Is sunlight poisonous?

Long-term overexposure to the sun is considered to be related to many kinds of skin cancers, which are caused by excessive ultraviolet rays in the sun or fluorescent lamps.

In order to prevent the adverse effects from mild sunburn to severe burns, sunscreen or other sunscreen agents should be used appropriately. Another harm of ultraviolet rays is that it can accelerate skin aging (also called skin photodamage), and even makeup can hardly make up for the ugly image it brings. The reduction of ozone layer in recent ten years has greatly increased the probability of the above-mentioned health disasters. So those who are exposed to strong sunlight every day should take necessary measures.

The spectral range of surface illumination depends on the influence of the atmosphere on the height of the sun. The dusk around sunrise and sunset depends on the blue spectral components dominated by atmospheric scattering, while red light dominates the color of sunrise and sunset. These effects are obvious in natural light photography, where the illumination is sunlight through the atmospheric medium in principle.