Photokeratitis (snow blindness) is a real thing and should be avoided at all costs. The painful eye condition caused by exposure of insufficiently protected eyes to the ultraviolet (UV) rays of sun is exspecially potent when in snowy conditions where the light bounces off the ground bombarding your eyes from all angles. If you ever find yourself in a backcountry situation where you become separated from your goggles remember this video of improvised eye protection. It may be from 1942 but the principles are timeless….Inuit have been making similar designs for over a thousand years:
