Emission Amounts of Main Pollutants from Mobile Sources

In 2020, the national emission amounts of carbon monoxide (CO), hydrocarbons (HC), nitrogen oxides (NOx), particulate matter (PM), and sulfur dioxide (SO2) from mobile sources were 8.954 million tons, 2.327 million tons, 11.045 million tons, 0.305 million tons, and 0.163 million tons, respectively. Among them, motor vehicles, construction machinery, agricultural machinery, vessels, locomotives, and aircraft account for 86.0%, 2.8%, 7.4%, 3.1%, 0.2%, and 0.5% of CO emissions, respectively. HC emissions account for 81.7%, 5.1%, 8.8%, 3.9%, 0.3%, and 0.2% from the same sources. NOx emissions account for 56.7%, 13.6%, 15.1%, 12.9%, 1.1%, and 0.6% from the respective sources. PM emissions account for 22.3%, 25.2%, 30.2%, 20.0%, 1.6%, and 0.7% from the same sources. Motor vehicles are the main source of CO, HC, and NOx emissions, and non-road mobile sources contribute significantly to NOx and PM emissions.