[null and void]

It's not the coldness of the winter that makes ice ages, it's whether the summer is warm/long enough to melt the winters' accumulations.

[Myrddin]

It's not the coldness of the winter that makes ice ages, it's whether the summer is warm/long enough to melt the winters' accumulations.

You have paraphrased what I said. The issue is whether there is a net accumulation after a winter/summer cycle. If the net is positive over the long term, you have an ice age.

[mlc9852]

I admit I didn't know that. Thanks. When I think of ice age I imagine a climate where it is very cold year around. I assume that would be wrong - lol.