The concentration of ozone in the atmosphere is unstable - that's a fact. Climatic phenomena are increasingly influenced by humans. The ozone layer over the high latitudes of the Southern Hemisphere is thinner than the average values for the planet - it is also difficult to argue with this. The rate of cancer among Australians is higher than among residents of other territories - also an indisputable statement.
How are myths born from facts? What to believe? Let's try to figure it out.
Saving Ozone
The ozone layer in the Earth's atmosphere is only 3%. But it was thanks to him that all life on our planet got a chance to exist. This is the "armor of God" that protects us from the deadly ultraviolet radiation. The sun brings with it both life and death at the same time. Concentration is decisive here.
The ozone molecule consists of three oxygen atoms. This molecule can be formed as a result of various chemical processes. Most often in nature, this happens when an oxygen molecule is exposed to ultraviolet light. The main thing here is the wavelength. At an altitude of 15-20 km from the earth's surface, oxygen molecules in the atmosphere, under the influence of ultraviolet radiation with a certain wavelength, decay into oxygen atoms. They form ozone molecules. And already they, in turn, absorbing ultraviolet waves of a different length, turn back into oxygen. And the cycle starts again.
The ozone layer is constantly being restored. To exist, it needs oxygen and ultraviolet radiation, the concentration and intensity of which we cannot influence today.
Why is the ozone hole over Australia called that?
The content of ozone in the atmosphere is measured in Dobson units. The average value on the planet is about 300. A value below 220 units is considered critically low or abnormal. Areas of the atmosphere with such indicators are called "holes". This is a publicistic image, there is no gap in the atmosphere, of course.
The study of the ozone layer began in 1912, when it was described by Charles Fabry and Henri Buisson as part of the stratosphere. For the first time, the anomalous phenomenon, which we call the ozone hole over Australia, was discovered in 1957. Then the news went unnoticed. Nearly thirty years later, in 1985, a team of scientists led by Joe Farman published their findings on the atmosphere over the south pole. The ozone hole over Australia and Antarctica at that time had a diameter of 1,000 km and was the size of the United States. The world perceived this as an environmental threat. Over thirty years of observations, the ozone concentration did not exceed 220 Dobson units and dropped to 80 units. In the same 1985, Sherwood Rowland and Mario Molina proved the destructive effect of chlorine on ozone molecules.
And the world began to fight for the preservation of the ozone layer of the Earth, especially since the ozone hole over Australia and New Zealand was not the only one. An abnormally low ozone content was recorded in the northern and temperate latitudes of the globe. Over the Arctic, the area of the ozone hole is determined to be 15 million km2 - not much less than over Antarctica. Everything that in any way could emit chlorofluorocarbons into the atmosphere - refrigerators and aerosols - was declared an "enemy".
In 1987, the Montreal Protocol for the Protection of the Ozone Layer was signed. Over the past 30 years, emissions of harmful substances into the atmosphere have decreased by 8 times. By the end of the century, the Australian ozone hole will remain only in the memory of mankind as an example of its unreasonable attitude towards nature.
Ozone holes were, are and will be
There is an alternative point of view. Some scientists consider the existence of the ozone hole to be a natural climatic phenomenon that occurs in the atmosphere over any territory. Only in the northern and temperate latitudes does the “life” of the hole not exceed two weeks, and the ozone hole over Australia keeps a minimum of values for 3–6 months.ozone concentration.
Arguments in favor of human innocence in the appearance of ozone holes are as follows:
- The amount of artificial chlorine is negligible. Even if you break all the refrigerators, its concentration will be several times less than what is released into the atmosphere during volcanic eruptions.
- Large ozone patches are located above areas with minimal anthropogenic impact. The mass of chlorfreon molecules is very large, and there was no way they could be carried by the wind from Europe and Asia to Antarctica.
- The density and amount of stratospheric clouds over the poles is much greater than over the rest of the territories. They reduce the intensity of ultraviolet radiation and, as a result, the formation of ozone.
- The high number of oncological diseases is explained by the fact that Australia is located where the very high value of total solar radiation is geographically determined. At the same time, more than 90% of the population are descendants of immigrants from northern Europe and Great Britain, genetically not adapted to such an intensity of solar radiation. There are no statistics on oncological diseases among Australian Aboriginal people.
Competitive Wars
For the first time, the destructive influence of man on the ozone layer was discussed in the late 70s. Civil aviation supersonic aircraft were hit. Military equipment was not mentioned. Nitrogen oxides, a product of supersonic aircraft fuel combustion, were then assigned the culprit.
This is the time of formation and developmenttransatlantic civil flights. Boeing, Concorde, Tupolev Design Bureau competed for leadership in this market. The last two organizations relied on supersonic aircraft. As a result of the unfolding campaign, a number of countries passed a law banning civilian supersonic flights. Boeing has become almost a monopoly - they forgot about the ozone layer for a while.
The next wave of interest in this layer of the atmosphere was launched, as many believe, by DuPont, a manufacturer of expensive chemicals. For thirty years, cheap chlorofluorofreon has been almost everywhere replaced by expensive fluorofreon. DuPont leads the organofluorine industry by a wide margin.
Whatever point of view you hold, this whole story is useful in one thing: before you change something, you need to think about the consequences.
