For this lesson, you can select the parts that you’d like to do with your students. You can complete all of the investigations, or choose the activities you think would be most relevant to the climate change impacts where your students live. These experiments and investigations are designed to prime students for taking action in lesson 3 of this unit, as well as to critically think about the cause and effect of local impacts.
Continuing the discussion from Lesson 1, climate change can really be thought of in terms of energy transfer within systems. Students will have observed in Lesson 1 that increases in temperature (increase in thermal energy) affects rates of evaporation which in turn affects weather patterns. The focus on changes in energy transfer continues in this lesson.
In this lesson, students will only be examining small parts of systems to get a general understanding of why changes in precipitation may result in different impacts in different areas. Be sure that students understand that the relationships between factors within a system are complex and that any one area of the world may face a variety of climate change related impacts. Additionally, the more local the scale, the more difficult it may be to predict specific impacts.
For part 2, review the idea of wastewater treatment facilities and issues of runoff if necessary.
If you are concerned about space for part 3, you can either go outside to swing the psychrometers, or have one group go at a time. You may also wish to point out to students that the equation they are using is part of a mathematical model that weather forecasters use to make predictions.
For part 4, depending upon how wet the soil is to begin with, students may not need to add water. You should test the activity out with the soil and lamp you plan to use before doing it with students to get a sense of how much water should be added and how long the heat lamp needs to be in place before students will see results.
Relative humidity: The ratio between the amount of moisture in the air and the amount of moisture needed to saturate the air.
Stormwater runoff: Water from precipitation events that does not soak into the soil, but instead “runs” along land or manmade surfaces.
Psychrometer: A tool that uses the difference between readings of a wet bulb thermometer and a dry bulb thermometer to measure moisture content of the air.