If everyone in the country cut their driving by a quarter, total U.S. emissions would fall by 5.5 percent.

Vehicles account for just over half of household CO2 emissions. Trimming driving might mean fewer grocery trips and maybe a couple days of carpooling — but it seems survivable, doesn’t it?   

Traffic stacks up on the 210 Foothill Freeway near Los Angeles as travelers head out of town for the Thanksgiving holiday. Car travel is expected to increase 11 percent from 2009 according to AAA. Kevork Djansezian/Getty Images