International Environmental Policy: Controlling Ozone Depletion

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International Environmental PolicyControlling
Ozone Depletion
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Ozone The Basics

• Ozone is a naturally occurring gas in the
  atmosphere.
• An ozone molecule contains three oxygen atoms
  O3.
• Ozone is found in two layers
• Bad ozone 10 of ozone is in the lower
  atmosphere (troposphere), where it is a toxic
  component in smog.
• Good ozone 90 is found in the ozone layer
  in the stratosphere (6 to 10 miles above the
  earth), where it blocks harmful UV-B radiation.

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Ozone The Basics
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Benefits of Good Ozone

• If the ozone layer did not absorb ultraviolet
  (UV)-B radiation from the sun, people would
  suffer more
• Skin cancer
• Cataracts
• Suppressed immune systems

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Ozone Depletion

• Stratospheric ozone is depleted by reactions with
  chemicals produced as gases at ground level.
• Important ozone-depleting gases
• Chlorofluorocarbons (CFCs) and other
  chlorine-containing gases, formerly used in
  refrigeration, air conditioning, and other uses.
• Bromine-containing gases (mostly halons),
  originally developed to extinguish fires.

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Ozone Depletion

• Stratospheric ozone concentrations have dropped
  by about 3, on average, since the 1980s.
• Ozone concentrations have fallen more near the
  poles, and not at all near the equator.

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Ozone Depletion

• Estimated changes in surface UV radiation from
  1979 to 1992

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Ozone Depletion

• The link between man-made chemical emissions and
  depletion of the stratospheric ozone layer was
  discovered starting in the mid-1970s.
• The most important step in preventing ozone
  depletion
• Montréal Protocol on Substances that Deplete the
  Ozone Layer (1987)

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Montréal Protocol

• The Montréal Protocol and later amendments
  required a phaseout of production and consumption
  of ozone-depleting chemicals.
• The Montréal Protocol has been ratified by over
  180 nations.
• In the US, the Montréal Protocol was implemented
  in the provisions of the Clean Air Act of 1990.

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Montréal Protocol

• Predicted Effects of the Montréal Protocol

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Montréal Protocol

• To facilitate international cooperation in
  reducing production of ozone-depleting
  substances, the Montréal Protocol
• allowed trading of emission reduction credits
  between countries.
• established a Multilateral Fund to assist
  developing countries in the transition toward CFC
  substitutes.
• Indias annual consumption of refrigerators is
  expected to climb from 6 million in 1989 to 80
  million in 2010, so its participation in the
  Montréal Protocol is crucial.
• India ratified the agreement in 1992.

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Policy Changes in the U.S.

• The Clean Air Act of 1990 ended production of
  CFCs on December 31, 1995.
• Rather than calling for an abrupt ban on
  production, policies were designed to be more
  cost-effective.

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Policy Changes in the U.S.

• Cost-effective provisions
• Congress enacted an excise tax on production of
  ozone-depleting chemicals. The tax was gradually
  raised over time.
• Allowances were issued to producers of
  ozone-depleting chemicals. Over time the number
  of allowances was reduced.
• The 1990 Clean Air Act called for a national
  recycling program for CFCs. Existing supplies of
  CFCs could still be legally used.
• Policies like these provided incentives for the
  development of safer alternatives to
  ozone-depleting chemicals.

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Costs and Benefits of the CFC Phaseout

• The EPA estimated (in 1987) that the costs of
  phasing out CFCs would be 27 billion through
  2075.
• For example, the value of CFCs in
  air-conditioning products was estimated to be
  10.9 billion.
• The EPA estimated that the benefits of
  eliminating CFCs (value of health effects and
  crop damage averted) would be 6.5 trillion.