The Ozone Hole

• NON-ozone-hole UV AZ
• Human-caused Problem C¹⁴
• Ongoing 2010 Slow Recovery
• Antarctic Argentina, NZ
• Arctic, to Alaska, N Europe

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Where is atmospheric Ozone?

• Stratospheric
  O₂ + UV radiation => (O + O)
  O + O₂ => O₃
• Tropospheric layer

What does ozone do?

Shields Earth from Ultraviolet Radiation
• almost all UV-C (100-280 nm) - lethal
  water purification
• half of UV-B (280-315 nm) - also damaging
• some of UV-A (315-400 nm)

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What is the "ozone hole" Cycle?



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What is the future of the "ozone hole"? (global warming?) (+)


2050   Newman, P. A., Nash, E. R., Kawa, S. R., Montzka, S. A. and Schauffler, S. M. 2006. When will the Antarctic ozone hole recover? Geophysical Research Letters 33: L12814.

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What is destroying stratospheric ozone?

Chlorofluorocarbons (CFC's) are 100% man-made include freons (used as coolants, propellants, cleaners, plastic foam production - once a $28B industry
• Bromine (Br) (and other halons) can also destroy ozone
• N₂O NO(nitric oxide) NO₂ (not prohibited by Montreal protocol) Sci09 Sources CFCs/N2O

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Why are ozone holes at the poles?

Why should we be concerned?

• sunburn skin pigmentation
• cancer - three main types
  skin cancer up 34% between 1973 and 1992
  • squamous-cell and basal-cell
    • UV-B causes sunburn, cancer
  • melanoma (pigmented areas [e.g., moles]) spreads fast, 25% death rate
    • UV-A less harmful, but also causes cancer
• cataracts
• suppresses the immune system

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HUMAN IMPACT!

• 1930 CFC's first synthesized
• 1964 Rowland & Molina predict ozone destr.
• 1980s Antarctic ozone hole observed [xlink]
• 1987 Montreal Protocol reduces CFC-s
• 1988 Dupont ceases production of CFC-s
• 1992 Copenhagen Ammendment impact
• 1995 Rowland & Molina get Nobel Prize
• 2006 largest before 2011
• 2007 Copenhagen effect, but Global Warming!
• 2009 N₂O ozone-depletion Modeling sources
• 2011 Arctic Ozone Hole "Surprise" Monnett vindicated

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