Kolkata: A research team of the Indian Institute of Technology, Kharagpur have come up with new data "confirming" that the Antarctic Ozone hole is on a "healing" path, a statement issued by the institute said Friday.
Researchers of the Centre of Oceans, Rivers, Atmosphere and Law Science (CORAL) of IIT Kharagpur have collected data from 1979 to 2017, which shows though there was a loss in saturation of Ozone since 1987 over the Antarctic, the saturation of loss at 12-21 km stretch has significantly reduced over the period 2001-2017, the statement said.
While the world is debating on climate change and global warming, the findings by CORAL researchers have given environmentalists a reason to rejoice, it said.
This is the first of its kind research providing detailed long-term (over four decades) analysis of Antarctic ozone loss saturation in terms of its occurrence, timing using high-resolution ozonesondes (a ballon borne instrument that measures concentration of ozone) and satellite measurements inside the vortex (a whirling mass of fluid or air) for the said period, the statement said.
"We have observed over the past four decades the Ozone layer depletion peaked during winters each year except the warm winters of 1988 and 2002. However, our analysis shows a clear reduction in the frequency of occurrence of ozone loss saturation over the period 2001-2017 consistently throughout various datasets," Prof Jayanarayanan Kuttippurath said.
"This reveals the emergence of an important milestone in ozone recovery," he said.
Kuttippurath along with Pankaj Kumar, Prijitha J Nair and P C Pandey from the IIT Kharagpur Coral team conducted the study.
Data were collected for various altitudes from autumn to spring, over the decades, from stations across Antarctica, including measurements from the Indian station Maitri.
The reduction of ozone loss saturation in the recent years ranged from 20 per cent to 60 per cent, across the data spread.
Asked if this was going to affect the existing protocols and regulations for industrial emissions of ozone depleting substances, Kuttippurath was quoted as saying "the recovery... suggests that the Montreal Protocol has definitely saved the ozone layer and climate of the southern hemisphere."
The Montreal Protocol on Substances that deplete the ozone layer is an international treaty designed to protect the ozone layer.
Since there are already significant changes in the southern hemispheric climate owing to the Antarctic ozone loss, the recovery from loss saturation is very likely to affect that climate, Kuttippurath was quoted as saying.
As the ozone recovery process is very slow, it will take a few decades to get back to the pre-ozone hole levels, Prof P C Pandey of CORAL, who is also the founder director of the National Centre for Antarctic and Ocean Research, was quoted as saying in the statement.
