The hole reached a size of 26 million square kilometers on September 16, 2023. What scientists call the “ozone depletion zone” is about three times the size of Brazil, says the European Space Agency (THE).
The ozone hole is a phenomenon that occurs in the stratosphere, which is between 10 and 50 kilometers high. In this layer the ozone concentration is much lower than in the rest of the atmosphere.
Ozone is a colorless gas that forms a thin layer in the atmosphere and absorbs the harmful components of sunlight, known as “ultraviolet B” or “UV-B,” protecting people from the risk of skin cancer or cataracts, among other things to get sick.
Numerous studies have been conducted on the ozone hole over the years. These have provided information about the causes, development and consequences of this phenomenon.
climate change-ozone layer.jpg
Greenhouse gases not only damage the ozone layer, but also retain heat up to 10,000 times longer than carbon dioxide (CO2).
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Two increases
In this sense, the Master in Environmental Education and Professor of Natural Sciences mentioned the Earth Sciences at the Pedagogical Institute of Caracas, Venezuela (UPEL), Víctor Manuel Reyes DIARIO LAS AMERICAS that a distinction must be made between two increases. “The first was the increase in the ozone hole from the middle of the last century to the end of the century, which was associated with emission sources and applications of HCFCs and CFCs. “A situation that has been systematically managed since the end of the last century.”
He also emphasized that it has been shown that the ozone hole has fluctuations or annual fluctuations. “Between the months of November and July there is a greater presence of ozone, which leads to a reduction in the area called the ozone layer hole.” However, between August and October it was shown that the size of the hole depends on the behavior of the temperature in the stratosphere. “Records indicate that the hole’s maximum generally occurs between mid-September and mid-October.”
Strong wind orchestra
According to ESA, the variability in the size of the ozone hole is largely determined by the strength of a strong band of wind that flows around the Antarctic zone. This strong band of wind is a direct result of the Earth’s rotation and the large temperature differences between polar and temperate latitudes.
Reyes pointed out that “a natural climate control mechanism is at work.” When temperatures in the stratosphere in the Southern Hemisphere begin to rise during the months of high solar radiation, ozone depletion slows, the polar atmospheric circulation weakens and eventually collapses . However, in late December and early January, ozone levels increase and are considered normal,” he said.
Hunga Tonga volcano
Although it may be too early to discuss the reasons for current ozone concentrations, some researchers speculate that this year’s unusual ozone patterns may be related to the January 2022 Hunga Tonga-Hunga Ha’apai eruption, one said Communication from EuropaPress.
Antje Inness, senior scientist at CAMS, said: “The eruption of the Hunga Tonga volcano in January 2022 ejected large amounts of water vapor into the stratosphere, which only reached the south polar regions after the hole in the ozone layer disappeared. 2022.” However, they noted that the exact impact of the Hunga-Tonga eruption on the ozone hole in the Southern Hemisphere is still the subject of ongoing research, as there are no previous cases in modern observations of large amounts of water vapor being injected into the stratosphere.
“Water vapor may have led to increased formation of polar stratospheric clouds in which chlorofluorocarbons (CFCs) can react and accelerate the depletion of the ozone layer. “This could also contribute to the cooling of the Antarctic stratosphere, further increasing the formation of these polar stratospheric clumps and leading to a more robust polar vortex,” the ESA experts explained.
While Reyes explained that recently the possible influence of both wildfires and volcanic eruptions has been highlighted, “and the chemical dynamics that would arise from the incorporation of water vapor and other aerosols. The damage to ozone has also been pointed out.” Since fungicides contain methyl bromide, constant monitoring must be carried out.
Effect of substances
The specialist clarified that since the 60s of the last century, an increasing depletion of the ozone layer has been observed, “which was associated with emission sources and the use of HCFCs (chlorofluorocarbons) and CFCs (chlorofluorocarbons) in refrigeration devices,” but also in paints , aerosols and paints. “Industrial development after World War II encouraged the use of these compounds and the resulting degradation of the atmosphere.”
In the 1980s, scientists discovered that the ozone hole was growing at an alarming rate. In response, the Montreal Protocol, an international agreement banning the production and use of CFCs, was signed in 1987.
At this point, widespread use of harmful chlorofluorocarbons in products such as refrigerators and aerosol cans was damaging the ozone levels in our atmosphere and causing a hole in the ozone layer over Antarctica.
Montreal Protocol
In response, the Montreal Protocol was established in 1987 to protect the ozone layer by phasing out the production and consumption of these pollutants, leading to ozone layer recovery.
In this context, Víctor Manuel Reyes explained that the Montreal Protocol aimed at eliminating HCFCs (chlorofluorocarbons) and CFCs (chlorofluorocarbons), “which was the necessary measure at the end of the 1980s of the last century, but “which The Protocol initially saw “There are no restrictions on the use of HFCs (hydrofluorocarbons) as they have not been proven to deplete the ozone layer and are therefore outside the scope of the Treaty.”
In turn, he recalled that in 2016 an extension of the Protocol (Kigali Amendment) considered HFCs to be of anthropogenic origin due to their impact on the greenhouse effect. “This amendment stipulated that an 80% reduction in the estimated production and consumption of HFCs should be observed in the three decades following their formalization. This will force manufacturers of air conditioning and other equipment to replace these compounds with alternative refrigerants and comply with the provisions of the Montreal Protocol,” he explained.
Reduce
Claus Zehner, ESA mission director for Copernicus Sentinel-5P, points out that “due to the Montreal Protocol and the decline in anthropogenic substances that deplete the ozone layer, scientists currently predict that the global ozone layer will return to normal around 2050 .” .”
For his part, Reyes explained that although it is premature to talk about detailed forecasts for the whole year. “We certainly have arguments that indicate that there is a trend towards a reduction in the size of the ozone hole.
“There are estimates that put the decline in anthropogenic substances that have a negative impact on the ozone layer at 1% per year. “This predicts a scenario with complete elimination of HCFCs by 2030, assuming that the ozone layer could return to normal by the middle of the century,” he added.
Pollutant emission countries
The expert also explained that the Montreal Protocol was signed by 197 countries, including China, which was asked about its commitment policy to this protocol. “It was pointed out that the Asian country pursues a foreign policy of ratifying the commitment, but behind closed doors ignores the provisions of the Montreal Protocol, thus avoiding new investments to replace CFCs and HCFCs,” he stressed. .
He specified that this criticism comes despite the financial efforts of the Multilateral Fund for the Implementation of the Montreal Protocol and the United States Environmental Protection Agency “to support projects aimed at the gradual elimination of substances that deplete the ozone layer (ODS). )” .
At the same time, he stressed that another similar criticism was leveled at countries that use fungicides containing methyl bromide in their agricultural sectors, “a situation evident, for example, in the wine-producing countries of the Southern Cone.” Another criticism was leveled at oil-producing countries in the Middle East , Africa and the Americas as well as countries in Southeast Asia and the two Koreas.
Consciousness phase
In his opinion, this suggests that we are still in a phase of awareness of the problem, “and that, despite international efforts, there are still asymmetries around the world.”
Finally, the expert called for continuing to promote sustainability assessments that take into account environmental performance and metrics within countries, “but also requirements for international business operations.” From the estimates to the realization of the goals set out in the Montreal Protocol and the 2030 Agenda, we have “We still have a long way to go.”
@Lydr05
SPRING: With information from the European Space Agency (ESA) and EuropaPress