Many factors in your home can contribute the life and longevity of your roof.  On the topic of ice dams, the stack effect has a major effect because it warms the temperature in the attic.  In addressing this issue, it is possible to eliminate the problem by treating the root of it.

The “stack effect” occurs in both the summer season and the winter season.  When warm air enters through the lower levels of the house, rises up and releases through the roof, you have a stack effect.  Essentially, as the warm air is escaping through the attic and roof space, more cool air is drawn in and the cycle continues.  The stack effect can be detrimental because when the warm air is released through your roof, it melts the snow on the roof, which in turn freezes and then backs up creating a dangerous ice dam.

It is important to address the problem of the stack effect in order to prevent any damage to your roof, not to mention the money you would save on wasted energy.  Consider conducting and efficiency test in your home to determine where the cool air is coming from, by sealing any leaks you can significantly decrease the amount of warm air rising.

Source:  http://www.basementsystems.com/crawl-space/stack-effect.html