1987年9月16日,46个国家在加拿大蒙特利尔签署了《关于消耗臭氧层物质的蒙特利尔议定书》,开始采取保护臭氧层的具体行动。联合国设立这一纪念日旨在唤起人们保护臭氧层的意识,并采取协调一致的行动以保护地球环境和人类的健康。①地球上有一层保护膜,存在于包围地球的大气中,? On September 16, 1987, 46 countries signed the Montreal Protocol on Substances that Deplete the Ozone Layer in Montreal, Canada, and started to take concrete actions to protect the ozone layer. The anniversary of the United Nations was set up to raise awareness of the ozone layer and to take concerted action to protect the Earth's environment and human health. ① There is a layer of protective film on the earth that exists in the atmosphere that surrounds the earth.