Fig. 2. There is substantial variation in the amount of UVR reflected by different surfaces. The extremely high reflectivity of snow and ice accounts for the risk of snow blindness (photokeratitis) encountered during spring skiing at high altitudes. (Javitt JC, Taylor HR: Focal Points: Clinical Modules for Ophthalmologists 9(3). Reprinted with permission from the American Academy of Ophthalmology, 1991)