The rays that come from the sun radiate heat can damage skin and eyes.  UV-A rays has lower energy, it penetrates deep into the eye and may injure the macula, the part of the retina, responsible for sight in the center field of vision.  UV damage is also cumulative and has been linked to eye problems later in life including tumors, cataracts and macular degeneration, an eye disease which currently has no cure.  UV-B radiation is presumably more dangerous and is mainly absorbed by the cornea and lens of the eye and can damage those tissues. Both ultraviolet-A (UV-A) and UV-B induce cataract formation and are not necessary for sight. Photokeratitis, or corneal sunburn, is a result of intense exposure to UV-B.

Chicago Eye Institute

“Too much ultraviolet (UV) radiation from the sun can damage DNA in your skin cells and cause skin cancer.  In the UK almost 9 in 10 cases of melanoma, the most serious type of skin cancer, could be prevented by staying safe in the sun and avoiding sunbeds.  Getting sunburnt just once every two years can triple your risk of melanoma skin cancer, compared to never being burnt.”

Cancer Research UK