Almost one third of US GHG emissions

come from the transportation sector, making it the largest contributor of GHG emissions in the nation.

The second most polluting mode of transportation

in the US are medium and heavy-duty vehicles, representing roughly a quarter of transportation emissions. Greenhouse gas emissions from these vehicles have increased by more than 90% since 1990.

179 million metric tons

of GHG emissions were generated by commercial passenger flights departing in the US in 2019, making the US the world's largest producer of aviation emissions.