First, view the effects of heat-trapping pollution on Earth's temperature in 1750, the current year, and 2050. Your goal is to help decision-makers see how as the blanket of pollution becomes thicker, more heat is trapped, which causes the average global temperature to rise. In the simulation yellow photons (sunlight) are entering the atmosphere. Red photons (heat) are being released from the Earth's surface. Some red photons escape Earth's atmosphere, but others are trapped by the blanket of greenhouse gases.
Complete the following steps:
- 1. Look for sources of greenhouse gases shown in the simulation in 1750. Then look for sources visible in the present and in 2050, noting how they change and what happens to the thickness of the blanket of heat-trapping gases.
- 2. Note the impacts of heat-trapping pollution on Earth's temperature in each year. Note how many red photons are visible on the screen, the speed of temperature increase, and the final temperature.
Click on the microscope icon (on the right), which allows you to "zoom into" the blanket and view the action of the top three heat-trapping pollutants. Complete the following steps:
1. Select CO2. Observe how it responds to the sun's heat (red photons). What percent of red photons is it affected by (does it trap)? Repeat this exercise for CH4 and N2O.
2. Note of which molecules seem to be most and least frequently affected by infrared photons. The more powerful a greenhouse gas is, the more frequently it is affected.
Once you have completed the above steps, use your findings and the course's readings to complete the lab questions below.
- 1. Identify natural and human-made causes of climate change visible in the computer simulation. According to the computer model, how have sources of heat-trapping pollution changed from 1750 to today? How does the simulation predict they will change by 2050?
- 2. According to the computer model and your readings, which source(s) of heat-trapping pollution contribute the most to climate change? Explain.
- 3. Recalling your observations from the three time periods, how has the thickening blanket of heat-trapping pollution affected Earth's temperature between 1750 and today? How will the blanket and Earth's temperature look in 2050? Does the simulation predict that positive feedbacks will kick in by 2050 (e.g., does the temperature increase appear to be accelerating)? According to your readings, what might explain positive feedbacks?
- 4. Briefly describe three impacts of climate change on ecosystems and biodiversity. Cite examples from course readings.
- 5. Briefly describe three impacts of climate change on people - e.g., economic, health, safety, national security. Cite examples from course readings.