MINI MAX-DOAS MEASUREMENTS OF AIR POLLUTANTS OVER CHINA

摘要

This study continues the work of Clémer et al., (2010)rnand is aimed to improve trace gas retrievals with minirnMAX-DOAS measurements in Nanjing. Based on thatrnwork, aerosol extinction vertical profiles are retrievedrnusing the bePRO inversion algorithm developed by thernRoyal Belgian Institute for Space Aeronomy (BIRAIASB).rnAfterwards, the tropospheric trace gas verticalrnprofiles and vertical column densities (VCDs) are retrievedrnby applying the optimal estimation method tornthe O_4 MAX-DOAS measurements. The Profiles forrnNO_2, SO_2, glyoxal, formaldehyde and nitrous acid arernobtained with different results and different settings forrnthe DOAS measurement. The AODs show small positiverncorrelation against the AERONET values. For NO_2,rnthe retrieval shows reasonable concentrations in winterrnas opposed to summer and has small positive correlationsrnwith GOME-2 data. The SO_2 VCDs are not correlatedrnwith the GOME-2 data, due to high uncertainties fromrnMAX-DOAS and satellite retrievals, while the verticalrnmixing ratios (VMR) show good agreement with in-siturndata (SORPES) at Nanjing. Nitrous acid shows a maximumrnin winter and a minimum in summer, while glyoxalrnhas its maximum in August and September.