The ozone layer shows encouraging signs: its hole reached the fifth smallest size since 1992 this 2025, according to confirmations by NASA and the NOAA this Tuesday.
This result marks progress in the atmospheric recovery, although there is still a way to go to reverse decades of environmental damage.
Record Dimensions and Historical Comparisons of the Ozone Layer Hole
During the peak depletion season, between September 7 and October 13, the hole in the ozone layer averaged 18.71 million square kilometers.
This extension is equivalent to twice the area of the continental United States.
On September 9, the maximum peak was recorded with 22.86 million square kilometers, a dimension that represents approximately 30% less than the historical record of 2006.
That year, the hole reached an average of 26.60 million square kilometers.
Both agencies highlighted another relevant fact: the hole began to disintegrate almost three weeks earlier than usual in the last decade.
The Montreal Protocol Drives Recovery
Paul Newman, a scientist at the University of Maryland and leader of the research team at NASA’s Goddard Center, noted that “we are seeing that ozone holes tend to be smaller in area than in the early 2000s.”
The expert added that “they are forming later in the season and disintegrating earlier”, although he warned that “there is a long way to go before recovering to the levels of the 1980s.”
Thus, the controls on chemical compounds that deplete ozone, established by the Montreal Protocol in 1987, are proving effective.
This international agreement came into force in 1992 and required countries to replace harmful substances with safer alternatives.
Stephen Montzka, a scientist at NOAA’s Global Monitoring Laboratory, confirmed that “since its peak around the year 2000, levels of ozone-depleting substances in the Antarctic stratosphere have decreased by approximately one-third.”
Newman added a key projection: “This year’s hole would have been more than a million square miles larger if there were still as much chlorine in the stratosphere as 25 years ago.”
At this rate, projections indicate that the ozone layer over Antarctica will fully recover by the end of the 2060s.
The Factors Still Influencing the Ozone Layer Hole
The prohibited chemicals persist in old products like building insulation and landfills.
As these emissions decrease over time, recovery will steadily progress.
Among the factors influencing ozone levels year after year are:
- Temperature of the Antarctic stratosphere
- Regional weather conditions
- Strength of the polar vortex surrounding Antarctica
These natural elements cause variations, but the general trend shows sustained improvements thanks to international compliance with the Montreal Protocol.
The stratospheric ozone layer is on track to fully recover later this century.
