Climate Change and the Greenhouse Effect
Objective
Big Idea
Day 1: Engage
I start the lesson by building and activating prior knowledge, writing the word climate on the board and asking students to try to define it by sketching a picture. After giving them a few minutes to complete their sketch, I ask for volunteers to explain what they drew and why, writing/paraphrasing their ideas on the board. Next, I have the students work with their table group to synthesize their ideas into a working definition of climate. (For example, one definition might be: "Climate is how weather acts over an area or region.") We share out each table's idea and allow each group to revise their definition as they see fit. Once each group feels they have an overall understanding and comprehensive definition of the term, they write it in marker on a piece of construction paper and leave it in the center of their table, to refer to throughout the lesson.
Next, I ask students to think about the phrase global climate. I ask them how global climate might differ from regional or local climate. After allowing them a few minutes to discuss with a shoulder partner, I explain to the students that global climate describes Earth's overall climate variability — such as average temperature, average precipitation, average intensity of winds, etc.
I show the TedEd video, "Climate Change: Earth's Giant Game of Tetris".
After watching the video, I provide the students with about 10 minutes to complete the Reflection Form. Once each student has completed the form, we conduct 2-3 rounds of Mix, Pair, Share to allow them to share their work with each other. I roam the room, listening to student conversations and assessing for understanding.
Adapted from the lesson, "Global Climate Change: Understanding the Greenhouse Effect" by PBS Learning Media.
Day 1: Explore
Next, I divide the class into small groups to begin exploring the effects of greenhouse gases on our atmosphere. For this investigation, I prefer to I assign roles as follows:
- Materials Manager: secures the proper quantities of equipment and materials necessary for each investigation and returns them at the end of the activity
- Clean-up Manager: makes sure each participant in the group is doing their part to clean up at the end of the activity and ensures that the area is left as it was when they arrives;takes responsibility for additional clean-up, such as wiping down tables, drying equipment, etc.
- Timekeeper: makes sure the group conducts their observations in equal time increments, records times that each part of the investigation was completed, and completes the activity in the time allotted
- Director: reads directions to all partners and makes sure they are followed accordingly; provides gentle reminder to keep all partners on task; speaks with the teacher if reminders are not successful
I have found that these roles provide every student with the opportunity to be fully engaged and accountable for the learning task. In addition, they ensure that the lab runs smoothly and the area is left clean and ready for the next group. It also fosters a sense of responsibility for the classroom, the activity, and meeting the learning objectives.
I pass out the Greenhouse Lab and have students complete the first activity. While the students are waiting for their temperatures to regulate, they use a laptop or other device to watch the The Greenhouse Effect video.
After watching the video, they discuss the questions given in their lab. Then, they collaboratively craft a response to each question. Students take turns to write the responses on the paper. Evidence of cooperative learning is demonstrated by all students' handwriting showing on the paper, signifying they each scribed the answer to a question as their group discussed it. I remind them that I'll be looking for evidence of "their writing". The lab questions are as follows:
- What is the greenhouse effect?
- What are four naturally occurring greenhouse gases?
- What are some man-made sources of greenhouse gases other than power plants and automobiles?
- What natural phenomena produce greenhouse gases?
- What would Earth be like without the greenhouse effect?
Day 2: Explain
After recording temperatures for 10 cycles, students graph their data in their lab guide. We discuss as a class, identifying patterns or trends, pointing out outliers and discussing possible reasons to explain their appearance and their significance to the investigation.
Day 2: Elaborate
After recording their temperature data, students complete the reflection questions in their lab guide. Students may discuss these with their lab partners in order to help make their claims and find evidence in their experiment to justify their reasoning.
However, each student should answer on their own paper. I allow students to share their thinking with a nose or shoulder partner and revise their responses as necessary.
Other questions that I might ask as I am circulating through the room include:
- How does increasing the amount of carbon dioxide in the atmosphere affect the global climate?
- If temperatures on earth rise due to increased greenhouse gases, how might human health be affected?
- If temperatures on earth rise due to increased greenhouse gases, how might different ecosystems be affected?
- Could increased temperatures on Earth be harmful for living organisms? Could it be helpful? How?
As one can see, I do not ask yes/no types of questions. I ask questions that make students stop to think and form responses, then answer using an explanation or description, rather than a simple yes/no or one word answer. By asking the questions above, I am also using a technique known as "stretching". Please see my reflection for more information!
Day 2: Evaluate
As an assessment of students understanding of the Greenhouse Effect and Climate Change, or as a possible extension to the lab activity, students work in pairs or small groups to explore the Greenland Ice Sheet Project 2: A Record of Climate Change Interactive to learn about the difficulties scientists face as they drill for ice cores in Greenland, and to find out what the scientists are learning about global climate change from the ice.
Students answer the following questions in their science notebooks:
- Analyze the Greenland Summit Temperature graph. Describe the two variables shown on this graph (temperature and time). During what time period did the largest change in temperature occur? Have we seen world average temperature changes occur this rapidly in the past century?
- Analyze the Methane Concentration graph. When did the largest change in methane gas concentration occur?
- Look at the Methane graph with the temperature overlay showing. What is the general relationship between methane concentration and temperature?
- Analyze the Calcium (Dust) graph. How does calcium dust get into the glacial ice? When did the largest change in calcium dust concentration occur?
- Look at the Calcium graph with the temperature overlay showing. What is the general relationship between calcium dust concentration and temperature? Why does this relationship even exist? (Hint: Think about reflected light.)
- Analyze the Insolation graph. When did the largest change in insolation occur?
- Look at the Insolation graph with the temperature overlay showing. What is the general relationship between insolation and temperature? What else besides the chemicals in the atmosphere affects the temperature on Earth?
- How might any of these variables (temperature, methane concentration, calcium dust concentration, and insolation) be used to determine past or future climatic conditions?
*This activity is not easy, as it requires a pretty advanced reading level and a lot of critical thinking as students analyze the wealth of information that is present. If you feel this is too difficult for your students, you can have them work with partners or groups, or you can simply use the lab reflection questions as the final assessment of learning. However, this activity is great for students who need more of a challenge or who show a particular interest in the topic.
