#2

a) how many degrees warmer is the earth’s surface due to the (natural) greenhouse effect compared to what it would be if we had no atmosphere? you can find this answer in the book or on line; it was also cited in class.

b) explain this higher temperature (qualitatively) in terms of the transparency of our atmosphere in a particular wavelength range.

c) by what fraction have humans increased the carbon dioxide (co2) in the atmosphere? this increase started with the industrial revolution, so for your starting concentration, find a value that goes back at least to 1800.