Ozone hole ranked as 5th smallest in more than 30 years, according to new research

The ozone hole over the Antarctic is significantly smaller in 2025 than in previous years, ranking as the fifth-smallest it's been since 1992, according to a new report by NOAA and NASA scientists. The ozone hole reached its greatest one-day extent for 2025 in early September, measuring 8.83 million square miles, about 30% smaller than the largest hole on record in 2006. The so-called “ozone hole” is not an actual hole in the planet’s ozone layer, but rather a large region of Earth’s stratosphere with extremely low ozone concentrations. NOAA and NASA scientists emphasize that recent findings show efforts to limit ozone-depleting chemical compounds can have a significant impact. The regulations are established by the Montreal Protocol, which went into effect in 1992. Subsequent amendments a