Antarctic ozone hole in 2024: A return to the average
Over the past four years, the annual Antarctic ozone hole has persisted longer than usual, closing in the latter half of December. However, 2024 has deviated from this pattern. According to near real-time tracking by the Copernicus Atmosphere Monitoring Service (CAMS), the ozone hole started to close in early December, aligning more closely with historical averages, reports a Kazinform News Agency correspondent, citing the Copernicus Climate Change Service.
The ozone hole’s development in 2024 was unique in several ways. It began later than usual due to two sudden stratospheric warming events in July, which disrupted the polar vortex. As the polar vortex re-established in August, the chemical depletion of stratospheric ozone over Antarctica resumed its typical cycle. By late September, the ozone hole reached a maximum size of 22 million km², smaller than the peaks observed in 2023 and 2022, which were approximately 25 million km². The 2024 maximum occurred later in the season but was consistent with long-term averages.
Laurence Rouil, Director of CAMS at ECMWF, stated: “The Montreal Protocol and its subsequent amendments have been highly effective in curbing emissions of ozone-depleting substances, but there is still some variability in this process due to the natural variation of the other atmospheric variables at play. Hopefully, we will see the first signs of recovery of the ozone hole in the coming decades.”
Throughout October, the ozone hole steadily decreased in size, closely mirroring the historical average. By November, it had stabilized at around 10 million km² per day, eventually closing as the polar vortex broke down in early December. This timing brought the 2024 ozone hole closure in line with the 1979-2021 average closure date.
