Signal Stratospheric ozone at 285.7 DU, above the 277 DU boundary

Summary

The ozone boundary is measured as mean stratospheric ozone outside the polar regions, between 60 degrees north and 60 degrees south. The report takes the 1964 to 1980 average of 292 Dobson units as its reference and places the boundary 5 percent lower, at 277.4 DU. The data series ends in 2022, and the current value of 285.7 DU sits above the boundary, within the safe range. Since the mid-1990s the ozone layer has largely recovered thanks to international agreements that restricted ozone-depleting substances. The report cautions, however, that recovery may have stalled in recent years and that values remain below mid-twentieth-century levels. The 2026 edition also discusses Southern Hemisphere trends, the vertical structure of ozone and new risks such as re-entering space debris.