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UNIT 1: WHERE DO WE STAND? THE STATE OF THE GLOBAL ENVIRONMENT
The tourism
industry directly
contributes
towards ozonelayer
depletion,
because it is an
important user
of ODSs for
refrigeration,
air-conditioning
and fireextinguishing,
as well as of
foam insulation,
upholstery, and
aerosol spray
cans.
• Damage to marine and aquatic life through reduced growth
of plants and life forms at the bottom of the food chain
(phytoplankton, zooplankton, juvenile fish, crabs, shrimps etc), which
will subsequently affect the growth of all marine life and reduce fish
harvests;
• Damage to man-made materials through the faster degradation of
paint, plastics and other materials.
The major groups of ozone-depleting substances (ODs) are:
• CHLOROFLUOROCARBONS (CFCS)
First synthesised in 1928, CFCs were widely used as refrigerants in
refrigerators, freezers and air- conditioners, as propellants in aerosol
spray cans, blowing agents in the manufacture of foams, and cleaning
agents for electronic equipment and in dry cleaning.
• HYDROCHLOROFLUOROCARBONS (HCFCS)
First developed to replace CFCs as refrigerants and blowing agents.
Though less potentially ozone-destructive than CFCs, they are
nonetheless too dangerous for long-term use.
• CARBON TETRACHLORIDE AND METHYL CHLOROFORM
(1,1,1-trichloroethane)
These are used as solvents in dry cleaning and many other processes.
• HALONS
Halons contain bromine and are used in fire-extinguishing equipment.
Some halons have an ozone-depleting potential ten times higher than
that of CFCs.
• METHYL BROMIDE
This is used as an agricultural pesticide and to fumigate agricultural
products.
Experts have classified each individual ozone-depleting substance (ODS) according
to its ozone-depleting potential (ODP), on the basis of its atmospheric lifetime,
stability, and reactivity and ozone-depleting capacity, by counting the chlorine or
bromine atoms it contains. All ODP values are expressed in relation to the baseline
value of 1 for CFC-11.
Why Should the Tourism Industry be Concerned about Ozone
Layer Depletion?
The tourism industry directly contributes towards ozone-layer depletion, because
it is an important user of ODSs for refrigeration, air-conditioning and fireextinguishing,
as well as of foam insulation, upholstery, and aerosol spray cans.
Tourists, especially those looking for sunshine and the ‘open air’, are among the
first to feel the impact of high levels of UV B radiation, which is increasing skin
cancers, cataracts, and immunity system diseases. Damage to crops and marine
life also means that key tourist resources will be affected.
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1
International Action to Halt Ozone Layer Depletion
When evidence of the Antarctic ozone hole was first published, nations concerned
about this crisis began negotiations that led to the adoption, in September 1987, of
the Montreal Protocol on Substances that Deplete the Ozone Layer. This identified