Some ecology? (Especially Post-Nuke)

[Dorikus]

I wanted to see some effects of the nuke bombing, like it was in Civ4. Hotter planet, something else. And then i thought - may be it can be expanded? Chopping wood will increase area of deserts, may be some woods will grow itself. It can work for separate continents or for all world. Is it possible?

P.S. Sorry for my English.