Spatial variation, sources, and trajectory of black carbon in the South Sumatra Region of Indonesia using MERRA-2 reanalysis data

Abstract

A high temperature and lack of rainfall in the South Sumatra Region during the dry season of 2019 led to an increase in intense land fires that were attributed to biomass burning and the pyrogenic combustion process. This study tried to analyze the spatiotemporal distributions of atmospheric BC (black carbon) over the South Sumatra Region during 2016–2019 land fire events using the MERRA-2 satellite images. The spatial analysis was applied to estimate the increment in black carbon concentrations during land fire episodes. Some meteorological conditions that affect black carbon diffusion and transport over the study area are explained using a backward trajectory analysis. The results exhibited that the black carbon masses mostly came from local and long-range transports (from eastern to western) over the study area. A significant percentage increment of black carbon concentration during 2016–2019 was observed at around 139%. The highest black carbon concentration recorded in October 2019 was 3.96 × 10⁻⁶ kg/m², as hotspots were still abundant, especially on the eastern side of the study area. The black carbon trend was strongly related to total hotspots and burned areas. As a whole, this finding could be beneficial for mitigating black carbon pollution due to land fires by implementing geospatial technology for rapid monitoring of air pollution in vast areas.