Daytime and night-time patterns in PM2.5 concentrations over Palembang City of Indonesia using MERRA-2 reanalysis data.

Palembang has sustained heavy haze pollution events that are related to decrease public health quality. Because ground-based PM_2.5 observation in the city has some limitations, such as spatial and temporal coverages. Thus, in this study, we applied the potential of using the surface mass concentration PM_2.5 data acquired by the MERRA-2 satellite to predict daytime and night-time PM_2.5 levels during heavy haze events in Palembang City. Results of the study revealed that the highest PM_2.5 level was about 160 µg/m³ at 02:00 (night-time), while the lowest PM_2.5 level was about 50 µg/m³ at 14:00 (daytime). Spatiotemporal variation of PM_2.5 over the study area showed that more than half of the area showed PM_2.5 above 90 µg/m³ at night. Stable wind conditions (2 m/s) and air temperature (29°C), and relative humidity (74%) in the study area have contributed to particulate matter accumulation. The study concluded that PM_2.5 acquired by the MERRA-2 satellite could provide a new reliable source for assessing severe air pollution events. [ABSTRACT FROM AUTHOR]