1. How are scientist able to make projections about the levels of carbon dioxide 50 years from now?

Question

2. Previous episodes of global warming were not caused by humans. Should we be concerned about global warming that is caused by humans? Explain your answer.

3. Why would ash and particles in the atmoshere cool the Earth?

4.How would more marine plants lower global temperatures?

5. What negative effects might you expect from wide-scale fertilizing of the ocean? How would more marine plants affects local ecosystems?

Answer 1

1. the can use current graphs and mathematically extending them using co2's current rate of acceleration. it looks like a j curve.

2. previous periods of global warming were caused by greenhouse gasses being released in a massive quantity, likely by volcanic activity. we should be concerned because we are doing this artificially. these previous episodes of warming had drastic ramifications like ice ages and near ocean stagnations.

3. Ash released into the upper atmosphere would block the sun's rays and directly cause the earth to cool.

4. plants use photosynthesis which removes greenhouse gasses from the atmosphere. this lowers global temperatures.

5. world wide fertilization of oceans would at first cause an explosion of aquatic plant life. when these plants die, they sink to the bottom and be decomposed by bacteria which use up oxogen. this would greatly lower the dissolved oxogen level of the oceans which would kill off life and possibly cause the oceans to become stagnant. this would happen locally and globally.

Answer 2

This site should help

http://geology.about.com/