Over the last month, a weird new hole in the ozone later has formed over the Arctic and looks to become the largest on record for the region also, it is expected to disappear.
Ozone is a gas made up of three oxygen atoms (O3)The ozone layer is a thin section of the Earth’s atmosphere that absorbs nearly all of the sun’s damaging ultraviolet (UV) light. It is a layer or shield of Earth’s stratosphere that absorbs most of the Sun’s ultraviolet radiation. The Ozone layer is a ring of protective gases around the Earth that absorbs dangerous ultraviolet rays before they reach the surface.
Damage
Ozone layer damage is more like a really thin spot than a hole. The ozone layer damage is thinnest near the poles, especially the South Pole. As the ozone layer thins, more ultraviolet light enters the Earth’s atmosphere. A forest pathologist examines pines damaged by ozone in San Bernardino National Forest, California. Ozone in Earth’s lower atmosphere is created by people, from vehicle gases and industrial emissions. Ozone pollution can damage plants and cause respiratory problems in people.
The Formation
Ozone forms a protective blanket in the stratosphere, about 10 to 50 kilometres above the ground, where it shields from solar ultraviolet radiation. But each year in the Antarctic winter, frigid (freezing) temperatures allow high-altitude clouds to combine above the South Pole.
The Antarctic ozone hole forms every year because winter temperatures in the area routinely plummet, allowing the high-altitude clouds to form. These conditions are much rarer in the Arctic, which has more variable temperatures and isn’t usually primed for ozone depletion, says Jens-Uwe Grooß, an atmospheric scientist at the Juelich Research Centre in Germany.
However this year, powerful westerly winds moved around the North Pole and caught cold air within a ‘polar vortex’. There was more cold air above the Arctic than in any winter recorded since 1979, says Markus Rex, an atmospheric scientist at the Alfred Wegener Institute in Germany. In chilly temperatures, high-altitude clouds are formed and the ozone-destroying reactions start.
The strange hole, in the past few weeks, scientists and space organisations have tracked from space and the ground over the past few days, has reached a record. Marcus Rex told Nature that the Arctic ozone hole didn’t threaten human health over the next month. There might be a possibility that it might drift over more populated areas. He recommended more sunscreen. However, the hole is to disappear in a few weeks.
Maps of the Arctic Hemisphere by NASA’s Ozone Watch created satellite data that shows the hole growing in size from end last year till now. The hole looks set to break up in the coming weeks but not before setting a new record in ozone layer exhaustion at the North Pole.
This is rare and unusual because an opening in the Ozone layer appears every spring over the Antarctic, but the last time this phenomenon was seen in the North was in 2011. In the past, mini ozone holes have hardly been spotted over the North Pole, but the exhaustion over the Arctic this year is much larger compared to previous years.
Source: NASA Ozone Watch & Nature
Diego Loyola, from the German Aerospace Center, remarks, “The ozone hole we observe over the Arctic this year has a maximum extension of less than 1 million sq km. This is small compared to the Antarctic hole, which can reach a size of around 20 to 25 million sq km with a normal duration of around 3 to 4 months.”
“The hole is principally a geophysical curiosity,” said Vincent-Henri Peuch, the director of the Copernicus Atmosphere Monitoring Service. “We monitored unusual dynamic conditions, which drive the process of chemical depletion of ozone. [Those dynamics] allowed for lower temperatures and a more stable vortex than usual over the Arctic, which then triggered the formation of polar stratospheric clouds and the catalytic destruction of ozone.”
The hole is not related to COVID-19 shutdowns that have cut down air pollution and reduced greenhouse gas emissions.
While the hole over the Arctic is a rare event, a much larger hole in the ozone layer over the Antarctic has been a major cause for anxiety for more than four decades.
The Antarctic ozone hole was the smallest in 35 years last November, showing success of efforts to cut the production of the harmful pollutants. The ozone layer protects the Earth from dangerous levels of ultraviolet radiation from the sun.
Even this unusual large hole in the ozone layer is considerably smaller than the more known hole over Antarctica, according to the ESA release. It can grow to be as much as 25 million square kilometres and the new Arctic hole is around 1 million square kilometres in size.
It continues unclear what to expect in the coming years. While the larger ozone hole was caused in part by extreme weather, which has been linked to climate change, it’s too soon to state that the Arctic ozone layer exhaustion will continue to get worse if climate change continues not to control.
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