Survival: Above Treeline With No Sunglasses

Can't see a thing and forgot your shades at home? We've got a solution for you.

For every 1,000 vertical feet gained, UV exposure increases by five percent; and snowfields reflect 90 percent of the sun’s glare. To prevent snowblindness, always wear sunglasses. But if a fashionable marmot swipes your Ray-Bans, cut UV exposure by folding a one-foot piece of duct tape in half to cover the sticky side. Cut eye slits one-inch wide and ¼-inch tall; punch holes in the ends; and tie them with a cord.