If you're going to be there during winter, you need to make sure that your boots are rated for -45C or lower. Even with this, you may get slightly chilly toes. Ski goggles are a good idea if you're going to be out. A good parka, with a face-protecting ruff, is a necessity. Mitts should be the good kind that will go up to your elbows. Even with this, you may need a ski mask. Prepare to dress in layers.
Miscellaneous: If you like vegetables, you may want to bring your own... when people work up here for awhile they tend to bring tonnes of groceries in boxes on the plane.