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1.
An examination of typical tropospheric ozone variability on daily, monthly, annual and interannual timescales and instrumental precision indicates that the current ozonesonde network is insufficient to detect a trend in tropospheric ozone of 1% per year at the 2 level even at stations with records a decade in length. From a trend prediction analysis we conclude that in order to detect a 1% per year trend in a decade or less it will be necessary to decrease the time between observations from its present value of 3–7 days to 1 day or less. The spatial distribution of the current ozonesonde stations is also inadequate for determining the global climatology of ozone. We present a quantitative theory taking into account photochemistry, surface deposition, and wind climatology to define the effectively sampled region for an observing station which, used in conjunction with the instrumental precision and the above prediction analysis, forms the basis for defining a suitable global network for determining regional and global ozone climatology and trends. At least a doubling of the present number of stations is necessary, and the oceans, most of Asia, Africa, and South America are areas where more stations are most needed. Differential absorption lidar ozone instruments have the potential for far more frequent measurements of ozone vertical profiles and hence potentially more accurate climatology and trend determinations than feasible with ozonesondes but may produce a (fair weather) biased data set above the cloud base. A strategy for cloudy regions in which either each station utilizes both lidars and sondes or each station is in fact a doublet comprised of a near-sea-level lidar and a proximal-mountain-top lidar could serve to minimize this bias.  相似文献   
2.
To make a detailed test on the reliability and detection performance of the electrochemical concentra- tion cell (ECC) type ozonesonde which had been devel- oped and preliminarily evaluated by the authors, an inten- sive ozonesonde release experiment was held at two sites in Beijing and Changchun in June 2013. The results showed that the mean background current and its standard deviation were 0.03 (0.04) pA and 0.02 (0.03) pA in Bei- jing (Changchun). The average response time and its standard deviation were 27.8 s (30.4 s) and 4.0 s (3.7 s) in Beijing (Changchun). The ozone partial pressure profiles at both sites showed a central peak in the stratosphere and a side peak in the boundary layer. Large variation in ozone partial pressure was observed at the middle levels of the atmosphere (10-17 kin). A more marked gradient of ozone change was observed in Beijing (3.4 mPa km-1) at the lower atmosphere level, as compared to that in Changchun (0.4 mPa km-l). The results presented in this paper indicate that this self-developed ozonesonde shows a high level of reliability and good performance. The ozonsonde is expected to play an important role in opera- tional observations of ozone profiles.  相似文献   
3.
Tropopause folds are one of the key mechanisms of stratosphere-troposphere exchange (STE) in extratropical regions, transporting ozone-rich stratospheric air into the middle and lower troposphere. Although there have been many studies of tropopause folds that have occurred over Europe and North America, a very limited amount of work has been carried out over northeastern Asia. Ozonesondes produced by the Institute of Atmospheric Physics were launched in Changchun (43.9°N, 125.2°E), Northeast China, in June 2013, and observed an ozone-enriched layer with thickness of 3 km and an ozone peak of 180 ppbv at 6 km in the troposphere. The circulation field from the European Centre for Medium-Range Weather Forecasts Interim Reanalysis (ERA-Interim) dataset shows that this ozone peak was caused by a tropopause fold associated with a jet stream at the eastern flank of the East Asian trough. By analyzing the ozone data from the ozone monitoring instrument and Weather Research and Forecasting model with Chemistry (WRF-Chem) simulations, it was found that a high ozone concentration tongue originating from the lower stratosphere at high latitude (near central Siberia) intruded into the middle troposphere over Changchun between 5 and 8 km on 12 June 2013. The high-resolution WRF-Chem simulation was capable of describing events such as the tropopause fold that occurred on the cyclonic shear side of the jet stream. In addition, the TRAJ3D trajectory model was used to trace the origin of measured secondary ozone peaks in the middle troposphere back, for example, to stratospheric intrusion through the tropopause fold.  相似文献   
4.
该文介绍了中国科学院大气物理研究所(简称IAP)研制的电化学浓度电池(ECC)型臭氧(O3)探空仪基本性能测试和2013年上半年室外比对观测结果。结果表明:ECC的背景电流(Ibg)在0.1 μA以下或更低;测量O3的响应时间为21~26 s;NO2(SO2)使O3测值偏高(低);抽气泵低压泵效系数(Cef)在100 hPa高度以下为1.0左右,在该高度以上上升,10 hPa达到1.17±0.10,5 hPa达到1.28±0.16,性能略低于同类进口产品(1.055以下)。国产和进口仪器在气象探空或抽气泵等部件上具有良好兼容性;两者所测O3垂直分布廓线总体一致。IAP O3探空仪O3总量与Brewer光谱仪测值比值为0.9~1.1;Cef和Ibg订正有效降低了IAP O3探空仪在平流层低层与进口仪器测值的差别,这一订正对O3柱浓度在平流层和对流层的贡献分别为约15 DU和4~6 DU;在对流层,IAP O3探空仪测值与进口仪器间的绝对差别稳定且低于0.5 mPa;而平流层受泵效影响较明显。因此,建议IAP O3探空仪提高其Cef的稳定性,参与国际比对测试,国产气象探空平台数据接收处理增加必要的滤波技术以降低平流层探测数据(包括O3)的振荡。  相似文献   
5.
6.
In situ measurements of the vertical structure of ozone were made in Changchun(43.53?N, 125.13?E), China, by the Institute of Atmosphere Physics, in the summers of 2010–13. Analysis of the 89 validated ozone profiles shows the variation of ozone concentration in the upper troposphere and lower stratosphere(UTLS) caused by cut-off lows(COLs) over Changchun. During the COL events, an increase of the ozone concentration and a lower height of the tropopause are observed.Backward simulations with a trajectory model show that the ozone-rich airmass brought by the COL is from Siberia. A case study proves that stratosphere–troposphere exchange(STE) occurs in the COL. The ozone-rich air mass transported from the stratosphere to the troposphere first becomes unstable, then loses its high ozone concentration. This process usually happens during the decay stage of COLs. In order to understand the influence of COLs on the ozone in the UTLS, statistical analysis of the ozone profiles within COLs, and other profiles, are employed. The results indicate that the ozone concentrations of the in-COL profiles are significantly higher than those of the other profiles between ±4 km around the tropopause. The COLs induce an increase in UTLS column ozone by 32% on average. Meanwhile, the COLs depress the lapse-rate tropopause(LRT)/dynamical tropopause height by 1.4/1.7 km and cause the atmosphere above the tropopause to be less stable. The influence of COLs is durable because the increased ozone concentration lasts at least one day after the COL has passed over Changchun. Furthermore, the relative coefficient between LRT height and lower stratosphere(LS) column ozone is-0.62,which implies a positive correlation between COL strength and LS ozone concentration.  相似文献   
7.
北京上空大气臭氧垂直分布的特征   总被引:10,自引:1,他引:9  
利用我国自行研制的探空仪和地面接收设备首次较系统地获得了北京地区连续一年(2001年 3月至2002年 2月)的大气臭氧垂直分布资料。结果分析表明:①北京地区上空臭氧浓度极大值的季节均值的变化范围为15.1~16.7 mPa,其高度位于20.7~25.1km之间,极小值的季节均值的变化范围为 2.0~2.8 mPa,其高度在对流层顶附近。②边界层和平流层下部是臭氧浓度变化的活跃区域,并具有明显的季节变化,在边界层内夏季臭氧积分浓度高于冬季相应值的 1.7倍之多,而在平流层下部,冬季臭氧积分浓度则高于夏季的相应值。夏季边界层中臭氧浓度偏高,表明臭氧是北京地区夏季重要的污染气体之一。③北京上空臭氧垂直廓线的形态呈多样性,夏秋季节以单峰为主,冬春季节经常出现双峰和多峰结构;次峰出现的区域一般在10~18km高度范围内。  相似文献   
8.
南极中山站上空大气臭氧的直接测量   总被引:1,自引:0,他引:1       下载免费PDF全文
用球载电化学臭氧探空仪于1993年4-11月在南极中山站首次进行了臭氧垂直分布廓线的测量,大气臭氧测量系统由臭氧探空仪、地面接收装置和资料处理系统组成。该系统系中国科学院大气物理研究所和中国科学院空间科学与应用研究中心联合研制。本文介绍了该臭氧测量系统性能并给出部分典型测量结果  相似文献   
9.
From October 1995 to August 1996.a total of 50 ECC(electrochemical concentration cell)ozonesoundings were made in Xining(36.43°N,101.45°E,2296 m ASL)to study the distributionand seasonal characteristics of ozone profile,and intercompare the Brewer Umkehr ozone profilesobtained at Waliguan Baseline Station over the Qinghai Plateau.It was demonstrated that(1)Umkehr produced estimates of the ozone comparing with ECC profiles were accurate to better than25% in the 20—38 km altitude range,and where 23—33 km region was the most accurate,withinabout 15% of the ECC ozonesonde:(2)higher differences between Brewer Umkehr and ECCozonesonde occurred in the troposphere and lower stratosphere;and ozone amounts wereoverestimated in Umkehr layers 1,2 and 3,and were underestimated in Umkehr layers 6 and 7 byBrewer Umkehr method.  相似文献   
10.
Abstract

The ozonesonde stations at Uccle (Belgium) and De Bilt (Netherlands), separated by only 175?km, offer a unique opportunity to test the influence of different ozonesonde types and different correction strategies, as well as to detect the presence of inhomogeneities in the ozonesonde time series resulting from changes in sounding equipment (solution, radiosonde, ozonesonde, interface, sounding software, etc.). In particular, we highlight a 2.5 year period (beginning of 2007 to mid-2009) of anomalous high tropospheric ozone values measured by ozonesondes at Uccle and compare these with the observations from De Bilt. Because the ozone deviations are only observed in the free troposphere where ozone concentrations are relatively low, and not in the boundary layer or the stratosphere, this issue is directly related to the sensitivity of ozonesondes. Therefore, the effect of every instrumental change, even though small, during this 2.5 year anomalous period is analyzed considering a change in the radiosounding equipment, different ozonesonde batches, operational differences at the stations, differences on ascent and descent during the anomalous period; an environmental cause is also examined. Unfortunately, one single, specific cause for the observed high tropospheric ozone values at Uccle could not be identified. There are two explanations consistent with the observations and not ruled out by the analysis here: 1) the majority of the ozonesondes used at Uccle between March 2007 and August 2009 needed longer conditioning of their sensors and, therefore, behaved more accurately at low ozone concentrations during their descent or when used a second time, and 2) an environmental origin arising from a local difference in the air mass between Uccle and De Bilt and between the ascent and descent.  相似文献   
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