Abstract
The results from 1-year of measurements of PM2.5, organic carbon (OC) and black carbon (BC) concentrations are presented for an urban traffic-influenced site, the Farm Gate in Dhaka, Bangladesh. The measurements were based on sampling using two Air Metrics simultaneously operating samplers. The concentrations of OC and BC concentrations in PM2.5 varied from 5-96 μg/m^3 and 4-48 μg/m^3, respectively. The concentrations of PM2.5 varied from 11-328 μg/m^3. The annual particulate organic matter (POM) accounted for 46 ± 11% in PM2.5 whereas BC stayed at 33 ± 12%. The effects of meteorological conditions on the variability of OC and BC concentration were examined and the contribution of secondary organic aerosol to the total OC was calculated. The concentrations of OC and BC relative to the total PM2.5 are high and have good correlation with wind speed and temperature. The OC/BC ratio correlated with wind speed, temperature and sulfur concentration. Based on these relationships, it can be concluded that both local and regional sources of OC and BC are important. The local sources are traffic, coal and biomass burning. Distant sources include areas where there is extensive agricultural burning.
Highlights
Carbonaceous species, organic carbon (OC) and black carbon (BC), constitute a major, sometimes dominant fraction of atmospheric fine particulate matter
The concentrations of OC and BC concentrations in PM2.5 varied from 5–96 μg/m3 and 4–48 μg/m3, respectively
This location is known as continuous air monitoring station (CAMS) site started from 2009 handled by Department of Environment (DoE) in Dhaka
Summary
Carbonaceous species, organic carbon (OC) and black carbon (BC), constitute a major, sometimes dominant fraction of atmospheric fine particulate matter. Black carbon is the principal light-absorbing species in the atmosphere, playing an important role in the aerosol climatic forcing (Jacobson, 2001). Black carbon is an incredibly important global warming agent because it warms the earth in two ways. It absorbs light because of its dark color and radiates heat into the atmosphere, raising air temperature. It deposits on snow and ice, darkening the light surfaces, absorbing more heat and accelerating melting (Kerwald et al, 2008). Reducing black carbon provides near-term benefits by slowing warming and ice melt. Black carbon is between 760 and 2600
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
