The smallest ozone hole in September 2017
According to the Copernicus Atmospheric Service, at the end of September the ozone hole area was smaller than in previous years as it was monitored by satellite and numerical models and is often attributed to its low volume because the polar vortex that is associated with higher temperatures is less stable Where the ozone hole occurs over Antarctica every September-September. The rapid loss of ozone is due to the halogenated chemical species that accumulated on the polar polar clouds in the polar vortex during Antarctica winter (June-August), where it is formed only In the coldest part When the sun begins to heat the polar vortex at the beginning of spring, where the polar clouds and halogen types, such as chlorine and bromine, are released and then released, these chemical reactions begin to drain the ozone in a very efficient way. Ozone loss occurs initially on the edge Whirlpool Because these parts receive the first exposure to the sun after the polar night during this process, the polar vortex becomes warmer and thus weaker. Ozone-rich air gradually mixes outward. This begins by closing the ozone hole in a process normally completed by mid-December. Halogenated chemicals that cause ozone depletion from long-term chemicals, such as chlorofluorocarbons (SFCs). Since the reduced ozone layer means that the most harmful ultraviolet radiation from the sun reaches the Earth's surface, the Montreal Protocol was signed 30 years ago to control the production of CFCs. Although there is a ban on the emission of many of these compounds, they remain in the atmosphere because of their long life span of up to 100 years. The size of the ozone hole is controlled by changing weather conditions as well as the slow decline of ozone-depleting substances. The effects of the Montreal Protocol are supposed to have begun a decade ago. Researchers have observed the first signs of ozone-layer recovery. Typical projections (based on values ??dating back to the late 1970s) suggest that the total closure of the ozone hole will occur around the middle of this century.