Problem 14
What are the three most important sinks for methane in the atmosphere? Which one of them is dominant? What is meant by the term clathrate compound?
Problem 15
Is the enhancement of the greenhouse effect by release of methane from clathrates due to increased temperature an example of feedback? If so, is it positive or negative feedback? Would an increase in the rate and amount of photosynthesis with increasing temperatures and \(\mathrm{CO}_{2}\) levels be a case of positive or negative feedback?
Problem 16
Explain in chemical terms what is meant by nitrification and denitrification. What are the conditions under which nitrous oxide production is enhanced as a by-product of these two processes?
Problem 18
Are the proposed CFC replacements themselves greenhouse gases? Why is their emission considered to be less of a problem in enhancing the greenhouse effect than was that of the CFCs themselves?
Problem 19
By which two mechanisms does light interact with atmospheric particles?
Problem 20
Explain how sulfate aerosols in the troposphere affect the air temperature at the Earth's surface, by both the direct and indirect mechanisms.
Problem 21
List four important signs, other than increases in average air temperature, that global warming is occurring.
Problem 22
Define the terms geoengineering and solar radiation management.
Problem 23
Describe how the use of sunlight reflectors in space could reduce global warming.
Problem 24
Describe how the scheme of increasing stratospheric sulfate concentration could reduce global warming. Why is particle size an important factor? What schemes have been suggested by which the sulfate could be delivered to the stratosphere?
