Ecology and the Environment
A year ago, something different was said.
"The medical dictionary said the patient was getting worse and then stabilized, and now, which is quite encouraging, the patient is recovering," said Susan Solomon, a research author work on the ozone hole, but already at the beginning of 2018 we know that the ozone hole will not completely disappear.
Ozone holes are the areas of highly-developed stratospheric ozone. They have emerged since the end of the seventies above the polar part of the southern halfway, and in the mid-eighties and beyond the polar regions of the northern half (Canada, North Europe and Asia). Through the ozone hole to the Earth's surface penetrates a portion of the ultraviolet radiation that would otherwise stop the ozone layer being damaged.
The giant hole in Earth's ozone layer will not recover completely for at least half a century, but NASA scientists at the NASA have evidence that these holes still heal and reduce.
In the early 1980s, scientists found that hair sprays, refrigerants, and various other chemicals release substances that can damage ozone and ultimately destroy it. Namely, the freons (CFCs) at the end of their path into heights (because they are lighter than air) stick to ozone molecules, and sunlight releases chlorine gas. Under the influence of the chlorine of the ozone molecule, they dissolve, and then, again, ordinary oxygen molecules are formed again. This destroys the ozone layer. One molecule of freon is sufficient to destroy a lot of ozone molecules, and to make it worse, only one freon molecule survives and remains in the atmosphere for 50 to 100 years
The open ozone hole caused a kind of global alarm, and at the end of 1987, each state signed the Montreal Protocol, committing itself to reducing freon usage by as much as 50 percent. This contract is considered to be the most successful environmental protection agreement in history, and there is evidence that the results of this celebrated contract are very successful.
Using satellite data from 2005 to 2016, NASA scientists have found that the level of chlorine in the ozone layer decreases by almost 1 percent each year. This is the first time that scientists were able to measure the chemical system within the ozone hole and study the reduction of ozone depletion. This is a great news for humankind, but scientists emphasize that decades and decades are needed for the ozone hole to disappear completely.
"Freons can live from 50 to 100 years and stay in the atmosphere for a long time. So, when it comes to an ozone hole, it will decrease by 2080, but there will still be a small hole, "said Anne Douglass, co-author of the study.
The results of the study were published in a journal Geophysical Research Letters . Recall, the ozone hole was the highest in 2000 when it was about 30 million square miles wide.