Revoking CA examption could affect air nationally for centuries

California began limiting vehicle emissions due to its smog-trapping geography. About a third of the remaining states have adopted its standards. And cars with the higher restrictions generally are available to those who live in states that border those states.

People are not likely to stop driving. So, without California's stricter standards, cars could be using more fuel for at least several decades, and the increased pollution could remain in the air for centuries.

For more, read The Atlantic analysis.