Smaller Hole In The Ozone Layer

The hole that forms each year in stratospheric ozone above Antarctica was smaller in 2013 than it has been in recent years, the National Oceanic & Atmospheric Administration says. In this illustration, created with NOAA satellite data, red designates an area of stratospheric ozone concentration of less than 220 Dobson units—the ozone hole. The data, which NOAA dubs preliminary, show this year’s single-day maximum extent of ozone depletion to be some 7.3 million sq miles on Sept. 26. That’s significantly smaller than the single-day maximum record ozone hole of 11.4 million sq miles set in 2006. Scientists can’t say whether this year’s results show the ozone layer is recovering from the deleterious effects of synthetic chemicals such as chlorofluorocarbons in the atmosphere, says Bryan Johnson of NOAA’s Earth System Research Laboratory. “But” he says, “it is certainly good news.”