The Carbon Cycle and Its Effect on the Atmosphere

Transcription

1 The Carbon Cycle and Its Effect on the Atmosphere Name(s) Block Date FOCUS QUESTION: What is the carbon cycle and why should I worry about it? We are going to be learning about how the carbon cycle (which we discussed in ch. 19) causes changes in the Earth s atmosphere. Some of these changes are natural occurrences, while others are influenced by man s activities. Carbon cycles through many components of the world such as the atmosphere, biosphere, and hydrosphere. We are going to use a computer simulation to help us focus on how carbon not only goes through each of these, but influences changes in the atmosphere in particular. *To get to the simulation, go to the following website : SASCurriculumPathways.com Once you re there, LOG IN at the top of the page Username: rose53adjective password: ** Leave the password blank and hit ENTER! Click SCIENCE on the left; then choose ECOLOGY on the left to narrow the results Look at the list now and choose VLAB: CARBON CYCLE Click on that to start the simulation! Follow the TABS at the top and use this sheet to record your answers. Some of the directions will be found in the simulation so if you are looking for what to do next, check the site! It s all there! :-) TAB 1: Carbon Sources Read the questions below. Then complete this Journal by interacting with the online Simulation 1.1 ) Which carbon pools do you think are represented by the Simulation? In other words, where is carbon found? (3 places) 1.2 ) Observe the Simulation. What happens to the carbon contained in fossil fuel when that fuel is burned? a.) nothing b.) C goes into the ground c.) C goes into the air 1.3 ) Increase the burning of fossil fuel. What effect does this increase have on atmospheric levels of carbon? a.) C levels in the air rise b.) C levels in the water rise c.) nothing

2 1.4 ) The Simulation depicts a "closed system," which means that matter cannot enter or leave. Without clicking the Reset button, decrease the burning of fossil fuel. What happens to the level of atmospheric carbon? Why? 1.5 ) Click the Reset button. What effect does an increased level of deforestation have on atmospheric carbon? a.) more deforestation = less carbon in air b.) more deforestation = more carbon in air c.) no effect TAB 2: Life <--> Atmosphere In this section, you will examine the relationship between atmospheric carbon levels and living organisms, particularly trees and other green plants. ** In the Simulation (to the right) move the slider to the right or left to increase or decrease the level of atmospheric carbon. 2.1 ) Which carbon pools are represented by the Simulation? In other words, where is carbon found? (3 places) 2.2 ) Describe the ways in which carbon moves among these different pools. In other words, how does carbon moves between the 3 things you answered in question 2.1? 2.3 ) Which pool provides the carbon needed for photosynthesis? a.) atmosphere b.) water c.) plants 2.4 ) Increase the level of atmospheric carbon. What effect does increased atmospheric carbon have on photosynthesis? a.) Increased atmospheric carbon increases the rate of photosynthesis, which results in an increase in the amount of carbon stored in green plants. b.) Increased atmospheric carbon decreases the rate of photosynthesis, which results in an decrease in the amount of carbon stored in green plants. TAB 3: Ocean <--> Atmosphere In this section, you will explore the movement of carbon between atmospheric and ic pools and discover how changes in one pool can affect another.

3 ** In the Simulation (to the right) move the slider to the right or left to increase or decrease the level of atmospheric carbon. 3.1 ) Which carbon pools are represented by the Simulation? In other words, where is carbon found? (3 places) 3.2 ) Look at the three carbon gauges as you increase the level of atmospheric carbon. What happens to the levels of carbon in the surface and the when atmospheric carbon is increased? a.) Carbon levels in all 3 go up b.) Carbon levels in all 3 go down c.) Carbon levels only go up in the surface 3.3 ) Decrease the level of atmospheric carbon. What happens to the levels of carbon in the surface and the when atmospheric carbon is decreased? a.) Carbon levels in all 3 go up b.) Carbon levels in all 3 go down c.) carbon moves from the surface into the atmosphere thus increasing the C in the atmosphere and decreasing the levels in the surface 3.4 ) What is the process by which carbon moves among the atmospheric and ic pools? a.) osmosis b.) evaporation c.) diffusion TAB 4: Carbon Cycle 4.1 ) Data Collection In this section, you will examine the effects of human activities on the movement of carbon among all of the major pools. ** In the Simulation (to the right) use the sliders (panels A and B) to adjust the levels of fossil-fuel burning and deforestation. Click the Calculate Data button (panel C) to run an experiment. Then move the year slider (below the Calculate Data button) to examine the amount of carbon in each pool over time. NOTE: carbon amounts are listed in gigatons (Gtons). One Gton is equal to one billion tons. ** Use the Transfer Data button to record the initial carbon pool data from the Data panel to the tables before making any changes to the Simulation. Initial amount of Carbon in Each Pool atmosphere fossil fuel plants soil surface

4 4.2 ) Is the level of carbon the same throughout the or are there differences between different parts of the? a.) carbon levels are the same throughout b.) carbon levels are different in different parts of the 4.3 Data Collection Use the Transfer Data buttons to transfer the carbon pool data from the Data panel to the tables. Carry out the experiments as follows: Change the rates of fossil-fuel burning and deforestation, as indicated in the table. Click the Calculate Data button. Record the amount of carbon in each pool after years and years. ** Just to help you out, if the % change is (+), that means it is increased; if is (- )then % change is decreased; if is (0) then it stays the same! Experiment 1: A. burning of fossil fuel (% change per yr) = 0 B. deforestation (% change per yr) = 0 Experiment 2: A. burning of fossil fuel (% change per yr) = +3 B. deforestation (% change per yr) = ) Where does all of the carbon from the burning of fossil fuel end up? List all of the pools that increase as fossil fuel is burned. (should have 5 total!)

5 4.5 ) In Experiment 2, you increased the rate of fossil-fuel burning 3% each year. This is the current rate at which we are burning fossil fuels. Can humans continue to burn fossil fuels indefinitely? Use your data to tell when we will run out. Experiment 3: A. burning of fossil fuel (% change per yr) = 0 B. deforestation (% change per yr) = ) Which human activity has the greater effect on increasing atmospheric carbon in the short term (next years), fossil-fuel burning or deforestation? a.) fossil-fuel burning b.) deforestation 4.7 ) What about in the next years? a.) fossil-fuel burning b.) deforestation Experiment 4: A. burning of fossil fuel (% change per yr) = +3 B. deforestation (% change per yr) = +3 Experiment 5: A. burning of fossil fuel (% change per yr) = -3 B. deforestation (% change per yr) = 0

6 Experiment 6: A. burning of fossil fuel (% change per yr) = 0 B. deforestation (% change per yr) = -3 Experiment 7: A. burning of fossil fuel (% change per yr) = +3 B. deforestation (% change per yr) = -3 TAB 5: Carbon Cycle: Analysis Refer to the Journal, as needed, to answer the following questions. Carbon Sources A.1 ) Explain why the movement of fossil fuels from the the ground to the atmosphere has become significant only within the last 200 years. Life <--> Atmosphere A.3 ) Describe the two ways that deforestation increases atmospheric carbon.

7 Ocean <--> Atmosphere A.4 ) Can carbon move back and forth between the atmosphere and the? Explain. Carbon Cycle A.5 ) Explain one way that deforestation affects the carbon pools.