Ozone Hole Reaches Its 2026 Maximum

What happened

Prior to 1979, scientists had not observed atmospheric ozone concentrations below 220 Dobson Units . But in 1985, British Antarctic Survey scientists using ground-based measurements at Halley Research Station reported that Earth’s natural sunscreen was thinning dramatically over Antarctica each spring.

NASA satellite instruments revealed the continental scale of this Antarctic ozone thinning, and it came to be known as the ozone hole. The data visualizations below shows the ozone hole each year from 1979 through 2026 (no data are available for 1995).

The ozone hole ranked seventh largest by area in 48 years of monitoring, but it was not as deep as other large holes on record. Scientists define the ozone hole as the area in which ozone concentrations drop below the historical threshold of 220 Dobson units.

The stratospheric ozone layer protects life on Earth by absorbing ultraviolet light, which damages DNA in plants and animals (including humans) and leads to sunburns and skin cancer. Earth Observatory 5 min read Image of the Day for November 9, 2026 The ozone hole ranked seventh largest by area in 48 years of monitoring, but it was not as deep as other large holes on record.

The measurements were made from 1979-2004 by the TOMS (NASA’s Total Ozone Mapping Spectrometer) instruments on Nimbus-7 and several additional satellites; from 2005-2011 by the OMI (Ozone Monitoring Instrument) on the Aura satellite; from 2012-2025 by the OMPS (Ozone Mapping and Profiler Suite) on the Suomi NPP satellite; and in 2026 by the OMPS on the NOAA-20 satellite. Red and yellow areas indicate the ozone hole.

As the images show, the word hole isn’t literal; no place is empty of ozone. Scientists use the word hole as a metaphor for the area in which ozone concentrations drop below the historical threshold of 220 Dobson Units .