This map shows ozone concentration over Antarctica in October. Near an altitude of 30km, there is an atmospheric layer that contains relatively high concentrations of ozone. The ozone layer absorbs almost all ultraviolet light (which is damaging to life on Earth), and protects us. Since 1985, ozone concentration decreases from September to November and an ozone hole forms in this period.
Data: Japan Meteorological Agency (the satellite data were provided by NASA)