Second Exam 2008
Time Limit 4 hours
1) Please read the attached article on methane and answer the following questions.
a) Why it so surprising that plants emit methane under well oxygenated conditions in the environment?
b) What makes methane such a significant greenhouse gas?
c) Why is the production of significant amounts of methane from normal vegetation sending climate modelers “back to the drawing board”?
2) The hydroxyl radical has often been described as the detergent for the atmosphere. The figure below shows the global distribution of OH at the base of the atmosphere and a profile taken above at rain forest in Africa. Explain global distribution of OH and the shape of the vertical profile.
3) Describe the major physical and chemical processes responsible for the production of ground level ozone pollution (smog). Using the data shown in Appendix A, comment on the recent claim that current pollution levels in Maine are caused by emissions in Southern New England.
4) Colby is a major consumer of fossil fuel used for heating and electrical generation for the campus. Using the data in Appendix B, predict the relative concentration and chemical form of sulfur and nitrogen deposition to central Maine over the next six hours. Please be as specific as possible.
5) The addition of sulfate to the stratosphere by volcanic eruptions has been demonstrated to create global cooling by increasing the global albedo. How much would the average global albedo have to change to decrease the average temperature of the earth by one degree Kelvin?
Appendix A: The map below is generated from the NOAA HYSPLIT web page using real atmospheric data for the last 96 hours.
The HYSPLIT trajectory map shows an aerial (plan) view of the path(s) an air parcel(s) took, and a vertical view of its movement at different altitudes. Symbols are used along each trajectory to indicate the position of the air parcel over the calculational period, the interval of which can be defined by the user.
The vertical view at the bottom of the map shows the height of the air parcel measured at these corresponding tick marks. The height of the air parcel is measured in meters above model ground level (AGL).
Appendix B. Waterville is in the center of the map. Dispersion map for a plume emitted from Waterville.