people living on hills often get sunburns on their skin. Which component of sunlight is responsible for this effect? Why is this effect generally not observed near sea level?

People living in the hilly areas are exposed to the strong rays of the sun because of which they get sunburns. Sunburns are normally caused due to the ultraviolet rays present in the sunlight which has the intense heating effect causing the skin to get reddened.

This effect is not generally observed near the sea regions because the sun rays are not that strong near the sea surface in technical terms the intensity of sun rays is less at sea level.