Actually that's my initial reaction, too, but I do think there might be some kind of solution. On third thought I'm sure this is not it, but...
If (and that's actually a huge IF) we were able to model the atmosphere well enough, then I think we might be able to intervene in a sane way. My own favorite fantasy solution would be large arrays of orbital mirrors rotated as needed to control the solar energy reaching the earth. Take a bit off the sides here, add some extra crops there...
Time for a joke? We could use the mirrors to FINALLY get rid of DST. And if we had that atmospheric model we could do it without the adverse side effects...