New Delhi: A UN-backed scientific panel has concluded that actions taken under the Montreal Protocol have successfully strengthened Earth’s ozone layer, helping to prevent global warming from rising by 0.5 to 1 degree Celsius by the middle of the century.
The Montreal Protocol is a 1989 international treaty that aims to regulate the production and use of chemicals that contribute to the depletion of the ozone layer.
The panel said in its assessment report that about 99 percent of banned ozone-depleting substances (ODS) — such as tropospheric chlorine and bromine — contributed significantly to the recovery of the ozone layer, thereby reducing human exposure to harmful Gone. Ultraviolet (UV) rays from the sun.
While ODS significantly alter the ozone layer, the three major greenhouse gases – CH4, N2O, and CO2 – also cause changes in the dynamics of the stratosphere, thus affecting the ozone layer. These gases increased during the industrial era and continue to increase, further affecting ozone trends in the stratosphere.
The panel saw a gradual increase in the size of the ozone hole over the Antarctic between 2019 and 2021 due to meteorological conditions such as the Australian wildfires. But with continued implementation of this protocol, they noted, the Antarctic ozone layer is expected to recover to its 1980 values by 2066. The same will apply to the ozone layer over the Arctic by 2045 and worldwide by 2040.
It also noted that the ozone layer in the upper stratosphere is recovering while the lower stratosphere shows little sign of recovery.
‘Reduce greenhouse gases, limit temperature rise’
The panel, which includes a large international group of experts including experts from the World Meteorological Organization, the United Nations Environment Program, and the National Aeronautics and Space Administration, presented its findings Monday at the 103rd annual meeting of the American Meteorological Society.
The report also states that the 2016 Kigali amendment to the Montreal Protocol requires reducing the production and consumption of several hydrocarbons that contribute greatly to rising temperatures and avoid 0.3-0.5°C of global warming by 2100. is estimated.,
“Ozone action sets a precedent for climate action. Our success in phasing out ozone-eating chemicals shows us what can and should be done,” said Peteri Taalas, Secretary General of the World Meteorological Organization. must be done – urgently – to transition away from fossil fuels, reduce greenhouse gases and limit temperature rise”.
The panel also explored the impact of stratospheric aerosol injection (SAI), an intentional addition of aerosols to the stratosphere, to reduce global warming by increasing the reflectance of the sun’s rays. The exercise helped to identify and warn of potentially harmful consequences, such as a deepening of the Antarctic ozone hole, and delayed ozone recovery, which “could also affect stratospheric temperatures, circulation, and ozone production and destruction rates and transport”. Is”.