Sherwood Rowland and Mario Molina
Cause of Ozone Depletion
Cl atom from CFC can destroy up to 100,000 molecules of O3
1987, Montreal Protocol on Ozone Depletion:
36 countries agreed on phasing out CFC production.
1995 - Rowland and Molina: 1st Nobel Prize on environmental issue.
CFCs (CloroFluoroCarbons) are the cooling agents (in refrigerators, cars), different types of sprays.
Wars cause a combination of all possible environmental problems:
air, water, soil pollution,
nuclear war radioactive waste,
depletion of resources, etc.
Current Environmental Conditions
Half the world's wetlands were lost in the last 100 years.
Land conversion and logging have shrunk the world's forests by 50%.
3/4 of the world's marine fish stocks are over-fished or are being harvested beyond a sustainable rate.
Soil degradation has affected 2/3 of the world's agricultural lands in the last 50 yrs.
industrial: oil /gas industry
Major Causes of Environmental
Degradation (contd): Acid Rain /Deposition
This graph shows the areas impacted by acid rain. The red areas are those most strongly affected. Notice that these areas include regions in New England and Canada, the Northeast, and northern Europe, Scandinavia and England. Some areas of the world (the Pacific Northwest, for instance) aren't impacted as much by acid rain, partly because of their distance coal processing plants that burn low quality coal.
Acid rain isnt always the result of human activity. For example, there is a natural fishery off the coast in the Gulf of Alaska where the surfacing of deep ocean currents produces di-methyl sulfide, which oxidizes in the atmosphere and falls as sulfuric acid. What effect do you think the sulfuric acid would have on the fishery?
Sustainable development:progress in human well-being that we can extend or prolong
over many generations, rather than just a few years.
Sustainable development is defined as actions that satisfy the needs of the present without compromising the ability of future generations to meet their own needs.
The benefits of sustainable development must be available to all humans, not just to the members of a privileged group.
Sustainability of the earth's resources is a key issue. When will the resources that sustain the over-consumption of industrialized nations be exhausted? Some resources are inherently sustainable because they are continuously produced by nature. For instance, forest products can be produced continuously as long as the soil resource is maintained. Other resources, such as oil, take very long time periods to produce naturally.
Date: 2015-12-18; view: 1401