- body area/volume. The smaller you are, the easier it is to lose heat. You probably have twice the weight, but only about 30% more body area now.
- I expect you were trained to pay attention to how you dressed in the military, and paid more attention to it than when you were young.
- advancements in clothing technology.
On the other hand, chances are that military training included doing things you should avoid when out in the cold.
- body area/volume. The smaller you are, the easier it is to lose heat. You probably have twice the weight, but only about 30% more body area now.
- I expect you were trained to pay attention to how you dressed in the military, and paid more attention to it than when you were young.
- advancements in clothing technology.
On the other hand, chances are that military training included doing things you should avoid when out in the cold.