
The Montreal Protocol on Substances that
Deplete the Ozone Layer (a protocol to the Vienna Convention for the Protection of the
Ozone Layer) is an international treaty designed to protect the ozone layer by
phasing out the production of numerous substances believed to be responsible
for ozone depletion. The treaty was opened for signature on 16 September 1987,
and entered into force on 1 January 1989, followed by a first meeting in Helsinki, May 1989. Since
then, it has undergone seven revisions, in 1990 (London),
1991 (Nairobi), 1992 (Copenhagen),
1993 (Bangkok), 1995 (Vienna),
1997 (Montreal), and 1999 (Beijing). It is believed that if the
international agreement is adhered to, the ozone layer is expected to recover
by 2050.Due
to its widespread adoption and implementation it has been hailed as an example
of exceptional international co-operation, with Kofi Annan quoted as saying
that "perhaps the single most successful international agreement to date
has been the Montreal
Protocol".
The two ozone treaties have been ratified by 197 states and the European Union
making them the most widely ratified treaties in United Nations history.
EFFECTS OF
MONTREAL PROTOCOL
Since the Montreal Protocol came
into effect, the atmospheric concentrations of the most important
chlorofluorocarbons and related chlorinated hydrocarbons have either leveled
off or decreased. Halon concentrations have continued to increase, as the
halons presently stored in fire extinguishers are released, but their rate of
increase has slowed and their abundances are expected to begin to decline by
about 2020. Also, the concentration of the HCFCs increased drastically at least
partly because for many uses (e.g. used as solvents or refrigerating agents)
CFCs were substituted with HCFCs. While there have been reports of attempts by
individuals to circumvent the ban, e.g. by smuggling CFCs from undeveloped to
developed nations, the overall level of compliance has been high. In
consequence, the Montreal Protocol has often been called the most successful
international environmental agreement to date. In a 2001 report, NASA found the
ozone thinning over Antarctica had remained the same thickness for the previous
three years, however in 2003 the ozone hole grew to its second largest size.
The most recent (2006) scientific evaluation of the effects of the Montreal
Protocol states, "The Montreal Protocol is working: There is clear
evidence of a decrease in the atmospheric burden of ozone-depleting substances
and some early signs of stratospheric ozone recovery."
Unfortunately, the hydro
chlorofluorocarbons, or HCFCs, and hydro fluorocarbons, or HFCs, are now
thought to contribute to anthropogenic global warming. On a
molecule-for-molecule basis, these compounds are up to 10,000 times more potent
greenhouse gases than carbon dioxide. The Montreal Protocol currently calls for
a complete phase-out of HCFCs by 2030, but does not place any restriction on
HFCs. Since the CFCs themselves are equally powerful greenhouse gases, the mere
substitution of HFCs for CFCs does not significantly increase the rate of
anthropogenic global warming, but over time a steady increase in their use
could increase the danger that human activity will change the climate.
Policy experts have advocated for
increased efforts to link ozone protection efforts to climate protection
efforts. Policy decisions in one arena affect the costs and effectiveness of
environmental improvements in the other.
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