Incremental Concentration of Black Carbon Aerosol from Road Traffic in Inner Bangkok

Commonly referred to as soot, black carbon (BC) is a primary aerosol emitted from incomplete combustion of organic materials such as fossil fuels, biofuels and biomass. BC aerosol is a dominant anthropogenic solar radiation absorber, absorbing approximately 1 million times more radiation per unit of mass than CO2. Recent research has found that BC is the second largest anthropogenic contributor to global warming. BC aerosol is not only a short-lived climate forcer (SLCF) but also an air pollutant that adversely affects human health. Emission sources of BC aerosol are mainly residential, industrial, transportation related and/or and open burning sources. In a large city with serious traffic congestion such as Bangkok, vehicles are the most significant source of BC aerosol. The objective of this study is to determine BC concentrations in Bangkok’s ambient air caused by road traffic. BC concentrations in the center of Bangkok city were measured using an aethalometer located on the rooftop of the Department of Environmental Engineering’s five-story-building at Chulalongkorn University, Bangkok. Measurements were carried out in the dry season of January 2013, when atmospheric aerosol concentrations are high. BC concentrations were measured on a 24-hour basis for a continuous 7-day period. The result