Week 3 Mapping Out Feedback Cycles Activity PDF

Preview

Summary

worksheet...

Description

Geol 115: Earth Systems and Climate Change Fall 2021

Name: Date: _______________

Mapping Out Feedback Cycles Activity Objective: Students will explore feedback cycles using information related to climate change, human activity, and wildfire. This activity is meant to reinforce concepts of feedback loops presented in lecture. Background  



Drought: a regional phenomenon linked to reduced rainfall and/or increased temperature. Fossil fuels: carbon-based resources (coal, oil, and gas) that are burned in order to produce heat energy, which generates power for electricity and transportation. Byproducts include carbon dioxide (CO2) and methane (CH4) gases, which are released to the atmosphere. Note: CO2 is also a byproduct of wildfires (burning vegetation releases stored carbon).

Figure 1. Drought map for the contiguous United States as of 9/2/2021. Drought intensity and impacts are shown in the legend to the right. Source: https://droughtmonitor.unl.edu/

Figure 2. Map of major wildfires (fire symbol) burning in the contiguous United States as of 9/8/2021. Blue dot indicates Harrisonburg, VA. Source: https://fire.airnow.gov/#

1

Geol 115: Earth Systems and Climate Change Fall 2021

Name: _______________ Date: _______________

Getting Started Compare the current drought map (Fig. 1) and the locations of active, major wildfires (Fig. 2). What climatic conditions are present in areas that contain major wildfires? (Hint: Refer to the legend in Fig. 1)

Part 1: Mapping a Feedback Loop The bulleted list below shows external forcings and internal interactions related to droughts in the western US.

List of external forcings and internal interactions  Drought [increases / decreases] in the western US  Greenhouse gas concentrations [increase / decrease]  Humans burn fossil fuels  Rainfall in the western US [increases / decreases]  Temperatures of Earth [increases / decreases]  Wildfire occurrence [increases / decreases] 1) Identify the likely external forcing(s) in this list (indicate by drawing a star). 2) Using the information provided above, diagram a plausible feedback loop related to droughts, climate, and wildfires in the western US. Draw your diagram on the next page of this activity. (Hint: examine the examples in Figure 3) 3) Interpret whether the feedback is a positive or negative feedback.

Figure 3. Examples of two different feedback loops.

2

Geol 115: Earth Systems and Climate Change Fall 2021

Name: _______________ Date: _______________

Draw the climate-fire feedback loop here:

This is a [ positive | negative ] feedback loop (circle the answer).

Part 2: Testing Your Understanding Are you certain that the feedback loop you drew is a (positive | negative) feedback? Test your knowledge by drawing an alternative feedback loop in the space below. However, in this scenario, invert the direction of change for each process that appeared in your feedback loop above (for example, if you began the first loop with greenhouse gas concentrations increasing, start this loop with greenhouse gas concentrations decreasing). You do not need to include an external driver for this feedback loop.

This is a [ positive | negative ] feedback loop (circle the answer).

Offer a possible external driver that could initiate this alternative scenario:

3...