Seasonal Variation of Atmospheric Carbon Dioxide Over Suburban Site of Pune, India

Abstract

Increase in greenhouse gases including carbon dioxide (CO2) concentrations in the atmosphere, is the responsible factor for the global warming. This increase is caused by the anthropogenic activities like combustion of petroleum products, biomass burning, etc. In recent years, measurement network of greenhouse gases has been expanded globally. In this study, we measured the CO2 and water vapor (H2O) concentrations along with wind and air temperature over suburban site of Pune, in the year of 2018-2019 comprising the four seasons : pre-monsoon (months of March, April and May (MAM)), summer monsoon (months of June, July, August and September (JJAS)), post-monsoon (months of October and November (ON)) and winter (months of December, January and February (DJF)). Using these observations, the diurnal and seasonal variations of CO2 concentrations and fluxes were analyzed. The mean CO2 concentration was observed in the range of 380.7 – 443.6 ppm. The seasonal mean of CO2 concentration was 400, 421.5, 395.4 and 384.7 ppm in pre-monsoon, monsoon, post-monsoon and winter seasons, respectively. It is found that the height of planetary boundary layer and photosynthesis process plays a major role in seasonal variation of CO2.