Snow Blindness

Winter creates a frozen playground for countless activities. From early childhood sledding down the hills at your local playground, to making snow caves, to skiing, snowshoeing, and even snowmobiling, the outdoors is the place to be if you don’t mind the cold. Winter’s beauty is found after every fresh snowfall, in the gravity defying ice columns made from cascading water, to the peacefully quiet stillness in the air. While we may look forward to news of a school cancellation, the potential to be snowed in, and impending weather, we must respect mother nature during this frigid time of year. A very real possibility during winter is a condition referred to as “snow blindness”. In this month’s blog, I want to address this condition and the ways you can prevent it from primitive to modern methods.

What exactly is “Snow Blindness?”
When the cornea is exposed to too much UV light, the cells are temporarily damaged causing a wide range of symptoms professionally known as “photokeratitis.” Snow can reflect up to 80% of UV light and this number is highest at elevation where the air is thin. Simply put, it exists when the combination of bright sun and a snow covered landscape creates too much for your eyes to process. Your body responds to the overload of light in a number of ways including simple eye pain/soreness, blurred vision, light sensitivity, and in extreme cases, temporary blindness. If you’ve ever stepped outside into a winter environment and had to squint your eyes, you have likely been exposed to the conditions that can cause snow blindness.

Prevention and Treatment
The most straightforward treatment for snow blindness is removing the patient from the environment. This sounds simple and it can be if there is no pressing issue. In an emergency, you may be forced to travel in these conditions requiring alternative measures. Snow goggles  or glacier glasses with full wrap-around protection are optimal and allow you pain free vision. Those with sensitive eyes can also use artificial lubricating tears prior to going outside. Sunglasses that block UV rays are the most common and preventative measure but there are times when glasses are left at home, lost, and broken. Treating snow blindness requires resting your eyes. Avoiding light is best done indoors and closing your eyes and keeping them closed will allow them to heal themselves with time.

Birch Bark Goggles
Looking to the indigenous tribes of the north, one can surmise snow blindness has been a problem long before modern technology. Before the creation of polarized lenses, polycarbonate materials, and a rainbow of lens colors, natives survived harsh winter snow blindness conditions with slotted goggles. Essentially like an artificial pupil, the small hole or slit doesn’t seem large enough to look through until you place it against the eye. Traditionally these were made expediently with materials like birch bark or they were made in advance carved out of hardwood. Strips of rawhide, spruce root, or other natural cordage were used as a goggle band. Goggles like these are conceptual and you aren’t constrained to using traditional materials if you need to fabricate a pair today. Modern snow goggles can be made out of a strip of cardboard, duct tape taped back on itself to prevent ripping eyebrows off, or the vinyl from the interior of your car seats if you need to abandon it. The bottom hem of your shirt can serve as the strap to tie the goggles around your head or you can fashion cord out of a ribbon of duct tape rolled into a round.

Emergency Blanket Lenses
Emergency blankets are used commonly for post-marathon reflection of body heat, in shelter building during survival courses, and for emergency vapor barriers while camping in wet conditions. These marvels of engineering are prepackaged to the size of a deck of playing cards but open to over 6 feet long and wide enough for a human body to be enveloped in. During snow blindness conditions, you won’t need to use the entire bag in addressing the problem. Depending on the make of the emergency blanket, you may be able to use it as an emergency lens. Certain blankets have thicker construction and others are thin enough to see through when placed directly against the face. In an emergency, one could cut a thin strip and tie it around their head. This strip could also be precut and staged in your equipment should the need arise.

Side Shades
There is no fair comparison for modern protection against UV light in winter alpine conditions. Full wrap-around goggles are the way to go and my preference for down-hill skiing, snowmobiling, and travel at high elevation. Glacier glasses were designed as an alternative trading off the excess weight and bulk for sunglasses with leather side shades that extended down the arms to the side of the face. The idea was to limit the amount of light entering the eye through your peripheral vision. Wiley X glasses have protected my eyes on the range and in the woods for years but even they could use some supplemental help in snow blindness conditions. It sounds crazy and you won’t win any beauty pageants but the bags from backpacking foods can be cut into triangular pieces and adhered to the side of your favorite pair of sunglasses.Worn with a hat with a brim, you have improved protection. You still need to contend with the light entering from the bottom of your eyes but tilting your head down a bit is a stop gap short-term solution.
Snow Blindness itself is not life-threatening. As previously mentioned, your eyes will heal on their own if you remove yourself from the environment. You have to be able to remove yourself from the environment and that is where the multiplying effect of snow blindness proves itself dangerous. It isn’t easy to navigate snow, ice, and slick surfaces when you can’t see. Common tasks are more difficult when you can’t take visual cues. Fun activities can quickly become life threatening if you don’t protect your eyes. Use caution in the great wintery outdoors and enjoy it before spring melts it away.