Feasibility study for joint retrieval of ozone and air density profiles in the mesosphere and upper stratosphere using an ultraviolet limb-scan technique

Abstract

Using an ultraviolet limb-scan technique, this paper carries out the feasibility study of joint retrieval of ozone and air density vertical distributions in the mesosphere and upper stratosphere. Ozone and air density profiles are important parameters for middle atmosphere circulation. Satellite observation is the major method to obtain the parameters globally. In past years, there have been many research satellites, such as SME, the Shuttle Flight STS-87, using UV and IR waveband instruments to retrieve these parameters by limb-scan technique. As UV radiances observed by the satellite contain both information of ozone content (via absorption) and air density (via Rayleigh scattering), it is feasible to retrieve simultaneously these two parameters. In this paper, based on a radiative transfer algorithm for limb-scan mode, the joint retrieval feasibility study is carried out. In this paper, the method based on the Direct Method proposed (1976, 1982) by Aruga et al. is applied to retrieve ozone and air density profiles using simulated satellite measured data of multiple ultraviolet wavelengths by limb scanning and the sensitivity tests of air density errors to ozone inversion precision are performed together. Here, a joint retrieval scheme of ozone and air density is established, which makes it possible to obtain air density profile ,as well as ozone profile with an improved accuracy in the mesosphere and upper stratosphere.