The ozone depletion over the Arctic hit a record high in March. It was the biggest and even worse recorded hole since 2001.
The UN World Meteorological Organisation on Friday said that the whole is now closed. This was first announced on April 23rd, by the Copernicus Atmosphere Monitoring Service (CAMS), the European Union's earth monitoring programme.
The hole had suddenly reached a record high in March due to the presence of ozone depleting chlorofluorocarbons in the atmosphere, and an extremely cold winter in the stratosphere, WMO spokeswoman Clare Nullis told a UN briefing in Geneva, as reported by India Today.
The hole was equal to an area 3 times the size of Greenland.
A German scientist had detected the depletion a month ago. "In the areas where the thickness of the ozone layer is at its maximum, the loss is around 90%," said Markus Rex, head of the department for atmospheric physics at the German Alfred-Wegener Institute, in March, as reported by DW.
Initially, several people on CAMS's twitter handle commented that the phenomena was due to the global Covid-19 lockdown. This plugging of the Ozone Layer, however, has nothing to do with the lockdown.
According to scientists, it has been driven by an unusually strong and long-lived polar vortex, the high-altitude currents that bring cold air to the polar regions. This is not related to change in air quality.
The reason behind the Ozone Layer healing, CAMS explained was the extremely powerful vortex with really cold temperatures inside. About the surprising phenomena, scientist Antje Inness said that at the moment it is unclear why the dynamics were so unusual this winter.