A second ozone hole could also be present above the tropics: seven times larger than the well-known one above Antarctica and, unlike the latter, which sees the ozone layer thinning mainly during the spring season, present all the year.
According to research from the Canadian University of Waterloo, coordinated by Qing-Bin Lu and published in the journal of the American Institute of Physics (Aip Advances), the tropical ozone hole has been there since the 1980s and could be a source of great global concern, since the tropics make up half the planet's surface and are home to about half of the world's population.
"The depletion of the ozone layer can lead to an increase in ultraviolet radiation at ground level, which, in turn - says Lu - can increase the risk of skin cancer and cataracts, can weaken the immune system, decrease productivity. agricultural and negatively affect aquatic organisms and sensitive ecosystems ".
The results presented by the Canadian researcher come from observations regarding the ozone layer, the distribution of chlorofluorocarbons (Cfc, the chemicals used in the past as refrigerants and believed to be partly responsible for ozone loss) and the behavior of the atmosphere.
The data came as a surprise to the rest of the scientific community, as the existence of this tropical ozone hole was not predicted by conventional models.
Preliminary reports, however, show that ozone depletion levels in equatorial regions are already endangering large sections of the population and the UV radiation reaching these areas is much greater than expected.
"This discovery could be crucial for a greater understanding of global climate change - adds Lu - but further studies on the weakening of the ozone layer in the atmosphere will be needed".
