Estimation of greenhouse gas emissions from road traffic: A case study in Korea

Transport sector is one of the largest greenhouse gas (GHG) emitters worldwide. The majority of GHGs released from this sector is mainly attributed to road vehicles that consume lots of carbon-based fuels every day. The purpose of this study is to estimate the amount of three representative GHGs (CO2, CH4, and N2O) generated by vehicles on major roads in Korea. The Tier 3 method of the Intergovernmental Panel on Climatic Change (IPCC) guidelines has been modified to propose a new simplified estimation model suitable for traffic data available in the country. Three sets of traffic data (Statistical Yearbook of Road Traffic Volume, Statistical Information for Traffic Volume in Highway, and Vehicle Detection System) that cover highways, national roads and local roads have been selected and analyzed to provide activity data for the model. With the suggested methodology yearly GHG emissions have been predicted for the years 2007 and 2008 using both the 2001 and 2005 emission factors suggested by the National Institute of Environmental Research (NIER). Results revealed that most of GHG emissions came from traffic on highways although they are much shorter than national and local roads. It might be due to the several facts that vehicles on highways run at high speeds, and traffic volumes are relatively heavier, and large percentage of trucks has big emission factors.