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