As reported by NASA scientists, the ozone hole over Antarctica compared to 1988 (when it peaked) continues to decline. This is partly because of natural climatic processes and through international cooperation in the field of nature protection.
In 1997, 197 countries have signed an international agreement — the Montreal Protocol limiting the emissions of chemical substances that have a destructive effect on the ozone layer of the Earth. As a result, by September this year, the size of the ozone hole over Antarctica has decreased to 7.6 million square miles. Compared to the previous year, it decreased by 1.3 million square miles. This is the lowest figure over the past 30 years.
According to scientists, the main factor contributing to the decrease in ozone loss, it was unusually warm weather. However, even despite such encouraging indicators, the ozone hole still large enough, which is largely due to the high content in the atmosphere chlorine and bromine that destroy the ozone layer.
For the first time about the ozone hole over Antarctica became known in 1985 as a result of the monitoring of the atmosphere, which was conducted by British scientists. It is formed annually in August and is delayed to beginning of winter. Ozone in these areas does not exceed 30 % of the norm.
According to forecasts of the UN and the world meteorological organization (WMO), the recovery of the ozone layer over Antarctica may last until 2050.
Source — NASA Earth Observatory