In the last decade, the number of ozone holes on earth has increased to five with a total area of nearly 40 million square kilometers, nearly one tenth of the area of earth's surface. If this lasts long, the sun's ultraviolet rays will devastate humans and animals.
According to the reports of foreign media, experts from the Russian Academy of Sciences have conducted researches and experiments on four excavated "dinosaur cemeteries" in the far east of Russia. They believe that the extinction of dinosaurs is closely related to the hole in the ozone layer.
In 1985, the British Antarctic Exploration Team first found a hole in the ozone layer over Antarctica, which was about the size of the United States. It shocked the whole world and the scientific community.
According to relevant information, the ozone hole had once spread over the southernmost tip of South America in October,1994. The largest hole in the ozone layer to date has emerged over the South Pole from September to December in 1998, as one monitoring report from Japanese Environment Agency said so. The hole, which can reach 27.2 million square kilometers, is the largest hole in the ozone layer in history and has the longest duration. This is enough to show that ozone in the upper atmosphere is still declining. The report also noted that the amount of ozone over Hokkaido has decreased by nearly 3.3 percent over the past decade.
Since 1999, the hole in the ozone layer over Antarctica has nearly doubled to 21 million square kilometers, larger than twice of the area of China.
The serious destruction of the ozone layer has increased the risk of skin cancer in humans. According to a survey conducted by insiders, a 1% reduction in ozone increases the number of patients of skin cancer by about 6%, who mainly suffer from melanoma. When the Freon released by the refrigerator evaporates into gas, it will harm human eyes and increase the number of cataract patients, adding 10,000 to15,000 people with blindness caused by cataract. If measures are not taken to decrease the ozone hole, there will be about 18 million cataracts by 2075. At the same time, it can weaken human immunity and increase patients with infectious diseases.
The emergence of ozone holes has resulted in the imbalance of global ecosystem. Scientists have been experimenting with reduced production and quality of agricultural products. The increased sensitivity of more than 200 crops to ultraviolet radiation has shown that nearly two-thirds of the decline in crop yields is linked to the ozone holes. The scientists also calculated that 1% reduction in ozone would mean 1% reduction in soybean production.
In addition, ozone holes have greatly reduced fishery production as well. Ultraviolet radiation can also kill single-celled marine plankton within the depth of 10 meters. And it can also destroy forests.
To anyone's surprise, the main culprit of ozone holes is the frequent use of refrigerant like chlorofluorocarbons in industry and life. It has never occurred to human beings that, while benefiting human beings, fluorochlorocarbons will also run into the sky leading to disasters and bring "the ultimate devastation" to the human world.
The sky people look up at every day is now riddled with holes, and the sum of the ozone holes has now exceeded the total area of four China.
The ozone layer can absorb the sun ultraviolet ray that is harmful to life on earth. It is the protective umbrella of all life on earth, the natural barrier that protects mankind. Without it, all life on earth would be destroyed. That is why the United Nations government has repeatedly stressed the harm of ozone destruction.
After a large amount of depletion of the ozone layer, its ability to absorb ultraviolet radiation is greatly weakened, resulting in a significant increase in the amount of ultraviolet radiation reaching the earth's surface, which brings various hazards to human health and the ecological environment. Ozone is the main component absorbing the sun's ultraviolet rays. And the most obvious harm caused by the destruction of the ozone layer is to increase the risk of skin cancer in humans when exposing them to more intense ultraviolet radiation.
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