These are due Monday, October 8^th at the beginning of class. Write your answers neatly and legibly on a separate piece of paper that you will turn in. You may need to access outside resources to completely answer the questions. Be prepared to discuss your answers with your study group.

1. A simulation model predicted that the world would become cooler and drier (p 38) if all the tropical rainforests were removed. However, we often hear that loss of the rainforest will speed global warming. Are both of these predictions true? Explain. Be sure to include the information in figure 3-10 in your answer.

2. As a result of agricultural and political processes, tropical rainforests are being converted to savanna in various parts of the world. Use the data on the bottom of page 36 to answer the following questions that illustrate the effects on the hydrologic cycle in the intact rainforest vs. the savanna.

1. After conversion to savanna, what percentage of the original leaf area coverage is left? Assume original forest was tropical closed forest.
2. A rainfall event of 3 cm occurred. Calculate the total volume and mass of the water that fell over 1 hectare. (assume the density of water at 1g/cm³, 1 ml = 1 cm³). Give your answer in liters and kilograms.
3. To compare the differences in the hydrologic cycle, let's look at the same 3-cm rainfall event on the two different ecosystems. Assume that the vegetation intercepts 2.57 x 10-1 cm of rain per m2 leaf area. How water reaches the soil under the tropical rainforest vs. the savanna?
4. Assume that the rate of evapotranspiration per unit leaf area for the savanna is only 70% of the rainforest. What percentage of the original potential evapotranspiration is left on a hectare after it is converted from rainforest to savanna?
5. What is the overall effect on the local hydrologic cycle of the conversion of the rainforest to savanna? List the changes that will occur in the groundwater, surface water, precipitation, and local climate.

3. Referring to the photograph on page 39, outline the consequences of increased urbanization of the Puget Sound on the local climate, nutrient cycles and hydrologic cycles.

4. What effects might global warming have here in the Pacific Northwest on the distribution of forest types, timber production, the local carbon cycle, and hydrologic cycle.

5. Clearcutting is a popular pastime for local and regional timber companies. What are some of the effects of clearcutting on the carbon, nitrogen, and hydrologic cycles?