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Could global warming worsen ozone depletion?

Last updated 08 August 2002
Originally answered 8 August 2002

Full Question

Could global warming worsen ozone depletion?

Answer

There are two schools of thought about how global warming will affect ozone depletion. One school suggests that by keeping more warmth in the lower atmosphere the upper atmosphere will cool making it easier for ice clouds to form and thereby providing greater opportunities for ozone depletion catalysis. The other school suggests that the increased temperature will lead to an increased mass exchange between the stratosphere and the troposphere which will result in a more rapid removal of CFCs and thus a faster recovery of the ozone layer.

Are ozone depletion and climate change linked?

Last updated 08 August 2002
Originally answered 8 August 2002

Full Question

Are ozone depletion and climate change linked?

Answer

According to the UNEP/WMO “Scientific Assessment of Ozone Depletion: 2002,” ozone-layer depletion and climate change are linked in a number of ways, but ozone depletion is not a major cause of climate change. The stratosphere cools when ozone is destroyed because there is less ozone to absorb UV radiation. This cooling in turn affects air motions and chemical processes that are related to climate. In addition, some ozone-depleting gases (and, indeed, ozone itself) are also heat-absorbing “greenhouse gases,” so they play a dual role in climate change and ozone depletion. The potential contributions to climate change from ozone and ozone-depleting gases is smaller than from changes in other important atmospheric gases.