“Improving fuel economy carries particular salience after the Trump administration announced this month that it would re-examine the progressively more stringent Obama-era fuel economy standards for vehicles in model years 2022 to 2025.
This would be a big mistake as we try to slow down the warming of our planet and meet our international commitments on climate change. The simple fact is that American drivers are a significant contributor to greenhouse gas pollution, so having a vehicle fleet that burns less fuel can have an outsize impact on total emissions.
Though the United States has just 4 percent of the world’s population, it is responsible for 14 percent of man-made greenhouse gases that end up in the atmosphere. Transportation accounts for 27 percent of those emissions. And 60 percent result from driving personal vehicles.
Over two years, the average American driver travels a distance equal to the circumference of the earth. The average new vehicle gets only about 25 miles per gallon, which corresponds to about three-quarters of a pound of greenhouse gas emissions for each mile driven. Each year in the United States, 214 million drivers (with 240 million registered vehicles) drive 2.7 trillion miles, emitting about 2.4 trillion pounds of carbon dioxide into the atmosphere, based on the current fleet average of 21.4 m.p.g.”