TV car ads in the US will tell you everything you need to know about what the immediate impact on your wallet will be. But they don't tell you what the latest Lexus or Honda might cost you at the pump in terms of mpg, or what the cost might be to the environment in terms of CO2 emissions.
It's hardly surprising when the Honda FIT for example will run at 33mpg in the US, but its EU twin will run at 53mpg. This wouldn't matter but for the fact that the Environmental Protection Agency estimates that transport contributes approximately 27% of total U.S. greenhouse gas emissions and is the fastest-growing source of emissions. In the EU, transport (excluding air and maritime) accounts for 19% of emissions.