ORIGINAL: kickin_buck
It is indeed harder for a deer (or any other animal) to detectyour odor as it gets cold. I am not saying that they cannot, just that it is harder to do so. Odor molecules are just like everything else in the world, they contract when cooled and expanded when heated.
I have no idea how much of a difference it makes, I just know it does make a difference.
I remember judging a trial once when it was bitterly cold and a dry cold to boot. We had trouble finding dogs that could follow a scent. I think a few of the more experienced dogs sight ran tracks part of the time. I do agree scent retention & strength changes with several variables.
Dan