.这种强相关性在大气环流场上可以得到很好的印证.研究还揭示,太平洋地区10°~30°N下沉支和40°~60°N上升支的异常运动可能是这种关系存在的主要内在原因.  相似文献   

6.
利用NCEP/NCAR再分析风场资料和NOAA海表温度(SST)资料,分析了冬、夏季Hadley环流的变化特征及其与热带海温在年际、年代际尺度上的关系. 结果表明,冬季北半球Hadley环流强度具有明显的年际和年代际变化,同时还呈现出明显的增强趋势. 伴随着Hadley环流的加强,环流中心位置南移,高度上升;夏季南半球Hadley环流变化主要表现为强、弱、强的年代际振动,没有明显的线性趋势. 研究还显示冬季Hadley环流与Nino3区SST正相关,这种相关性具有年代际变化特征. 年际尺度上,冬季北半球Hadley环流与Nino3区SST正相关;夏季南半球Hadley环流与Nino3区SST负相关,即当赤道中东太平洋SST异常偏暖(冷)时,冬、夏季Hadley环流变强(弱).  相似文献   

7.
孟加拉湾夏季风爆发的判断指标及其年际特征   总被引:1,自引:0,他引:1       下载免费PDF全文
晏红明  孙丞虎  王灵  李蕊  金燕 《地球物理学报》2018,61(11):4356-4372
利用高低层大气环流、OLR(向外长波辐射)、CMAP降水、SST(海表温度)等资料分析了孟加拉湾地区3—5月多年气候平均大气环流及不同要素的演变特征,定义了一个新的孟加拉湾夏季风(BOBSM,下同)爆发指标为孟加拉湾地区(5°N—15°N,90°E—97.5°E)850 hPa和200 hPa纬向风区域平均的变化同时满足U850 > 3 m·s-1和U200 < -5 m·s-1,并持续5天的第一天即作为BOBSM爆发日期.该季风指数有明确的天气学意义,可以反映孟加拉湾低层西南风持续稳定和南亚高压在青藏高原建立早晚的特征.文章进一步分析了BOBSM爆发的年际特征及其前兆海洋信号特征,结果表明:1981—2010年BOBSM爆发的平均日期为5月10日,季风爆发有显著的年际波动,爆发最早在1999年(4月11日)和最晚在1968年(6月1日),年代际尺度上表现为由爆发偏晚至偏早的变化趋势;BOBSM爆发早(晚)与热带印度洋地区850 hPa的越赤道气流和西风异常加强(减弱),以及200 hPa青藏高原南亚高压的季节性建立偏早(晚)等密切联系;前期冬季赤道西太平洋的海温冷(暖)变化对BOBSM爆发早(晚)有很好的指示意义,前期冬季海温偏高(低)有利于季风偏早(晚),其影响的主要途径是通过热源变化激发纬向垂直环流及其热带印度洋和太平洋低层环流异常,进而影响季风爆发早晚.  相似文献   

8.
火山活动对北半球平流层气候异常变化的影响   总被引:8,自引:0,他引:8  
文中利用逐次滤波法滤除北半球平流层70 hPa约15~22 km高空大气温度异常变化中太阳活动的影响之后,进一步分析了火山活动的气候效应,分析结果表明,火山活动能引起平流层较大幅度增温,对于北半球70hPa高空气候异常变化的影响超过了总方差的30%;火山活动影响最显著的高度是平流层70 hPa约15~22 km高空,由此高度向上或向下,火山活动的影响都逐渐减小;火山活动引起平流层大气升温的同时还将引起对流层大气降温,其分界线大致位于对流层顶300 hPa附近;强火山爆发如皮纳图博火山爆发、阿贡火山爆发和堪察加北楮缅奴等火山爆发是引起未来两年左右平流层中下层温度异常变化最重要的因素,其方差贡献率超过百分之五十三!;火山喷发高度越高,引起平流层增温效应的层次也越高;北半球大气温度异常变化对南半球火山活动响应的滞后时间比北半球火山活动长. 平流层高空气候异常变化还具有显著的22年变化周期,分析认为是大气温度场对太阳磁场磁性周期22年异常变化的响应,其方差贡献率超过9%.  相似文献   

9.
利用1979~2010年NCEP-DOE 2逐日再分析资料,以北半球春季平流层极夜急流核心纬带(65°~75°N)纬向平均纬向风最后一次转为东风的日期定义为春季平流层最后增温事件(SFW)的爆发日期,研究发现,SFW事件平均在4月中下旬发生,且由平流层高层向低层依次滞后,10 hPa的SFW爆发平均超前50 hPa约13天;爆发当日伴随纬向风场时间变率和行星波辐合的最大值,平流层环流实现由冬向夏的季节转换;过去32年以来SFW的爆发早晚具有显著的年际变化,最早的SFW事件发生在3月中旬,最晚的SFW事件在5月下旬才出现.合成分析表明,SFW爆发偏早(晚)年的春季,纬向风场由西风向东风的转变更为快速(缓慢),爆发前5天至爆发后5天,30 hPa纬向风减小约20 m s-1(5 m s-1),伴随的平流层行星波活动也相对较强(弱);表现在环流异常场上,SFW爆发前后平流层极区环流异常呈反(同)位相分布,表明发生较早的SFW事件主要受波强迫驱动而伴随爆发性增温,而发生较晚的SFW事件则更反映了极涡的季节变化特征.无论SFW偏早还是偏晚年,爆发后极区平流层与对流层温度异常之间均呈反位相关系,反映了SFW爆发事件中的平流层-对流层动力耦合特征.另外,在20世纪90年代中期前后,SFW爆发日期还存在明显的年代际转折,90年代中期之前SFW平均发生日期较之后约偏早11天;与之相联系的是冬末、春初行星波活动在90年代中期之前偏强,而在90年代中期之后有偏弱趋势.  相似文献   

10.
利用ECMWF和HALOE资料,分析了1991~2002年两种资料中温度垂直廓线、平方差水平分布,并通过线性趋势分析方法分析了平流层不同高度温度变化趋势的差异.研究结果表明:在中低纬度地区,10 hPa以下两种资料中温度垂直廓线非常吻合;10~2 hPa高度,HALOE资料中温度比ECMWF资料中温度要高;1 hPa高度上,两种资料也有比较小的差异.在南北半球的中高纬度地区,温度的差异比较明显,整个平流层中,HALOE资料中温度比ECMWF资料中温度要高.平流层中温度的水平分布差异随着高度而增大.中低纬度地区温度差异相对较小,南北半球50°以上地区差异比较大.在平流层的中低层100 hPa、50 hPa和10 hPa高度,两种资料中温度的变化趋势一致,但是HALOE资料中温度的递减趋势要更明显.在平流层高层2 hPa,1996年后两种资料中温度的变化趋势相反.本研究将为平流层温度研究的资料选择提供一定的依据.  相似文献   

11.
《Journal of Atmospheric and Solar》2003,65(11-13):1235-1243
The aim of the present paper is to study the solar response in the vertical structure of ozone and temperature over the Indian tropical region and a search for any mutual relationship between their solar coefficients on a decadal scale in the lower stratosphere. For the purpose, the data obtained by ozonesonde and Umkehr methods for the lower stratospheric ozone and that of the total ozone amount from Dobson spectrophotometer during the period 1979–2001 have been analyzed. These data are analyzed using the multi-functional regression model, which takes into account most of the known natural and anthropogenic signals. The NCEP- and MSU-satellite data for the temperature over this region have been used. Results indicate an in-phase correlation of around 0.5 between ozone and solar flux (F10.7) in the vertical structure over the equatorial station, Trivandrum (8.3°N) but no significant correlation over Pune (18.3°N). The solar components of ozone and temperature indicate an in-phase but poor correlation in the lower stratospheric altitudes over both stations. However, when total ozone content data is analyzed, it indicates a very high correlation (⩾0.9) between the solar components of ozone and temperature. The solar trend in the vertical distribution of ozone is found to be of the order of 5–25% per 100 units of F10.7 solar flux for Trivandrum but it is relatively smaller (1.6–15.2%) over Pune. The solar dependence of temperature is found to be quite significant for the entire Indian tropical region with not much latitudinal variation.  相似文献   

12.
Total ozone anomalies (deviation from the long-term mean) are created by anomalous circulation patterns. The dynamically produced ozone anomalies can be estimated from known circulation parameters in the layer between the tropopause and the middle stratosphere by means of statistics. Satellite observations of ozone anomalies can be compared with those expected from dynamics. Residual negative anomalies may be due to chemical ozone destruction. The statistics are derived from a 14 year data set of TOMS (Total Ozone Mapping Spectrometer January 1979-Dec. 1992) and corresponding 300 hPa geopotential (for the tropopause height) together with 30 hPa temperature (for stratospheric waves) at 60°N. The correlation coefficient for the linear multiple regression between total ozone (dependent variable) and the dynamical parameters (independent variables) is 0.88 for the zonal deviations in the winter of the Northern Hemisphere. Zonal means are also significantly dependent on circulation parameters, besides showing the known negative trend function of total ozone observed by TOMS. The significant linear trend for 60°N is 3 DU/year in the winter months taking into account the dependence on the dynamics between the tropopause region and the mid-stratosphere. The highest correlation coefficient for the monthly mean total ozone anomalies is reached in November with 0.94.  相似文献   

13.
Examined are temperature and ozone variations in the Northern Hemisphere stratosphere during the period 1958–77, as estimated from radiosondes rocketsondes, ozonesondes, and Umkehr measurements. The temperature variation in the low tropical stratosphere is a combination of the variation associated with the quasi-biennial oscillation, and a variation nearly out of phase with the pronounced 3-yearly temperature oscillation (Southern Oscillation) present in the tropical troposphere since 1963. Based on radiosonde and rocketsonde data, the quasibiennial temperature oscillation can be traced as high as the stratopause, the phase varying with both height and latitude. However, the rocketsonde-derived temperature decrease of several degrees Celsius in the 25–55 km layer of the Western Hemisphere between 1969 (sunspot maximum) and 1976 (sunspot minimum) is not apparent in high-level radiosonde data, so that caution is advised with respect to a possible solar-terrestrial relation.There has been a strong quasi-biennial oscillation in ozone in the 8–16 km layer of the north polar region, with ozone minimum near the time of quasi-biennial west wind maximum at a height of 20 km in the tropics. A quasi-biennial oscillation in ozone (of similar phase) is also apparent from both ozonesonde data and Umkehr measurements in 8–16 and 16–24 km layers of north temperate latitudes, but not higher up. Both measurement techniques also suggest a slight overall ozone decrease in the same layers between 1969 and 1976, but no overall ozone change in the 24–32 km layer. Umkehr measurements indicate a significant 6–8% increase in ozone amount in all stratospheric layers between 1964 and 1970, and in 1977 the ozone amount in the 32–46 km layer was still 4% above average despite the predicted depletion due to fluorocarbon emissions. The decrease in ozone in the 32–46 km, layer of mid latitudes following the volcanic eruptions of Agung and Fuego is believed to be mostly fictitious and due to the bias introduced into the Umkehr technique by stratospheric aerosols of volcanic origin. Above-average water vapor amounts in the low stratosphere at Washington, DC, appear closely related to warm tropospheric temperatures in the tropics, presumably reflecting variations in strength of the Hadley circulation.  相似文献   

14.
利用1979~1992年卫星TOR对流层臭氧数据库资料,以及同期太阳辐照度数据序列,考察青藏高原对流层臭氧含量变化与太阳辐射周期变化之间的关系.分析表明,青藏高原对流层臭氧分布表现出与太阳辐照度相同的变化趋势,存在着明显的太阳周期变化特征.逐月线性回归分析表明,太阳辐照度增加导致青藏高原对流层臭氧增加的正效应.在太阳周期内,太阳辐射增加可使青藏高原对流层臭氧、平流层臭氧和臭氧总量分别增加1.31、4.97、6.628DU,或4.07%、2.04%、2.28%.该特征与赤道太平洋地区完全相反,分析产生差异的原因,至少应包括两方面因素:一是背景大气NOX和水汽含量的差异;二是青藏高原频繁发生的平流层-对流层大气物质交换和输送.  相似文献   

15.
Recent observations suggest that there may be a causal relationship between solar activity and the strength of the winter Northern Hemisphere circulation in the stratosphere. A three-dimensional model of the atmosphere between 10–140 km was developed to assess the influence of solar minimum and solar maximum conditions on the propagation of planetary waves and the subsequent changes to the circulation of the stratosphere. Ultraviolet heating in the middle atmosphere was kept constant in order to emphasise the importance of non-linear dynamical coupling. A realistic thermo-sphere was achieved by relaxing the upper layers to the MSIS-90 empirical temperature model. In the summer hemisphere, strong radiative damping prevents significant dynamical coupling from taking place. Within the dynamically controlled winter hemisphere, small perturbations are reinforced over long periods of time, resulting in systematic changes to the stratospheric circulation. The winter vortex was significantly weakened during solar maximum and western phase of the quasi-biennial oscillation, in accordance with reported 30 mb geopotential height and total ozone measurements.  相似文献   

16.
Temperature structures in the height range of 0–30 km over Pan Chiao (25°N, 121°E) in northern Taiwan were studied for the period 1990–1995 using radiosonde data. The purpose of this study is to see the annual variation of tropopause temperature and height and also to study local temperature perturbations caused by the series of volcanic eruptions at Mount Pinatubo in June 1991. While the annual variation in the tropopause height and temperature is clearly observed, we found a large increase in the temperature at the tropopause and in the lower stratospheric region during the year 1992. The tropopause is warm during the year 1992 and temperature increase at the tropopause is nearly 6°C in January 1992. The annual average temperature at the lower stratosphere during 1992 shows an increase of 2°C from the normal trend. The effects of Pinatubo are in general different in the troposphere and stratosphere.  相似文献   

17.
Spänkuch  D.  Döhler  W.  Kubasch  H. 《Pure and Applied Geophysics》1973,106(1):1208-1218
Summary The correlation matrix for the vertical ozone distribution and the temperature-ozone cross-correlation matrix, which was calculated from ozone soundings made over Berlin between 1967 and 1970, the statistical structure of the vertical ozone profile (correlation coefficients, average profiles, average standard deviation, relative variability) was derived for the three ozone seasons. The partial ozone pressure does not at all heights follow a normal distribution (e. g. at tropopause level). Generally, the correlation between tropospheric and stratospheric ozone is rather poor. In some layers the highest correlation coefficients, i.e. –0.3 and +0.4, occur in autumn (October to December) and in winter and spring (January to April). The correlation between the ozone amounts of various stratospheric layers is distinct in autumn, less distinct in summer (May to September) and entirely missing from January to April. Conspicuous cross-correlations between temperature and ozone have been found for all three seasons. a) With a negative correlation between tropospheric temperature and middle tropospheric to middle stratospheric ozone (maximum up to –0.8); b) with a rather strong positive correlation between the ozone amount and the temperature in the lower stratosphere (maximum up to +0.84); c) with a positive correlation between the ozone amount of the middle stratosphere and the temperature of the middle stratosphere (maximum up to +0.8). The highest correlation coefficients occur in autumn.  相似文献   

18.
冬季太阳11年周期活动对大气环流的影响   总被引:2,自引:0,他引:2       下载免费PDF全文
刘毅  陆春晖 《地球物理学报》2010,53(6):1269-1277
利用气象场的再分析资料和太阳辐射活动资料,对太阳11年周期活动影响北半球冬季(11月~3月)大气环流的过程进行了统计分析和动力学诊断.根据赤道平流层纬向风准两年振荡(QBO)的东、西风状态对太阳活动效应进行了分类讨论,结果表明:东风态QBO时,太阳活动效应主要集中在赤道平流层中、高层和南半球平流层,强太阳活动时增强的紫外辐射加热了赤道地区的臭氧层,造成平流层低纬明显增温,同时加强了南半球的Brewer-Dobson(B-D)环流,引起南极高纬平流层温度增加;而北半球中高纬的环流主要受行星波的影响,太阳活动影响很小.西风态QBO时,太阳活动效应在北半球更为重要,初冬时强太阳活动除了加热赤道地区臭氧层外,还抑制了北半球的B-D环流,造成赤道平流层温度增加和纬向风梯度在垂直方向的变化,从而改变了对流层两支行星波波导的强度;冬末时在太阳活动调制下,行星波向极波导增强,B-D环流逐渐恢复,造成北半球极地平流层明显增温,同时伴随着赤道区域温度的下降.  相似文献   

19.
The global structures of annual oscillation (AO) and semiannual oscillation (SAO) of stratospheric ozone are examined by applying spherical harmonic analysis to the ozone data obtained from the Nimbus-7 solar backscattered UV-radiation (SBUV) measurements for the period November 1978 to October 1980. Significant features of the results are: (1) while the stratospheric ozone AO is prevalent only in the polar regions, the ozone SAO prevails both in the equatorial and polar stratospheres; (2) the vertical distribution of the equatorial ozone SAO has a broad maximum of the order of 0.5 (mixing ratio in g/g) and the maximum appears earlier at high altitude (shifting from May [and November] at 0.3 mb [60 km] to November [and May] at 40 mb); (3) above the 40 km level, the maximum of the polar ozone SAO shifts upward towards later phase with altitude with a rate of approximately 10 km/month in both hemispheres; (4) vertical distributions of the polar ozone AOs and SAOs show two peaks in amplitude with a minimum (nodal layer) in between and a rapid phase change with altitude takes place in the respective nodal layers; and (5) the heights of the ozone AO- and SAO-peaks decrease with latitude. The main part of AOs and SAOs of stratospheric ozone including hemispheric asymmetries is ascribable to: (i) temperature dependent ozone photochemistry in the upper stratosphere and mesosphere, (ii) variations of radiation field in the lower stratosphere affected by the annual cycle of solar illumination and temperature in the upper stratosphere and (iii) meridional ozone transport by dynamical processes in the lower stratosphere.  相似文献   

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