Antarctic ozone depletion. Coloured satellite map of atmospheric ozone in the southern hemisphere on September 15 1999. The ozone hole (pale blue) ove

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Antarctic ozone depletion. Coloured satellite map of atmospheric ozone in the southern hemisphere on September 15 1999. The ozone hole (pale blue) over Antarctica (dark blue) is at its 1999 maximum of million square miles. The ozone layer's thick- ness is measured in Dobson Units (DU) with 300 being an average figure. The map is colour-coded: yellow to orange (300-340 DU), green to blue (200- 280 DU) and dark blue (100-200 DU). The ozone hole is due to atmospheric pollution by halogen compou- nds from halons like CFCs (chlorofluorocarbons). It is greatest around October during the Antarctic spring. Data from the TOMS (Total Ozone Mapping Spectrometer) instrument on the TOMS-EP satellite.

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Size: 3543px × 2657px
Photo credit: © NASA/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: 15/9/99, 1999, antarctic, antarctica, atmosphere, depletion, earth, earths, hole, imagery, map, mapping, ozone, science, sciences, spectromet, toms, total