Intercomparison of Surface Measurement and Satellite Observation of Ozone and its Precursors Co No Vocs and Estimation of their Impact on Crop Yield

Abstract

Ozone (O3) is a secondary pollutant which influences air quality, climate change and atmospheric chemistry. Being secondary in origin, tropospheric ozone formation is influenced by its precursors levels and meteorological variables, therefore, the present study was undertaken to identify complex chemistry of ozone formation, role of its precursors and meteorological variables during January 2017- December 2019. During the study period, the average concentrations of surface O3, NOx and CO were 30.4 ± 19.1, 11.6 ± 10.5 and 497.2 ± 495.8 ppb, respectively. Although several studies have been conducted on ozone and its precursors (NOx, CO and VOCs), however, limited studies have reported on satellite and surface observations both. The present study is an attempt to bridge this gap. The present thesis consists of four chapters according to the four objectives proposed. The first chapter includes diurnal and seasonal variation of O3, NOx and CO and relationship of ozone with its precursor and meteorological parameters. Trend analysis of O3 and NOx during 2010-2019 was also carried out. The second chapter includes the study of aromatic hydrocarbons, their seasonal variation and their role in ozone formation. The third chapter includes intercomparison of satellite observation and surface observation of O3 and its precursors during crop-residue burning and dust events. The last chapter includes estimation of crop-yield reduction due to surface O3 using AOT40 and M7 metrics during 2010-2019 for wheat and rice crop. newline