Overview
- On Wednesday, September 16, the World Meteorological Organization said 2025 produced an Antarctic ozone hole that was unusually small and marked the second straight year with both horizontal extent and vertical depth below the 1990–2010 average.
- The WMO attributes the improvement to the Montreal Protocol’s phased ban on ozone‑depleting chemicals such as chlorofluorocarbons and says the layer has been recovering since about 2000 with full restoration likely within several decades.
- WMO scientists reported that ozone fell in some northern‑hemisphere areas in 2025 because of short‑term weather patterns, not because of Antarctic‑style chemical depletion, and they noted the Arctic shows a long‑term recovery trend.
- Parts of Europe have seen up to a 20 percent rise in UV radiation since the mid‑1990s driven mainly by fewer clouds and longer sunshine, which raises risks for skin cancer and eye damage and makes targeted UV protection important.
- The WMO’s annual Ozone Bulletin and World Ozone Day updates underline two policy lessons: global agreements can reverse large environmental harms, but steady monitoring, public‑health advice, and enforcement will matter as recovery unfolds over decades.