Retrieval of tropospheric NO2 by multi axis differential optical absorption spectroscopy

Abstract

A method of retrieving NO2 in troposphere based on Multi Axis Differential Optical Absorption Spectroscopy(MAX-DOAS) was introduced. The differential slant column density (dSCD) of NO2 was evaluated by Differential Optical Absorption Spectroscopy (DOAS), removing the Fraunhofer structure and Ring effect. Combining the results of different observing directions, the tropospheric NO2 differential slant column density (△SCD) was evaluated, and the air mass factor (AMF) was calculated with the radiative transfer model SCIATRAN and the tropospheric NO2 vertical column density (VCD) was retrieved. To ensure the accuracy of the results, it was compared with the results of long path differential optical absorption spectroscopy (LP-DOAS), a good accordance was shown with the correlation coefficients of 0.94027 and 0.96924.