Sunscreen shouldn't be packed away just because it's winter. Your skin can be exposed to harmful rays all year long. So before you hit the slopes, build a snowman, or head off to a tropical beach, take time to protect yourself, say skin cancer experts at Dana-Farber Cancer Institute. According to the American Cancer Society, snow, ice and water can all reflect the ultraviolet radiation that causes sunburn. Sunburn in turn increases the risk of developing skin cancer. Some exp