The ultraviolet (UV) index is a forecast of the expected intensity of ultraviolet radiation from the sun at the Earth’s surface for a specific day. It’s typically presented as a number ranging from 0 to 11+, with higher numbers indicating a greater risk of harm from sun exposure. For example, a UV index of 3 to 5 suggests moderate risk, while a UV index of 8 to 10 indicates a very high risk. This value is calculated based on factors such as the sun’s angle, ozone levels in the atmosphere, and cloud cover.
Knowledge of the predicted UV radiation levels allows individuals to take appropriate protective measures, thereby minimizing the potential for sunburn, premature skin aging, and skin cancer. Public health organizations and weather services routinely provide this forecast as a tool for promoting sun safety. Historically, the development of the UV index represented a significant advancement in educating the public about the dangers of excessive sun exposure and empowering them to make informed decisions regarding outdoor activities.