夏天,太阳最远可直射北回归线,给我国大部分地区带来炎热。包绕地球的大气外层,有一层厚厚的臭氧层,它能阻挡绝大部分的紫外线,对地球生物有保护作用。但随着工业的发展和含氟致冷剂的大量使用,臭氧层受到破坏变薄,有的地方甚至出现空洞,这就使照射到地表阳光中的紫外线大大增加。 过度的曝晒,阳光中的紫外线对人体有害,特别是对皮肤和眼睛。对皮肤,表现为受曝晒后皮肤潮红、发烫、有刺痛感,严重的会起泡脱皮,之后皮肤逐渐变黑。变 In summer, the sun can reach the tropic as far as possible to the tropic in most areas of our country. The outer layer of the atmosphere, which surrounds the Earth, has a thick layer of ozone that blocks most of the ultraviolet light and has a protective effect on the Earth’s biology. However, with the development of industry and the extensive use of fluorine-containing refrigerants, the ozone layer is damaged and thinned, and even hollow areas exist, which greatly increases the amount of ultraviolet light that shines on the surface sunlight. Excessive exposure to sunlight in the UV harmful to humans, especially on the skin and eyes. The skin, manifested as exposure to the sun after the skin flushing, hot, tingling, severe foaming peeling, then the skin gradually black. change