Why do we apply sunscreen?
To help protect our skin from invisible ultraviolet (UV) rays from the sun, namely UVA and UVB rays. UVS rays are short wavelength and do not reach the earth's surface.
UVB rays make up about 5-10% of the rays that reach us:
UVA rays constitute approximately 90-95% of the rays that reach the Earth:
The daily UV index forecast is a prediction of the maximum UV strength for the day, which is usually reached in the early afternoon.
*Source US EPA.