The Antarctic ozone hole has swelled this month to one of its biggest sizes on record, United Nations and USA scientists say, insisting that the Earth-shielding ozone layer remains on track to long-term recovery but residents of the southern hemisphere should be on watch for high UV levels in the weeks ahead. Continued exposure to UV rays has been known to cause premature skin aging, eye damage, weakening of the immune system, and even cancer, reports the United States Environmental Protection Agency. The ozone hole could also be reducing the Southern Ocean’s ability to stash carbon. Full recovery of the ozone layer should occur by around 2070, according to the WMO.
Advertisement
“It’s the increase in ozone-depleting chemicals in the atmosphere and a very special cold conditions that occur in winter and spring over Antarctica which provide a special, if you like, catalytic ozone destruction vessel that allows the ozone to be rapidly deployed by the higher concentrations of chlorofluorocarbons – ozone-depleting chemicals that have occurred in the stratosphere due to human activity”.
The ozone layer is part of the stratosphere surrounding the earth.
At a whopping 28.2 million square kilometres this makes it the fourth largest measured since 1991 – raising concerns as the ozone layer keeps the sun’s potentially deadly rays in check. As a result of the broad compliance with the Protocol and industrys development of ozone-friendly substitutes for the now-controlled chemicals, the total global accumulation of Ozone Depleting Substances (ODSs) has slowed and begun to decrease. “But there is no reason for undue alarm”, WMO Atmospheric and Environment Research Division senior scientist Geir Braathen said in a statement.
Ozone layer sits at around 9.3 to 18.6 miles (15 to 30 kilometers) above Earth. The layer blocks the harmful ultraviolet B radiation from the Sunday. Unusually cold temperature and weak dynamics in the Antarctic stratosphere this year resulted in this larger ozone hole. Each springtime over the last now almost 35 years, there’s been a depletion of stratospheric ozone over Antarctica primarily due to two really important factors.
Detected in the 1980s, the hole was so alarming that the worldwide community quickly agreed to ban the release of such chemicals, which were found in refrigerants and fire suppressants.
The ban has seen the hole steadily shrink, though it is not expected to fully recover until 2070. Chlorine amounts are estimated using NOAA and NASA ground measurements and observations from the Microwave Limb Sounder aboard NASAs Aura satellite.
Advertisement
End of NASA news release.
