Environmental Management I
Semester Test 2
October 20th
2 Hours
Marks 85 Marks
Climate Change and Ozone depletion
Question 1
1.1 Very briefly discuss the mechanism for the natural greenhouse effect. How do greenhouse gasses keep the earth warm?
1.2 What greenhouse gasses (name two) contribute to global warming?
(5)
Question 2
Discuss some of the factors affecting the earth's temperature and how those effects will determine the effect of future warming. Include the following factors in your answer and discuss how the factors will influence the temperature.
1. The oceans ability to store CO2 and heat.
2. The effects of cloud cover.
3. The effect of aerosols from outdoor air pollution.
4. The effects of higher CO2 levels on photosynthesis.
5. Effects of a warmer troposphere on methane emissions
(10)
Question 3
Why is climate change such a difficult problem to deal with? Give any three reasons.
(3)
Answer 3
In textbook p479
Question 4
What can be done to reduce greenhouse gas emissions? Give any two possible solutions.
(2)
Answer 4
In textbook p480-p484
Question 5
What causes ozone depletion? Include in your answer the chemicals that lead to destruction of ozone and the actual mechanism for its destruction. You may make a drawing of the chemical changes that occur leading to the destruction of the ozone molecule. Include all of the molecules involved in the chain reaction.
(5)
Answer 5
Textbook p486
Question 6
What is the hole in the ozone layer, where does it form and why does it form there?
(3)
Answer 6
Textbook p487
Question 7
Why is it important for human and animal health that we protect the ozone layer? What are the effects of no doing so?
(2)
Answer 7
Skin cancer is caused by UV radiation not blocked by Ozone.
Hazardous Waste
Question 8
There are two options for dealing with waste (not methods of disposal). What are they and very briefly discuss what is meant by each of them.
(4)
Answer 8
Option 1:
Waste management
Entails dealing with waste after creation
Option 2:
Waste prevention
Prevents generating the waste in the first place
Question 9
There are ways for the consumer to produce less waste which are called the five R's of waste reduction. What are the five R's of waste reduction? List and briefly describe what is meant by each of the R's. You may use an example in your description if you want to.
(10)
Answer 9
Refuse
Escape from affluenze by refusing to buy items that we really don't need
Reduce
Consume less and live a simpler and less stressful life by practicing simplicity
Reuse
Rely more on items that can be used over and over instead of throwaway items. For example, take a refillable coffee cup to the office instead of polystyrene cups.
Repurpose
Use something for another purpose instead of throwing it away. For example, use a tire to make a swing.
Recycle
Separate and recycle paper, glass, cans, plastics, metal and other items and buy products made from recycles materials.
Question10
In the following fictitious scenario, what can the company do to reduce the amount of solid and hazardous waste generated?
(10)
Microsoft produces a portable mp3 player called the Zune. Unfortunately they are not very environmentally responsible in the way they make and sell the Zune. The Zune is sold in a big box made from virgin cardboard with a lot of printed documentation inside. In addition to this it is wrapped with chlorine containing PVC plastic that releases Dioxins when burned. The Zune itself is also made from PVC plastic and contains a number of toxic heavy metals like Mercury (for the backlight), Arsenic (in the glass covering), Chronium (for shiny surfaces) and Poly Brominated Flame Retardants. There is no current take back option by the company and it is very difficult to take the Zune apart for repairs and recycling. It also contains a NiCd battery which cannot be replaced and contains Cd, a hazardous heavy metal. During the manufacturing process, a lot of industrial chemicals are used in addition to organic solvents for making the plastics in the design. The default settings on the Zune software also require the display backlight to be on all of the time as well as the small harddrive in the Zune. This draws additional power from the battery which therefore must be recharged very regularly. The charger plugs into a normal wall outlet and has no on button or indicator lights to show that it is drawing power from the wall outlet. During manufacturing, some of the components are rejected because they have some scratches on them. The scratches can be taken out by polishing but it will mean changing some of the steps in production at an additional initial cost. The discarded components, the organic solvents and waste materials are sent to a hazardous waste landfill site for disposal. New organic solvents are also delivered every day to keep production up. |
Answer 10
Just look at the scenario
Non-renewable energy resources
Question 11
What is net energy?
(1)
Answer 1
The energy doing useful work.
Question 12
If you are using natural gas for industrial heating. How can you calculate the net energy for natural gas. What steps do you need to include and how do you include them in your calculations?
(4)
Answer 12
You have to include and subtract the energy of all the steps that use energy to produce natural gas from the energy gained from burning natural gas including exploration, drilling, extraction, liquefaction, treatment, distribution and energy lost due to inefficient use.
Question 13
What are fossil fuels?
(2)
Answer 13
Fuels that were formed from decaying plant or organic matter. Carbonized fossils of ancient living plants.
Question 14
Give three examples of fossil fuels.
(3)
Answer 14
Oil (Crude)
Gas
Coal
Question 15
Briefly discuss some of the trade-offs (advantages and disadvantages) of using conventional natural gas for energy. You must include at least three advantages and three disadvantages.
(6)
Answer 15
Advantages
Ample supplies
High net energy yield
Low cost (Huge subsidies)
Less air pollution
Lower CO2 emissions
Moderate environmental impact
Easily transported by pipeline
Low land use
Good fuel for fuel cells and gas turbines
Disadvantages
Nonrenewable resource
Releases CO2 when burned
Methane (a greenhouse gas) can leak from pipelines
Difficult to transfer from one country to another
Shipped across ocean as highly explosive LNG
Sometimes burned off and wasted at wells because of low price
Required pipelines
Question 17
Briefly discuss the advantages and disadvantages of using coal to generate electricity. You must include three advantages and three disadvantages.
(6)
Answer 17
Advantages
Ample supplies
High net energy yield
Low cost (huge subsidies)
Well developed mining and combustion technology
Air pollution can be reduced with improved technology
Disadvantages
Severe land disturbance, air pollution and water pollution
High land use (including mining)
Severe threat to human health
High CO2 emissions when burned
Releases radioactive particles and toxic mercury into air
Question 18
Briefly discuss the trade offs of the nuclear fuel cycle (nuclear energy). You must include two advantages and two disadvantages of using nuclear energy.
(4)
Answer 18
Advantages
Large fuel supply
Low environmental impact (without accidents)
Emists 1/6 as much CO2 as coal
Moderate land disruption and water pollution (without accidents)
Moderate land use
Low risk of accidents because multiple safety systems are in place
Disadvantages
Cannot compete economically without huge subsidies
Low net energy yield
High environmental impact if accidents occur
Catastrophic accidents can happen
No widely acceptable solution for long term storage of high level radioactive wastes and decommissioning worn out plants
Subjected to terrorist attacks
Spread knowledge and technology for building nuclear weapons.
Question 19
Briefly discuss some of the threats of terrorism connected to the use of nuclear energy. Include all possible ways in which it threatens national security.
(3)
Answer 19
Different risks include
Attack on nuclear reactor
Use of fissile Uranium-238 or Plutonium-239 to produce a atomic bomb
Use of non-fissile radioactive material to produce a dirty bomb.
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