We need to wear dark sunglasses in snow-covered areas to prevent damage to our eyes from bright light. Normally our eyebrows cut off the glare from the sky on a bright sunny day. In snow-covered areas, however, the white snow on the ground reflects back most of the sunlight producing a glare of very high intensity. Exposure to such bright light is capable of causing snow-blindness or temporary loss of sight. The use of sunglasses cuts down the glare and helps to prevent damage to our eyes.