Explainer distinguishes UV sunburn risk from perceived warmth of sunlight

A science explainer argues that the warmth felt from sunlight is not a useful gauge of sunburn risk, since heat and UV damage come from different wavelengths acting through different mechanisms. Visible and infrared light warm the skin by exciting molecular vibrations, while UV-B (and some UV-A) causes sunburn by directly damaging DNA, a process that is painless as it happens. The piece notes UV-B is far less intense at ground level than near-infrared light, meaning far less energy is needed to damage DNA than to produce the sensation of heat.