Effect of CFC ban on the ozone layer

Référence de la vidéo 11920670
Animated models of the projected Antarctic atmospheric ozone levels from 1974 to 2065, comparing the situations with (left) and without (right) the ban on CFCs (chlorofluorocarbons). Ozone levels range from high (red) to zero (dark blue) here, and vary seasonally, being most depleted in the spring. Use of CFCs was banned by the Montreal Protocol in 1989, after work by Frank Sherwood Rowland and Mario Molina showed that they would be carried to the ozone layer and be broken down by solar UV radiation, beginning a process that would destroy ozone. The ozone layer in the stratosphere absorbs much of the harmful UV radiation from the Sun. Measurements showed that there were growing ozone holes, regions of low ozone concentration, over both poles. Since the ban came into effect the holes have stopped growing, and there is some evidence of repair, although CFCs can last around 100 years in the atmosphere. For the same model showing the situation in the northern hemisphere, see clip K001 3281.
Licence : Droits gérés
Crédit : Science Photo Library / NASA / SVS / GSFC
Model Release : Non requis
Property release : Non requis
Durée : 02:00 Minutes
Aspect ratio : 16/9
Restrictions : -

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