Depolarization ratio of zenith scattered radiation and measured NO2 slant columns

摘要

The present paper deals with the factors influencing the accuracy of the DOAS and in particularly, with the changing of the depolarization ratio of the zenith scattered radiation and related variations of the retrieved NO$-2$/ slant column. Ground based measurements carried out during 1997 and 1998 of the polarization state of the zenith- scattered radiation and the NO$-2$/ slant columns have been obtained in 4075 angstrom - 4640 angstrom spectral interval. The depolarization ratio is calculated from the spectra registered with a sheet linear polarizer, inserted into the instrument. A linear regression analysis is applied to retrieve NO$-2$/ slant columns. The obtained results are analyzed and discussed.