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61.
The 1981–82 Solar Mesosphere Explorer (SME) mission is described. The SME experiment will provide a comprehensive study of mesospheric ozone and the processes which form and destroy it. Five instruments will be carried on the spinning spacecraft to measure the ozone density and its altitude distribution from 30 to 80 km, monitor the incoming solar ultraviolet radiation, and measure other atmospheric constituent which affect ozone. The polar-orbiting spacecraft will be placed into a 3pm-3 am Sun-synchronous orbit. The atmospheric measurements will scan the Earth's limb and measure: (1) the mesospheric and stratospheric ozone density distribution by inversion of Rayleigh-scattered ultraviolet limb radiance, and the thermal emission from ozone at 9.6 m; (2) the water vapor density distribution by inversion of thermal emission at 6.3 m; (3) the ozone photolysis rate by inversion of the O2(1g) 1.27 m limb radiance; (4) the temperature profile by a combination of narrow-band and wide-band measurements of the 15 m thermal emission by CO2; and, (5) theNO2 density distribution by inversion of Rayleighscattered limb radiance at 0.439 m. The solar ultraviolet monitor will measure both the 0.2–0.31 m spectral region and the Lyman-alpha (0.1216 m) contribution to the solar irradiance. This combination of measurements will provide a rigorous test of the photochemical equilibrium theory of the mesospheric oxygen-hydrogen system, will determine what changes occur in the ozone distribution as a result of changes in the incoming solar radiation, and will detect changes that may occur as a result of meteorological disturbances.  相似文献   
62.
63.
A general technique for calculating the sensitivities, uncertainties and overall imprecision of a model to a set of input parameters is described and applied to the calculation of CFM induced stratospheric ozone depletion. The input data set used is reaction rates and the technique highlights those that most need further study in the laboratory. The convolution of individual uncertainties to obtain an overall imprecision gives good agreement with the results of Monte-Carlo calculations using the same model.A paper presented at the IAGA/IAMAP Joint Assembly at Seattle, Washington, USA. 22 August–3 September 1977.  相似文献   
64.
A spectroscopic method for optical remote sensing of total ozone (O3) is described. It involves detailed spectral matching of near ultraviolet solar observations with synthetic profiles containing various amounts of ozone absorption. Application of this technique is made to airborne solar measurements in the 3100 to 3600 Å wavelength region. In the 3100 to 3200 Å region, measurements made above the tropopause (around geographic latitude 36.7°N, longitude 121.7°W at 0045 UT on 1/23/74) generally fit synthetic profiles constructed with 0.3 atm cm of O3 absorption andBroadfoot's (1972) extra-terrestrial solar irradiance values. However, there are several sections of the solar spectra where the observed intensity is either significantly higher or lower than the calculated value. In addition, several maxima and minima in the observed spectra do not coincide in wavelength with corresponding features in the synthetic profile. Such problems also appear when comparison is made with synthetic profiles based onArvesen et al.'s (1969) extra-terrestrial solar irradiance measurements. These discrepancies may arise from a combination of sources, including errors in laboratory measured O3 absorption coefficients, the extra-terrestrial solar irradiance values and the presence of other UV absorbing species in the stratosphere.  相似文献   
65.
The utilization of porous membranes in mass transfer processes of gaseous ozone to water was investigated. With this approach a direct control of the interface between gas and liquid is possible. Furthermore it prevents foam formation in the presence of surfactant pollution, which constitutes a problem in conventional ozonation methods. Different organic and inorganic membrane materials and geometrical arrangements were utilized and ozone transfer under varied experimental conditions was determined. Typical transfer rates obtained in the experiments were 10 g ozone per membrane square meter and hour, but under optimized conditions higher values were possible. A theoretical model was successfully applied to the results obtained. A peculiarity of the method is its inherent ozone dose control in relation to the volume flow of water.  相似文献   
66.
国产臭氧探空仪观测数据质量分析   总被引:2,自引:1,他引:2       下载免费PDF全文
对国产臭氧探空仪从2001年4月到2004年9月在北京观测的臭氧垂直分布数据的质量进行分析。对国产臭氧探空仪系统基本测量数据(包括电化学反应池池温、臭氧最大分压及其所在的高度、对流层顶的温度和高度)进行初步分析, 结果发现国产臭氧探空仪的稳定性仍需进一步提高。与地面多谱森臭氧总量观测相比, 国产臭氧探空积分的总量普遍要高,2002年至2003年之间的差别范围基本上保持在±20%以内。与国际普遍使用的双池型电化学(ECC型)臭氧探空观测结果相比, 国产臭氧探空观测臭氧分压在15 km以下、25~30km两个高度范围, 均要高于ECC测值。分析结果建议国产臭氧探空仪应尽快参与由全球大气本底监测(GAW)技术主持的世界臭氧探空仪标定中心进行标定, 并在现有的技术条件下, 向双池型电化学型臭氧探空仪这一方向发展  相似文献   
67.
OzoneVerticalProfileCharacteristicsoverQinghaiPlateauMeasuredbyElectrochemicalConcentrationCelOzonesondes①LiuQijun(刘奇俊),Zheng...  相似文献   
68.
This is a study of ozone profile shapes in the 800 to 100 millibar range obtained with balloonsonde data over Trivandrum (8.5° N) during 1975–76 and possible associations of these shapes to some meteorological parameters.Whereas monotonic ozone profiles were noted with clear weather conditions, those associated with cloud cover show three basic anomalous features. Some bulges of increased values are observed in the range of 800 to 500 mb. In the 500–100 mb range, short range or localized cloud cover or passing weather disturbances are associated with fluctuation patterns in the ozone profile and an average depleted value of ozone. The fluctuations are also associated with changing wind speed and direction at these heights.Possible causative mechanisms are discussed. Lightning associated with thundestorm, producing additional CO and NO are sought to interpret the bulges at lower heights. The decrease in values as well as the fluctuation patterns are suggested as due to possible incursion of water vapour from troposphere to stratosphere in the tropical region and dynamical effects associated with it.  相似文献   
69.
O3浓度增加对油菜影响的诊断试验研究   总被引:16,自引:0,他引:16       下载免费PDF全文
利用OTC-1型农田开顶式气室对油菜进行了不同臭氧浓度200×10-9、100×10-9、50×10-9、未过滤(25×10-9~40×10-9)和过滤掉自然大气的O3后(约为10×10-9)5个处理的长期接触试验,结果表明:目前大气本底(25×10-9~40×10-9)和50×10-9的低浓度臭氧对油菜有慢性伤害作用。臭氧浓度增加到100×10-9、200×10-9时油菜出现退绿、失水等急性伤害症状。臭氧浓度增加可导致植株矮化,株型缩小,叶片数和叶面积减少,光合速率、生物产量和经济产量下降。试验还表明,正常生长的油菜移入浓度为100×10-9、200×10-9的臭氧环境下,首先受影响的是叶肉和表皮,而此环境下的新生叶片其叶脉将首先扭曲变形。  相似文献   
70.
全球平流层-对流层之间臭氧通量的时空演变研究   总被引:15,自引:5,他引:10       下载免费PDF全文
利用1958~2001年的臭氧混合比和ECMWF(European Centre for Medium_range Weather Forecast)资料,采用Wei诊断模型定量计算了穿越全球对流层顶的臭氧质量通量.结果表明:(1)臭氧通量场存在纬向型和经向型的空间波列结构,这些空间波列均未能跨越对流层顶断裂带到达热带对流层顶控制区,其中南北两极的极区、地中海-伊朗高原-青藏高原-日本南部-北太平洋和南半球对流层顶断裂带中沿纬圈完整的空间波列最为显著.海洋上空臭氧通量的性质较为均匀一致,大陆上空的空间结构多变.北半球向下与向上的局地平均最大臭氧通量分别是-4μg.m-2.s-1和2.5μg.m-2.s-1,南半球的对应值为-2.5μg.m-2.s-1和1.5μg.m-2.s-1.(2)纬向平均的臭氧净通量依赖于纬度变化,北半球与南半球具有显著的非对称特性,总效应是平流层臭氧向对流层输运注入.臭氧通量有着显著的季节变化,可随不同季节在地理分布上发生空间转移现象,而且其控制机制不仅受对流层顶的季节运动影响,也随大气环境的季节调整而发生改变.(3)南北半球臭氧净通量的变化趋势相反,南半球为双峰结构,表现为非对称振幅的季节波动结构.全球臭氧通量振幅的年际变化表现出明显的QBO(Quasi_Biennial Oscillation)特性,年代际演变的结构形态(向下的臭氧净通量)可划分为4个阶段:1960年代是平稳变化期,1970年代为增强期,1980年代是又一个相对平稳期,1990年代为剧烈变化期.向下的臭氧净通量主极大值出现在1977、1990年和1998年,极小值在1993年和1996年.  相似文献   
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