Ozone layer on track to heal as 2025 Antarctic hole becomes fifth smallest since 1992, says NASA

A quiet shift high above the icy Antarctic sky has caught scientists’ attention this year, as new measurements hint at a slowly healing ozone layer. The data has renewed a simple question: is the atmosphere finally beginning to recover after years of severe damage?

Ozone hole size and NASA–NOAA findings
NASA and NOAA teams reported an annual maximum of 8.83 million square miles on September 9. They said this made it the fifth smallest hole since 1992. They confirmed the slow healing trend using long-term satellite observations from Antarctica. They linked the progress to the Montreal Protocol agreement from past decades. They noted the ban on ozone-destroying chemicals remains effective today.

Why is the timing of the hole important this season?
The depletion season lasted from September 7 to October 13. The hole reached an average size of 7.23 million square miles then. The hole usually grows largest during this short seasonal window. It starts shrinking once the depletion period ends in mid-October. Scientists said the hole is breaking up three weeks earlier in 2025. They compared this shift to patterns seen over the last decade.

Why scientists believe recovery is underway
NOAA scientist Stephen Montzka said harmful compounds declined sharply. He said the drop reached nearly one-third since 2000. These chemicals once came from older aerosols and cooling systems. They include chlorine and bromine from human activities. These gases rise into the stratosphere over many years. They then break down the protective ozone shield above Earth.

How important is the ozone layer for daily human life?
It sits between 7 and 31 miles above the surface. It filters dangerous ultraviolet rays from sunlight. It protects people, animals and plant life worldwide. Without it, UV exposure would rise across the planet.