基于N2 LBH带的中高层大气氧分子柱密度反演

摘要

In this paper,a new method for retrieving of molecular oxygen column density of the middle and upper atmosphere is presented from nadir measured data.From the cross section of absorption for oxygen molecules,we can know that the absorp-tion of molecular oxygen in N2Lyman-Birge-Hopfield short(LBHS)is strong but it is weak in N2Lyman-Birge-Hopfield long (LBHL).Based on this characteristic,we propose that the nadir radiation intensity ratio of LBHSto LBHL,ln(LBHS/LBHL) can be used to retrieve molecular oxygen column density of the middle and upper atmosphere.An interpolation table for estima-ting the molecular oxygen column density is calculated from the airglow model.This table includes ln(LBHS/LBHL)for differ-ent oxygen contents,different solar zenith angles,satellite observation angles and solar activity conditions.Then,we get the molecular oxygen column density from ln(LBHS/LBHL)and the corresponding solar zenith angle,satellite observation angle and solar activity index.Finally,we use mode simulation to evaluate the inversion result,which proves that this new method can successfully obtain molecular oxygen column density of the middle and upper atmosphere.%给出了一种利用气辉探测反演中高层大气氧分子柱密度的新方法.氧分子对 N2Lyman-Birge-Hopfield(LBH)短波带(LBHS)的吸收作用较强,而对 N2LBH长波带(LBHL)的吸收作用较弱,根据这一特性,利用N2LBHS与N2LBHL的比值来反演中高层大气氧分子柱密度.通过气辉模型计算得到一个用于估计氧气含量的插值表,计算得到在不同氧分子柱密度、不同太阳天顶角、卫星观测角和太阳活动条件下的N2LBH长短波带比值的自然对数ln(LBHS/LBHL),根据探测的ln(LBHS/LBHL)及相应的太阳天顶角、卫星观测角和太阳活动指数,拟合得到氧分子柱密度.最后,采用模式模拟的方法对反演结果进行验证,所得反演结果与模拟真值的误差在百分之十以内,证明了这种探测中高层大气氧分子柱密度新途径的可行性.