Comprehensive analysis of long-term trends, meteorological influences, and ozone formation sensitivity in the Jakarta Greater Area.

Jakarta Greater Area (JGA) has encountered recurrent challenges of air pollution, notably, high ozone levels. We investigate the trends of surface ozone (O) changes from the air quality monitoring stations and resolve the contribution of meteorological drivers in urban Jakarta (2010-2019) and rural Bogor sites (2017-2019) using stepwise Multi Linear Regression. During 10 years of measurement, 41% of 1-h O concentrations exceeded Indonesia' s national threshold in Jakarta. In Bogor, 0.1% surpassed the threshold during 3 years of available data records. The monthly average of maximum daily 8-h average (MDA8) O anomalies exhibited a downward trend at Jakarta sites while increasing at the rural site of Bogor. Meteorological and anthropogenic drivers contribute 30% and 70%, respectively, to the interannual O anomalies in Jakarta. Ozone formation sensitivity with satellite demonstrates that a slight decrease in NO and an increase in HCHO contributed to declining O in Jakarta with 10 years average of HCHO to NO ratio (FNR) of 3.7. Conversely, O increases in rural areas with a higher FNR of 4.4, likely due to the contribution from the natural emission of O precursors and the influence of meteorological factors that magnify the concentration.