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South Pole’s Ozone Hole Smallest on Record Since 1980s

Normally, the ozone hole grows to a maximum area of about 8 million square miles around late September to early October

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NASA reported the hole in Earth’s protective ozone layer averaged only 3.6 million square miles. Pixabay

The South Pole’s ozone hole is currently the smallest on record since it was first detected in the 1980s, according to NASA.

NASA reported the hole in Earth’s protective ozone layer averaged only 3.6 million square miles. Normally, the ozone hole grows to a maximum area of about 8 million square miles around late September to early October.

“That’s really good news,” NASA scientist Paul Newman said. “That means more ozone over the hemisphere, less ultraviolet radiation at the surface.”

Ozone in the stratosphere absorbs some of the sun’s harmful ultraviolet radiation. Ultraviolet radiation can cause skin cancer, cataracts, suppress immune systems and damage plants.

South, Ozone, Record
NASA reported the hole in Earth’s protective ozone layer averaged only 3.6 million square miles. Pixabay

However, NASA scientists said the shrinking ozone hole is most likely from weather changes, not recent efforts to cut pollution.

“It’s important to recognize that what we’re seeing this year is due to warmer stratospheric temperatures,” Newman said. “It’s not a sign that atmospheric ozone is suddenly on a fast track to recovery.”

Chlorine in the air needs cold temperatures in the stratosphere and clouds to convert into a form of the chemical that eats ozone, Newman said. The clouds go away when it warms up.

This year temperatures were 29 degrees warmer than average right below the stratosphere.

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Man-made chlorine compounds, which can last in the air for 100 years, damage the ozone, creating a gap. The effects are most evident over the Antarctic, “because of the special atmospheric and chemical conditions that exist there and nowhere else on the globe,” according to the National Oceanic and Atmospheric Administration.

The 1987 international Montreal Protocol banned many of the chlorine compounds used in refrigerants and aerosols, like hairspray, to lessen the damage. Since then, the size of the ozone hole has slowly declined but remains large enough to produce significant ozone loss.

Scientists project the Antarctic ozone to recover back to its 1980 level around 2070.

The hole reaches its peak in September and October and disappears by late December until the next year. (VOA)

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Ozone-Depleting Substance Causes Half of Arctic Warming

Ozone-depleting substances behind half of Arctic warming

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Arctic warming
Ozone-depleting substances caused half of Arctic warming and sea ice loss. Pixabay

Ozone-depleting substances caused half of Arctic warming and sea ice loss from 1955 to 2005, causing about a third of all global warming during that period, reveals a significant study.

A scientific paper published in 1985 was the first to report a burgeoning hole in Earth’s stratospheric ozone over Antarctica.

The discovery left scientists into a huddle to determine the cause which happened to be ozone-depleting substances – long-lived artificial halogen compounds entirely manmade and popularly used as refrigerants, solvents and propellants.

The new study from researchers at Columbia University and published in the journal Nature Climate Change examined the greenhouse warming effects of ozone-depleting substances (ODS).

Arctic warming
Ozone-depleting substances act as a strong supplement to carbon dioxide and had lead to Arctic warming. Pixabay

It found that the ozone-depleting substances acted as a strong supplement to carbon dioxide, the most pervasive greenhouse gas. “We showed that ODS have affected the Arctic climate in a substantial way,” said researcher Michael Previdi from Lamont-Doherty Earth Observatory.

The scientists reached their conclusion using two very different climate models that are widely employed by the scientific community, both developed at the US National Center for Atmospheric Research. The results highlight the importance of the Montreal Protocol, which has been signed by nearly 200 countries.

“Climate mitigation is in action as we speak because these substances are decreasing in the atmosphere, thanks to the Montreal Protocol,” said Lorenzo Polvani, lead author of the study. “In the coming decades, they will contribute less and less to global warming. It’s a good-news story”.

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, finalizing a global agreement to phase out ODS.

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The Montreal Protocol 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, revealed the new study. (IANS)