The absorption and scattering coefficients of aerosol were measured by aethalometer, nephelometer and visibility meter from February to March, 2017 in Guilin. The extinction characteristics of aerosol and gas were studies and their contributions to extinction were evaluated. The results indicated that the scattering coefficient (σsp)of aerosol in Guilin ranged from 4.64 Mm-1~1 264.41 Mm-1 with a mean value of 220.52 Mm-1, 〖JP2〗while the absorption coefficient(σap)ranged from 3.66 Mm-1~120.86 Mm-1 with a mean value of 20.05 Mm-1. Aerosol, scattering and absorption coefficients of gas, all had significant diurnal variation, i.e., double peak and double valley, this was due to the〖JP〗 driving time of tourism buses which accounted for a large proportion of motor vehicles in Guilin. The extinction coefficient of aerosol accounted for 92.65% of atmosphere extinction coefficient, in which scattering and absorption coefficients accounted for 83.54% and 9.11%, respectively. Gas extinction coefficient accounted for 7.35%. |