Study of a high SO2 event observed over an urban site in western India |
| |
| Authors: | Chinmay Mallik S Venkataramani Shyam Lal |
| |
| Institution: | 1. Physical Research Laboratory, Space and Atmospheric Sciences Division, Navrangpura, Ahmedabad, India
2. Physical Research Laboratory, Space and Atmospheric Sciences Division, Navrangpura, Ahmedabad, 380009, India
|
| |
| Abstract: | Continuous measurements of SO2, NOx and O3 along with sampling based measurements of CO, CH4, NMHCs and CO2 were carried out during May, 2010 at Ahmedabad. The diurnal variations of SO2 in ambient air exhibited elevated values during the night and lower levels during the sunlit hours. The mean concentration of SO2 during the study period was 0.95 ± 0.88 ppbv. However, the ambient SO2 exceeded 17 ppbv in the night of 20 May, 2010. On the same day, tropospheric columnar SO2 from OMI showed almost 350% increase corroborating the surface observations over an extended height regime. This was also the highest columnar value of SO2 during the summer of 2010. Columnar loadings were also found to be high for formaldehyde, precipitable water vapor and aerosol optical depth on 20 May. Elevated concentrations were also recorded for other trace gases like NO2 and O3. Analysis of related data of trace gases indicated characteristics of fresh emissions with dominant contributions from mobile sources during the study period. However, SO2/NO2 ratio of 0.36 during the event period on 20th May connotes non-local influences. Analyses of meteorological parameters suggest combined impacts of transport and inversion causing higher levels of SO2 and other pollutants during 20?C21 May. Episodes of such enhancements may perturb chemical and radiative balance of the atmosphere. |
| |
| Keywords: | |
| 本文献已被 SpringerLink 等数据库收录！ |
|
