ANSWERS TO "THE GREENHOUSE EFFECT"
CONTROLLED HYPERTEXT
SPRING, 2003

Directions: Please check your answers. When you have finished checking your answers, please go to The Environmental Science Page of our web site, where you will find links to the texts you need to read to prepare for our collaborative lesson with Prof. Weiss' class

1. The greenhouse effect refers to the warming of the earth caused by the sun's rays penetrating the atmosphere. Pollution causes the heat to become trapped at the surface, increasing the temperature and causing the greenhouse effect.

2. CHOOSE ANY THREE OF THE ITEMS IN BOLD FACE: The greenhouse effect is caused by carbon dioxide, fossil fuels like oil, gas and coal, methane, chlorofluorocarbons (CFCs), and deforestation.

3. If the earth's temperature increased by as few as 2 degrees Celsius, the polar ice caps could melt, causing flooding of cities on the coast.

4. The ozone layer protects the earth from ultraviolet radiation.

5. When ozone reacts with chlorine, the ozone molecules are destroyed. Since nothing happens to the chlorine, it continues to destroy many more ozone molecules.

6. Chemicals such as chlorofluorocarbons have caused a hole to develop in the ozone layer.

7. Ozone depletion is very serious. Without an ozone layer, dangerous UV rays get to the surface of the earth. These rays cause blindness and cataracts, as well as skin cancer, in human beings. The rays also kill the plankton, which are the foundation of the food chain, and this leads to lack of food for higher animals and even human beings. UV radiation also kills plants and crops.

8. The Montreal Protocol was a contract among nations to eliminate chlorofluorocarbons by the year 2000 and to aid third world countries in doing this also.

9. The Kyoto Treaty was the first treaty that legally bound signing nations to adhere to its terms, which were to cut emissions of the major greenhouse gases. Unfortunately many nations have yet to accept the terms of the Kyoto Treaty.

10. Under normal conditions, the Greenhouse Effect maintains the earth at an average temperature of 60 degrees.

11. We can interpret it to mean that the greenhouse effect is getting worse as time goes by. The earth is getting warmer and warmer.

12. Part 1: The nations of the world have met several times and signed several treaties to deal with the problem of global warming. Unfortunately, many nations have not yet agreed to the terms of these treaties. Also many third world nations are not able to do what they need to do to eliminate greenhouse gases.
    
    Part 2: ANSWERS WILL VARY