Vehicle fuel economy standards do in fact help reduce emissions and combat global warming. If all auto makers follow the rules the earth would be a nicer less polluted place to live. The auto industry needs to be regulated more since it is evident in big cities like L.A and NY the emmisions are way too high.
If people have to pay more for their fuel then I think they will be more conservative with how they use it which could result in them using it a lot less than they would if they did not have to pay more. It makes sense to believe that if people burn less fuel, global warming could slow down.
Increased fuel efficiency standards do not necessarily reduce carbon emissions or combat global warming. The manufacturing process for hybrid and other high efficiency vehicles entails a significant amount of additional carbon emissions in the manufacturing and assembly processes, offsetting the reductions gained by using less gasoline in those types of vehicles.