A burgeoning hole in Earth’s stratospheric ozone was first published in a scientific paper in 1985. Scientists determined the cause to be ozone-depleting substances — long-lived artificial halogen compounds.
In a recent study, researchers at Columbia University examined the greenhouse warming effects of ozone-depleting substances and have found that they caused about a third of all global warming from 1955 to 2005, and half of Arctic warming and sea ice loss during that period. They, thus, acted as a strong supplement to carbon dioxide, the most pervasive greenhouse gas; their effects have since started to fade, as they are no longer produced and slowly dissolve. In the 1980s, a hole in Earth’s stratospheric ozone layer, which filters much of the harmful ultraviolet radiation from the sun, was discovered over Antarctica. Scientists quickly attributed it to ODS. The world sprang into action, finalising a global agreement to phase out ODS. The Montreal Protocol, as it is called, was signed in 1987 and entered into force in 1989. Due to the swift international reaction, atmospheric concentrations of most ODS peaked in the late 20th century and have been declining since. However, for at least 50 years, the climate impacts of ODS were extensive, as the new study reveals.
Scientists at Columbia’s School of Engineering and Applied Science and the Lamont-Doherty Earth Observatory used climate models to understand the effects of ODS on Arctic climate. According to Lamont-Doherty researcher Michael Previdi, “We showed that ODS has affected the Arctic climate in a substantial way.”
According to Lorenzo Polvani, lead author of the study and a professor in Columbia’s Department of Applied Physics and Applied Mathematics, “Climate mitigation is in action as we speak because these substances are decreasing in the atmosphere, thanks to the Montreal Protocol, in the coming decades, they will contribute less and less to global warming. It’s a goodnews story.” — ANI
Researchers at Columbia University examined the greenhouse warming effects of ozone-depleting substances (ODS) and found that they caused about a third of all global warming from 1955 to 2005. They also caused half of Arctic warming and sea ice loss during that period.
The ODS acted as a strong supplement to carbon dioxide, the most pervasive greenhouse gas. ODS were developed in the 1920s and ’30s and became popularly used as refrigerants, solvents and propellants.
In the 1980s a hole in Earth’s stratospheric ozone layer was discovered over Antarctica. Scientists attributed it to ODS.
The world sprang into action, finalising Montreal Protocol, a global agreement to phase out ODS in 1987 and entered into force in 1989. Atmospheric concentrations of most ODS peaked in the late 20th century and have been declining since.
Matter referenced:
Times of India, Mumbai, Monday, 26th January, 2020.
By: Dr. Bhawana Asnani.
Happy to see Reviews, Additions, Suggestions and Comments, further.
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