re: #29 Walter L. Newton

Temps may be lower locally in the US, but higher in other regions. But to try and extrapolate global temps from those registered in the US and Canada is going to be misleading.

Glaciers require several factors to form - temperature and precipitation. If one or the other is lacking, glaciers will either not form, or will shrink (lack of new ice formation from compacting snow).

Regional variations could include El Nino/La Nina oscillations, which have global effect.