injury to bark and cambium caused by a combination of radiant energy from light. and insufficient soil moisture.
|A sunburned back that was partially protected by a bathing suit top.|
Sunburn is a form of radiation burn that affects living tissue, such as skin, that results from an overexposure to ultraviolet (UV) radiation, commonly from the sun. Common symptoms in humans and other animals include red or reddish skin that is hot to the touch, pain, general fatigue, and mild dizziness. An excess of UV radiation can be life-threatening in extreme cases. Excessive UV radiation is the leading cause of primarily non-malignant skin tumors.
Sunburn is an inflammatory response in the skin triggered by direct DNA damage by UV radiation. When the skin cells' DNA is overly damaged by UV radiation, type I cell-death is triggered and the skin is replaced.
Sun protective measures including sunscreen and sun protective clothing are widely accepted to prevent sunburn and some types of skin cancer. Special populations including children are especially susceptible to sunburn and protective measures should be used.