The UV Index is a measure of how safe it is to be out in the sun. Too much exposure to ultraviolet radiation can cause sunburn and repeated long exposure over time may lead to skin cancer and cataracts of the eyes. This video shows monthly average UV indices calculated from the UV radiation received on the Earth's surface plus the sensitivity of human skin to that light. The UV Index is forecast daily by the National Weather Service and posted by local weather channels.
Science On a Sphere
