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排序方式: 共有253条查询结果,搜索用时 46 毫秒
61.
62.
M. Beekmann G. Ancellet G. Mégie H. G. J. Smit D. Kley 《Journal of Atmospheric Chemistry》1994,19(3):259-288
An intercomparison campaign was conducted at the Observatoire de Haute Provence (OHP) in Southern France in September 1989 in order to compare the three instruments used for vertical tropospheric ozone profiling in the European TOR (Tropospheric Ozone Research Project) network: balloon borne ECC and Brewer-Mast sondes and a ground based UV-DIAL (DifferentialAbsorptionLidar). Additionally, a stratospheric lidar system and the Dobson spectrophotometer of the OHP were operated. Seven simultaneously measured vertical ozone profiles gave evidence for systematic differences of 15% between both types of electrochemical sondes in the troposphere, the Brewer-Mast sondes reading the smaller ozone values. These differences might be explained on the one hand by a possible contamination of the ozone sensor with reducing substances, causing a negative bias mainly for Brewer-Mast sondes and, on the other hand, by the evolution of the sonde background current during the flight, causing a positive bias for ECC sondes and a negative bias for Brewer-Mast sondes. The tropospheric lidar system, measuring the vertical ozone distribution between 6 and 12–15 km, showed ozone concentrations intermediate between the sonde results. This is in good agreement with its estimated systematic error of better than 7% in the upper troposphere. In the stratosphere, the differences between electrochemical sondes and the lidar are between 5 and 10% before the normalisation with the total ozone values measured by the Dobson spectrophotometer, and always below 5% after. While the Dobson normalisation thus corrects rather well the stratospheric part of the sonde profile, it only partially reduces errors occurring in the troposphere. 相似文献
63.
全球大气臭氧层的主要特征和变化趋势 总被引:8,自引:1,他引:8
根据全球臭氧地面站(Dobson站、Brewer站、M83和M124al)总量资料、臭氧探空廓线资料和雨云卫星(TOMS、SAGEⅠfoSAGEⅡ)臭氧总量和廓线资料,给出南、北半球特别是南极地区平流层臭氧主要特征和变化趋势。结果表明,无论是中、低纬地区还是高纬地区(特别是南极地区的“臭氧洞”)臭氧总工从70年代开始呈下降趋势,特别是近十几年来有加剧下降之势,这是各国政府和科学家极为关注的环境和气候问题。此外,还对臭氧总量变化趋势的各种解释作了综述。 相似文献
64.
Gary E. Thomas Charles A. Barth Elaine R. Hansen Charles W. Hord George M. Lawrence George H. Mount Gary J. Rottman David W. Rusch A. Ian Stewart Ronald J. Thomas Julius London Paul L. Bailey Paul J. Crutzen Robert E. Dickinson John C. Gille Shaw C. Liu John F. Noxon Crofton B. Farmer 《Pure and Applied Geophysics》1980,118(1):591-615
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
65.
66.
Dixon M. Butler 《Pure and Applied Geophysics》1978,117(3):430-435
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
67.
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
68.
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
69.
Observations from aircraft, an island station, and tworesearch vessels are used to investigate the development of an elevated mixed layeror land plume over the Arabian sea during the Indian Ocean Experiment Intensive FieldPhase 1999 (INDOEX) through air mass modification. Much of the transport of aerosolsand gases occurs in this plume located above a well-mixed convective marine boundary layerwith a depth of 800–1000 m. The depth of the land plume isapproximately 2000 m with the peak ozone concentrations occurring near the centre of this land plume.Significant latitudinal variations in the concentration of ozone occur in the marineboundary layer and in the plume. Mean ozone concentrations in the land plume decreasedwith distance from the Indian coastline. 相似文献
70.
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