Quote Originally Posted by HBrown View Post
On the whole, the balance is probably tilted toward cooling. The year after Penetubo (sp?) erupted was a cold and wet one for much of the northern hemisphere. The year after Krakatoa erupted was known as the year with not summer, with snowfall recorded in the summer in many paces int he United States. A prolonged period of eruptions by multiple volcanoes may allow greenhouse gasses to build up to a greater extent than these isolated eruptions did, but the amount of particulates would be correspondingly greater as well.

Wee small correction here. Krakatoa was in 1883. The "Year Without a Summer" was courtesy of Mount Tambora. The volcanic erruption was in April, 1815,and the YWAS was 1816.