This is the problem with your argument. You will never admit that anything can effect the temperature of the earth other than the things man is doing. The idea that a massive volcanic eruption that puts that much water vapor in the air isnt affecting global temperatures in the short term, is silly and you not admitting it makes your argument that man is causing the temp change (and we probably are to some degree) weaker. Climate is wildly complex system that is effected by all kinds of inputs (including massive volcanic eruptions) acting like that's not real is just dumb.