Choose A or B and do C and D

A) 1) Find your own choice of website that gives CO2 or H2O footprint information for some type(s) of industrial or agricultural goods, give the URL,and 2) summarize the info on it, 3) say what info surprised you and 4) compare the gms/$ or liters/$ multipliers you get from the info (you may have to compute this from info on the site, including getting a price for the products from somewhere) to ones you get from my Reader data tables for the Gross Approximation used in making your footprints. 1-2 pages

OR

B) Summarize Garret Harden’s arguments in his article in our Reader, The Tragedy of the Commons, and support or argue with his conclusions. Compare his major points to those of Malthus, also in our Readers. 2 to 4 pages

C) On the graphic page is presented information on the history of climate over the last 400,000 years. This comes from ice cores drilled out of the Antarctic Icecap.

1) Please examine the curves carefully and from the curves for CO2 and Methane write down the maximum concentration values these gases have reached in previous natural climate cycles (pay attention to the units, which are given along the vertical axes; 2) what values have these reached in the very recent past, and what dates are listed for those? How do they compare to the previous peaks? 3) Have temperature, carbon dioxide and methane concentrations changed faster in the rise of temperature or in the fall of it?

D) Various alternative explanations to human-caused global warming have been offered. Choose two from the list below and explain what evidence allows them to be confirmed or denied, and how the evidence is acquired.

a) The Sun varies in brightness and that is going on now

b) The shape and orientation of the Earth’s orbit varies

c) Cycles in volcanism are changing the CO2 content of the atmosphere

d) There is no global warming; the data are faked by scientists anxious for more grant money for their research

1-2 pages. Start with this site: http://www.skepticalscience.com/ Cite your references.