Limb scatter ozone retrieval from 10 to 60 km using a multiplicative algebraic reconstruction technique

摘要

The OSIRIS instrument onboard the Odin spacecraft routinely measuresvertical profiles of spectrally dispersed, limb scattered sunlightfrom the upper troposphere into the lower mesosphere. Thesemeasurements are used to retrieve the ozone number density verticalprofile using the SaskMART Multiplicative Algebraic ReconstructionTechnique, which is a one dimensional modification of an existingtwo-dimensional tomographic retrieval algorithm. The retrievedprofile extends from the cloud top to 60 km. In the absence ofclouds the retrieval extends down to 10 km. This technique allowsfor the consistent merging of the absorption information fromradiance measurements at wavelengths in the Chappuis and theHartley-Huggins bands at each iteration of the inversion. Theeffectiveness of the retrieval is demonstrated using a set ofcoincident SAGE II occultation measurements that show a mean bias ofless than 2% from 18 to 53 km.