The Planet's Sunscreen: How the Recovering Ozone Layer Sets Your UV Index
The UV number on your phone is shaped by a thin shield miles overhead - and that shield is one of the rare environmental stories getting better.
Thanks to the Montreal Protocol, the ozone layer is on track to recover to 1980s levels by around mid-century, and NASA and NOAA ranked the 2025 ozone hole as the 5th smallest since 1992.
NASA and NOAA scientists frame the shrinking ozone hole as evidence that the Montreal Protocol is working, with the recovering layer expected to curb future UV-driven harm such as skin cancer and cataracts.
Questions we get a lot
How does the ozone layer affect the UV that reaches me?
The ozone layer absorbs a large share of the sun's most harmful ultraviolet radiation high in the stratosphere, effectively acting as a planetary sunscreen. When ozone is thinner, more UV reaches the ground. Its long-term recovery is expected to reduce UV-driven skin cancer and cataracts over time.
Is the ozone layer actually recovering?
Yes. Following the Montreal Protocol's phaseout of ozone-depleting substances, the layer is on track to recover toward 1980s levels by around mid-century. NASA and NOAA ranked the 2025 Antarctic ozone hole as the 5th smallest since 1992, consistent with that healing trend.
Does ozone recovery mean I can ease up on sun protection?
No. Ozone recovery is a long-term, planetary trend that reduces future UV-driven harm, but ground-level UV remains high enough to damage skin and eyes today. Daily sun protection is still warranted whenever the UV index is moderate or higher.
r/askscience: 'If the ozone layer is recovering, does that mean UV levels and skin-cancer risk will go down over time?'