I don't think the volcanic ash is wide-spread enough to cause any kind of lasting effect to the climate. If we had worldwide volcanic eruptions, that would be another thing. But the CO2 emitted by the volcanos (if we had a worldwide eruption) would actually warm up the air because they absorb and re-emit more heat than most other gases - in fact, I'm sure you've heard about the rising levels of CO2 emissions (by fossil fuels, cars, etc) that are contributing to global warming.
Again though, one volcano isn't going to change things too much. Venus is a perfect example of a runaway greenhouse effect caused by too much CO2 in the atmosphere. More information csep10.phys.utk.edu/astr161/lect/venus/g... here.
Edit: I actually just found an interesting article huffingtonpost.com/2010/04/19/icelandic-... here that discusses the volcano's CO2 emissions, and claims that the levels are "Nothing Compared To European Aviation Industry's.
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.