Volcanic Ash Forecast Debate Intensifies

I would expect the ash to reflect sunlight; as the cloud spreads it might noticeably cool the earth. On the other, sulfur and other gasses could increase the greenhouse effect.

Has anyone seen an estimate of what effect the volcano will have on our climate? How about a comparison of this to a year of human-caused emissions?

(Pardon the threadjack)

As I recall the eruption of a super volcano in Sumatra about 70,000 years ago created an ice age. So maybe this is a good thing. One ice age and one global warming condition equals one back to moderate climate (in 20 years or so of course).

Somehow I really think that volcanic eruptions can do a lot more to the atmosphere than a year of human caused emissions. Now if one of the 7 super volcanoes happens to blow at the same time then I think we're really up the creek especially since all the solar generated power will probably drop considerably in output.