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UNIT 1: WHERE DO WE STAND? THE STATE OF THE GLOBAL ENVIRONMENT
013
Global CFC production
1,000 tonnes of ozone-depleting potential/year
1,200
1,000
800
600
400
industrialized countries
developing countries
CFC production
has fallen from
a peak of more
than 1 million
tonnes a year to
160,000 tonnes
in 1996 as a
result of the
Montreal
Protocol
200
0
1986 1989 1990 1991 1992 1993 1994 1995 1996
Source: UNEP 1998a/Published in Global Environment Outlook 2000, UNEP
Current ozone losses and UV-B increases
S
E
C
T
I
O
N
1
ozone
loss (%)
Northern Hemisphere, mid-latitudes, winter/spring 6 7
Northern Hemisphere, mid-latitudes, summer/autumn 3 4
Southern Hemisphere, mid-latitudes, year-round 5 6
Antarctic spring 50 130
Arctic Spring 15 22
Note: figures are approximate and assume other factors, such as cloud cover,
are constant
UV-B
increase (%)
Source: WMO, UNEP, NOAA, NASA, and EC (1998)/ Published in Global Environment
Outlook 2000, UNEP
Impacts of Ozone Layer Depletion
As the ozone layer thins, higher levels of UV-B radiation reach and damage life on
earth. This can cause:
• Increases in the pace of global warming and climate change;
• More cases of sunburn and skin cancers in humans;
• More cases of cataract, snow blindness (actinic karatitis) and other
chronic eye diseases;
• Damage to immune systems, reducing human and animal resistance to
infections and diseases including cancers, allergies, and diseases such
as malaria, leishmaniasis and herpes, where the body’s major defence
system is the skin;
• Damage to crops (smaller plants, lower yields and nutritional value)
and to natural ecosystems in the form of altered plant structures and
growth patterns, and changes in the competitive balance between
plants and consequently the animals that consume them: such
changes have already been recorded on detritus organisms, plant
pathogens and pests;