<p> Geography 2412 Fall 2004 Name:______Date:______TA:______</p><p>Exercise 3: Carbon cycle / Agriculture </p><p>NOTE: Part I of this assignment asks you to apply system concepts covered in lecture on Sept. 8 (stocks and flows, conservation of matter, time lags) to what you’ve learned about the carbon cycle. Part II of this assignment requires you to have done the assigned readings for the week of September 15, particularly Articles 8 and 20 in Annual Editions.</p><p>Part I The carbon cycle/systems thinking (40%) This question asks you to apply some systems thinking, through a hypothetical example. The first figure shows the stock of carbon dioxide in the atmosphere from 1950 to 2000. Let’s assume that in the year 2000, anthropogenic emissions of carbon dioxide dropped instantaneously to zero and remained there forever. (This is, of course, not what actually happened!) Assuming anthropogenic CO2 emissions followed this scenario, sketch the likely path (the continuation of the simulation) for atmosphere CO2 stock for the next 50 years to the right of the second figure. Note that you will have to draw on this page (unless you would like to copy the second graph onto a second piece of paper and then draw the figure, which is fine as well). No math is necessary to sketch the curve. </p><p>1 SKETCH THE CONTINUATION OF THIS CURVE GIVEN THE INPUT ABOVE:</p><p>Hints: (1) The terrestrial carbon sink is not constant; as atmospheric concentrations of CO2 decline, so will the absorption of CO2 by terrestrial biomass and soils. (2) There is a wide range of possible correct answers to this question. Given the complexity of feedbacks and uncertainties in carbon sinks (as exemplified by our discussion of the "missing carbon sink" in class), it is difficult to know exactly how the carbon cycle would respond to a change like the one proposed here. However, there are many responses that we know are impossible, simply based on basic principles like the conservation of matter. Thus, the best way to think about this problem is to eliminate all of the carbon dioxide responses that you know would be impossible. Any answer in the realm of possibility will be treated as correct.</p><p>Now that you have sketched the continuation of the trajectory of atmosphere CO 2, explain in a paragraph why the curve is shaped the way it is. Use concepts learned in lecture. </p><p>Part II Agriculture Question 1: Answer these questions based on Halweil’s article (Article 20), "Where have all the farmers gone?" (30%)</p><p>2 A. What forces and processes have led to the vertical integration of agriculture and the expansion of industrial farming? </p><p>B. What are at least two negative social consequences of the loss of family farms?</p><p>C. What are at least two negative environmental consequences of industrial agriculture?</p><p>D. What advantages does industrial farming have over family farming?</p><p>E. Should we as a society encourage (and subsidize) the family farm? Why or why not? If so, how? This answer should be one paragraph in length. </p><p>Question 2: These questions refer to article 8, "Factory farming in the developing world" (15%) For fun, you may also want to watch "The Meatrix": http://www.bancruelfarms.org/meatrix/</p><p>A. What does the term "factory farming" refer to?</p><p>B. What are two social and two environmental effects of factory farming?</p><p>C. What is the relationship between vertical integration and factory farming? </p><p>Question 3 (15%)</p><p>Where do you stand on the debate about genetically modified organisms and why? Explain and defend your position in one paragraph. </p><p>3</p>