This belongs more on a geology forum, but since it's related to climate change and ice melting, I'm posting it here because it's interesting. Ice is heavy - in fact, ice is so heavy, geologists have predicted that many volcanic chambers underground are being kept at bay by the weight of ice sheets above them (Greenland is a perfect example). Google it. Look it up. I learned this a few months ago from the History Channel, wikipedia, and reading geology websites (via Google). Study: Greeland rose as ice melted - UPI.com
Not surprising and expected result.Interestingly there should be some downlift in coastal areas, as the weight of ice tend to push immediate surrounding areas up. This phenomenon combined with lower sea level during ice periods had put many coastal paleolithic archeological sites under the water and covered most of "great migration" coastal routes, but this is another story..
OK so global warming will cause more volcanos, which in turn cause global cooling? I hate when that happens, got stuck in Europe the last time it happened.