The ozone hole will continue to shrink in 2022

The ozone layer hole The annual occurrence in Antarctica averaged 23.2 million square kilometers between September 7, 2022 and October 13, 2022. This depleted area of ​​the ozone layer over Antarctica was slightly smaller than the average last year For the same period the general trend to decrease in volume observed in recent years continued.

“Over time, steady progress is being made and the hole gets smaller and smaller,” said Paul Newman, chief Earth science scientist at NASA’s Goddard Space Flight Center. “We see some volatility, with weather changes and other factors causing the numbers to vary a little from day to day and week to week. But, overall, we see it’s been declining over the past two decades. By implementing the Montreal Protocol, the elimination of ozone-depleting substances is reducing the hole “.

The Ozone Layer It is part of the stratosphere that protects our planet from the sun’s ultraviolet rays, and starting in September this layer thins to form an “ozone hole” over the South Pole. The chemically active forms of chlorine and bromine, released into the atmosphere from compounds produced by human activity, are associated with high polar clouds each Southern Hemisphere winter (Australian winter). When the sun rises, at the end of winter in Antarctica, chlorine and bromine start chemical reactions that destroy ozone.

Researchers from NASA and the National Oceanic and Atmospheric Administration (NOAA) detect and measure the growth and decay of the ozone hole with instruments aboard the Aura, Suomi NPP and NOAA 20 satellites. Those satellites observed that the ozone hole reached its largest expansion one day on October 5, 2022 , to reach 26.4 million square kilometers (10.2 million square miles), an area slightly larger than that observed the previous year. The map at the top of this page shows the size and shape of the ozone hole over Antarctica on that day.

When the polar sun rises, NOAA scientists also take measurements with a Dobson spectrophotometer, an optical instrument that records the total amount of ozone between the surface and the edge of space; This amount is known as the total column ozone value. Globally, the total average column ozone is about 300 Dobson units. On October 3, 2022, scientists recorded the lowest value of the total column ozone over the South Pole, at 101 Dobson units. At the time, there was almost no ozone at altitudes between 8 and 13 miles (14 and 21 kilometers), in a very similar pattern to last year.

Some scholars were concerned about Possible stratospheric effects From the eruption of the Hengja Tonga-Hung Hapai volcano in January 2022. The eruption of Mount Pinatubo in 1991 released large amounts of sulfur dioxide which inflated the ozone layer. However, no direct hits from Hunga Tonga were detected in stratospheric data from Antarctica.

See the latest state of the ozone layer over Antarctica using NASA’s Ozone Monitoring Program.

NASA Earth Observatory images by Joshua Stevens, using data provided by the NASA Ozone Observatory Program and GEOS 5 model data from the NASA Goddard Space Flight Center Global Office for Modeling and Absorption. Video produced by NASA’s Goddard Space Flight Center. (Reporting by Catherine Cowdrey of the NASA Earth Science News Team.

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