human+impact+on+natural+world

Human Interference with the water cycle (p.499) 1. What are the three ways humans disrupt the natural water cycle? withdraw water from aquifiers they clear vegetation from land and build roads and buildings that prevent percolation and increase runoff they interfere with the natural processes that purify water and instead add pollutatnts 2. What is groundwater mining and what is the danger of this process? withdrawing from aquifiers is groundwater mining and the danger is running out of freshwater in areas using this 3. Why is it possible to run out of freshwater, a renewable resource? because it is possible to run out of freshwater when the available supply runs off instead of entering bodies of freshwater and quifiers or has become so polluted that it is not usable

Human Interference with the carbon cycle (p.501) 1. How are humans increasing the amount of carbon dioxide being deposited in the atomosphere on top of "natural" sources? largely due to the burning of fossil fuels and the destruction of forests to make way for farmland and pasture 2. What are the greenhouse gases and what are the human causes of these gases? carbon dioxide, nitrous oxide, methane, carbon dioxide is being emitted from humans through cars fertilizers are causing an increase in nitrous oxide and methane from bacterial decomposition particularly in the guts of animals 3. Why are these gases called greenhouse gases? just like the panes of a greenhouse they allow solar radiation to pass through but hinder the escape of infared rays back into space 4. What are some possible dangers of global warming? rise of sea levels in coastal areas, extinction of endangered species

Human Interference with the Ozone Shield (p.506) 1. What is the ozone shield and what chemical reaction produces ozone? a layer of ozone that absorbs most of the ultraviolet rays of the sun so that fewer rays strike the earth. Ozone forms when ultraviolet radiation from the sun splits oxygen molecules and then the oxygen atoms combine with other oxygen molecules to produce ozone 2. What are ozone holes? sever depletions of the ozone layer 3. Why are ozone holes dangerous to humans? rise in cateracts and nonmelanoma skin cancer for every 10 percent drop in the ozone level 4. What human pollution destroys ozone molecules? CFC 5. What are commons sources of chlorine pollution? used as a coolant found in refrigerators and air conditioners Human Interference and the Arctic (p. 507) 1. What does ANWR stand for and what is it? Arctic National Wildlife Refuge, wildlife refuge 19 million acres of protected land home to many animals 2. Why is ANWR the source of political debate? because some people want to drill there to get crude oil so prices of gasoline will go down because the US will not have to import as much oil but the problem is it is on a wildlife refuge. Should America choose conveniance over animals lives 3. What are the benefits of drilling for oil in ANWR? price of gas would go down. reduce foreign dependency on oil 4. What are the risks of drilling for oil in ANWR? animals would be endangered and possibly become extinct. If we allow this huge refuge to be plundered what does that say about how we regard our enviornment and wildlife.