the sun will bounce off the snow

You may want to consider the purchase of polarized sunglasses a good sun glare extra protection. You don't need to spend the earth, although a large number of designer sunglasses will protect you, may not be expensive, do you think.
This is not only in the summer, you need to worry about the sun, but in the winter, you also need to consider what you were actually doing, and when you wear them. For example, if you are a ski or snowboard, you need to make sure that your ski goggles, fully protect your glare from the sun will bounce off the snow. However, if there is danger of ice such, polarized sunglasses may cause problems, because in some cases, the definition will be lost, because of the lack of reflection landscape like you. If there is no snow, but the condition is light, you will get the 'bounce' effect, from the wet surface. One example will benefit from the polarizing sunglasses are fishermen, because that will make it easier for them to more clearly see the sun reflecting water did not enter in their eyes. Therefore, it is important to remember, safety, rather than fashion should be your top priority.
Initially by the Edwin land development in 1936, the lens is coated with a protective substances (more common), or have a filter contained in them. Polarized absorption of solar glare reflecting surface reaches 99%, offset by the bright dazzling, restricted singular direction light eyes. For example, Oakley Sunglasses web access, you will see, their technology, so that it is now more than 99% protection lens coating forming, optimization of polarization at the molecular level.
Because there are many copies around, to test whether it is polarized sunglasses authentic, rotating them, to see if the light intensity changes, through the lens - it should not. Don't go cheap imitation, this is we are talking about you.