摘要
选用SBDART模式作为大气辐射传输计算模式,通过模拟计算和结果分析探讨无云的晴天、垂直对天顶观测的紫外前向散射反演大气臭氧总量的可行性．计算表明,穿透能力与探测灵敏度之间的复杂联系使得探测波长应随着sΩ_0的增大而波长变长,若用波长对探测,则波长对中较短的波长也应随着sΩ_0的增大而增大．另外大气的臭氧总量越少,反演结果受下垫面反照率、气压和仪器精度的影响越大,因而反演误差越大．当强度I_i的测量精度为±1%时,下垫面反照率R和气压P_0的分辨率分别达到±0．05和±50hPa,若用单波长探测,则在大气臭氧总量Ω_0和s都较小时,反演结果大于5%；若选用波长对进行探测,由于R和P_0的误差对反演结果的影响降低,故精度大大提高．I_i,R和P_0在上述精度下,选取适当的波长对进行探测,精度至少可达±4%,当臭氧总量高于350DU时,可达±2%．
Within the limitation of SBTART model, the paper is concerned with the preliminary study of the feasibility of determining total atmospheric ozone by scattered ultraviolet radiation from the clear zenith blue sky. The calculation results indicate that the larger sΩ0 value is, the longer the wavelength used for deriving total ozone should be. In addition, Lower total ozone content value in the atmosphere would induce less accurate retrieval results than higher one. The accuracy of total ozone determination, based on measurements at a single wavelength, is not good even if the intensity is measured within aa accuracy of 1%, reflectivity within 0.05, and surface pressure within 50 hPa.Measurements on a pair of wavelengths are found to reduce the effects of reflectivity and pressure and the retrieval results are in better accuracy. Similarly the shorter wavelength between the pair of wavelengths should be longer with the larger value of SJ？o. The wavelengths λ1 = 0.308 μm, λ2 ^- 0.3125 μm, λ3 -- 0.3175 μm associate with λ4 = 0.3300 μm respectively and produce three pairs denoted by pl, p2, p3 orderly, pl is selected when sΩ0 ≤ 1.5, p2 is selected when 1.5 〈 sΩ0 ≤ 3.0, p3 is selected when sΩ0 〉 3.0. Based on the selection principle the accuracy of retrieval results is 4% at least if the intensity is measured with accuracy within 1%, reflectivity within 0.05~ and surface pressure within 50 hPa.
出处
《空间科学学报》
CAS
CSCD
北大核心
2006年第6期445-451,共7页
Chinese Journal of Space Science
基金
中国科学院空间科学与应用研究中心创新工程资助(240519S)
关键词
前向散射
臭氧总量
Forward scattered ultraviolet radiations, Total column ozone amount
