An Arctic ozone hole

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An Arctic ozone hole?

• Arctic vortex
• No land mass (warmer)
• Less symmetric
• Planetary wave activity (Tibet, North America)
• Overlap between cold temperatures and sunlight
  are limited in the Arctic and ozone depletion
  episodic and minor

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Arctic ozone depletion observations Feb-April
1997
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Projected evolution of tropospheric chlorine
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• If our eyes detected only UV radiation the world
  would appear very dark.
• Give a qualitative explanation why the Chapman
  reactions (6.47-6.50) predict a peak
  concentration of O3 at some level in the
  stratosphere.
• In the lower stratosphere, the concentration of
  atomic oxygen decreases rapidly when the sun
  sets. (Hint Consider the Chapman reactions.)
• For catalytic reactions such as (6.58) to be
  efficient, each reaction comprising the cycle
  must be exothermic.
• Elimination of CFCs, to allow restoration of the
  stratospheric ozone layer, could lead to higher
  concentrations of tropospheric pollutants.
• Large amounts of chlorine are present in the
  atmosphere in the form of NaCl, but chlorine from
  this source is not involved in the destruction of
  stratospheric ozone.

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Stratospheric aerosols The Junge layer
Figure 22.
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Sources of aerosols in the stratosphere
Figure 24.
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Effect of volcanoes on aerosols
Pinatubo
Ruiz
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Mt. Pinatubo Optical depth observations