an ozone hole, seven times larger than the ozone hole in Antarcticais currently over tropical regions and has been since the 1990s 1980as published by a Canadian researcher in the journal ‘AIP Advances’.
Qing-Bin Lu, a scientist at the University of Waterloo in Ontario (Canada), reveals a large ozone hole throughout the season –defined as an area of ozone loss greater than 25% compared to the undisturbed atmosphere– in the lower stratosphere over the tropics comparable in depth to that of the well-known Antarctic spring hole, but about seven times larger in area.
“The tropics constitute half of the planet’s surface and approximately half of the world’s population lives in them,” explains Lu. “The existence of the tropical ozone hole may cause great global concern“.
“The depletion of the ozone layer can cause a increased ultraviolet radiation at ground levelwhich can increase the risk of skin cancer and cataracts in humans, as well as weaken the human immune system, decrease agricultural productivity, and negatively affect aquatic organisms and sensitive ecosystems.”
More danger from radiation
Lu’s observation of the hole in the ozone layer comes as a surprise to his colleagues in the scientific community, as it was not predicted by scientists. conventional photochemical models.
Their observed data are in good agreement with the cosmic ray-driven reaction of electrons (CRE) model and strongly indicate the operation of an identical physical mechanism for Antarctic and tropical ozone holes.
As in the case of the polar hole, in the center of the tropical ozone hole is out of stock about 80% of normal value of ozone.
Preliminary reports show that ozone depletion levels over equatorial regions are already endangering large populations and that the associated UV radiation reaching these regions is much higher than expected.
In the middle of the decade 1970atmospheric research suggested that the ozone layer, which absorbs most of the sun’s ultraviolet radiation, could be depleted by industrial chemicalsmainly chlorofluorocarbons (CFCs).
The discovery in 1985 of the hole in the ozone layer antarctica confirmed ozone depletion caused by CFCs. Although the ban on these chemicals has contributed to halting the depletion of the ozone layer, evidence suggests that it persists.
Lu says that tropical and polar ozone holes play an important role in the cooling and temperature regulation stratosphere, reflecting the formation of three “temperature holes” in the global stratosphere. He adds that this finding may prove crucial to better understanding global climate change.
Related news
Lu’s discovery builds on earlier studies of the CRE-initiated ozone depletion mechanism that he and his colleagues originally proposed about two decades ago.
“The present discovery calls for further detailed studies on ozone depletionchanging UV radiation, increased cancer risk and other negative effects on health and ecosystems in tropical regions,” Lu suggests.