Climate Educator Guide, Activity 1: Climate Basics
The Earth’s climate is changing due to an increase of carbon dioxide (CO2) in the atmosphere. In this activity, students will explore the relationship between CO2 and climate by graphing changes in atmospheric CO2 over a 50-year period. They will also interview family members or neighbors to find out whether they have observed any climate changes in the area.
- Students understand that gases in the Earth’s atmosphere affect climate.
- Students will examine and analyze trends in CO2 levels.
- Students will learn how an increase in temperature can affect humans and ecosystems.
Beginning late in the 18th century, human activities have changed the composition of the atmosphere, influencing the Earth’s climate. This is known as global climate change.
What’s the difference between weather and climate?
Weather is what is happening outside at any particular moment in time. It may include daily or even hourly accounts of temperature, rainfall, cloud cover, humidity, and other variables.
In contrast, climate is what you might generally expect to happen based on long-term weather patterns. What is considered “normal” for the climate is often calculated using averages over a period of 30 years.
The Earth’s climate system is complex. It is affected not only by what happens in the atmosphere (the air), but also what happens on land, in the oceans, in forests and other ecosystems, and in glaciers and ice caps.
What is carbon dioxide (CO2)?
Carbon dioxide is a gas found in Earth’s atmosphere. Each carbon dioxide molecule is made up of one part carbon (C) and two parts oxygen (O), thus it is often written CO2.
What does CO2 have to do with climate?
One important element of global climate is the amount of so-called greenhouse gases in the atmosphere. These gases include CO2, nitrous oxide, methane, and water vapor.
Greenhouse gases, such as CO2, are a natural part of the atmosphere. In fact, they are necessary for life on Earth. Though they make up a small percentage of the Earth’s Atmosphere (see pie graph under the Activity Tab), they play an important role.
After the sun’s radiation enters the atmosphere and warms up the Earth, these gases prevent some of the heat from escaping back into space, similar to the way that the glass panes of a greenhouse can trap heat. Without this “greenhouse effect,” the planet would be too cold to support life as we know it.
Source: FAQ 1.3, Figure 1 An idealised model of the natural greenhouse effect. Climate Change 2007: The Physical Science Basis. International Panel on Climate Change. http://www.ipcc.ch/publications_and_data/ar4/wg1/en/faq-1-3.html
Why is the level of CO2 in the atmosphere a concern?
Levels of CO2 in the Earth’s atmosphere have been fairly stable for the past several thousand years at about 280 parts per million (ppm). Natural sources—like the decay of material in forests and grasslands—emit CO2 into the atmosphere. In the past, these sources were balanced by natural processes—like plant growth and the dissolving of CO2 in seawater—that removed CO2 from the atmosphere.
Around 1860, at the beginning of the Industrial Revolution, the CO2 levels began to rise. By 1958, CO2 levels were up to 316 ppm from 280 ppm. In 2010, they topped 390 ppm for the first time—a 39% increase since 1860. Scientists say this increase in CO2 is the main cause of rising global temperatures.
What has caused the increase in CO2 in the atmosphere?
Most of the increase in atmospheric CO2 is from burning fossil fuels for energy. These fuels include gasoline, kerosene and other petroleum products; coal; and natural gas. When they are burned, they release CO2, among other things.
Deforestation is another major source of CO2. When forests are logged for lumber, pulpwood, or fuel, and when new land is cleared for farming or pastures, CO2 is emitted into the atmosphere.
Why is it called climate change?
The rising average world temperature is often called global warming, but scientists prefer to use the term climate change. That is because its impacts will be different in every region of the world and will involve changes in rainfall and other climate conditions, not just temperatures.
- Copies of student pages (optional)
- Graph paper (optional)
Preparation: 10 minutes
Activity: Two to three 50-minute class periods
Write the data from the “Atmospheric CO2 Concentrations” [PDF] student page on the board, or make copies of it.
Doing the Activity
- Ask students whether they have heard the term, “global climate change”? Ask them what they think this term means. What does global mean? What is climate? Is climate the same as weather? What change might this term refer to? How is climate change different from “global warming?”
- Ask students whether their parents, grandparents or neighbors have ever mentioned any changes they have noticed in the climate. Invite students to interview someone in the community about changes they may have observed. They may use questions on the “Interview an Elder” [PDF] student page, adding their own if they would like.
- Have students share what they learned from the interviews. What changes have people noticed in the last 10-30 years? What might be causing these changes? How might these changes affect the community?
Ask students to name some of the gases found in air (nitrogen, oxygen, argon, carbon dioxide, water vapor, and rare gases such as helium, neon, and radon). Ask them what portion of air they think nitrogen, oxygen, argon, and carbon dioxide make up. (See the graph below. Air is about 78% nitrogen, 21% oxygen, 0.9% argon, and 0.03% carbon dioxide. The rare gases together make up about 0.07%.) Explain that students will be examining CO2 in the atmosphere over time to learn more about its relation to climate.
- Read aloud the introduction on the “Atmospheric CO2 Concentrations” [PDF] student page. Help students understand that 0.03% (the approximate portion of air that is CO2) is equal to 300 parts per million (ppm).
Divide the class into teams and assign each team a 5- to 10-year period to graph (there are 50 years of data). Direct the teams to create the x-axis (horizontal axis) and y-axis (vertical axis) so that the graphs will be uniform in scale. The x-axis should show the years and the y-axis should show values ranging from 310 to 400 ppm as in the following sample.
- Using the data for 1959 as an example, remind students how to plot a line graph. First they draw an imaginary vertical line from the place where the year 1959 would be on the x-axis, then an imaginary horizontal line from the place where 315.98 ppm would be on the y-axis. Where these two imaginary lines meet, they draw a point on the graph. To make a line graph, students will connect all the points after they plot them.
- Have the teams graph their data points and then connect the points. Post the graphs in chronological order, linking them along the x-axis to make one large graph.
Ask students to share with the whole group their observations about the graphs. Discuss:
- What pattern do you notice in the graph over 50 years?
- How do the last five years of data compare to the first five years?
- The level of CO2 in the year 1860 was approximately 280 ppm. How does the rise from 1860 to 1958 compare to that from 1958 to 2009?
- What do you think caused the increase in CO2?
- Looking at the graph, what do you predict the CO2 level will be in the year 2020? In the year 2050? What factors could influence these predictions?
- How might the change in CO2 affect people and other living things?
- Using information from the Background, help students understand the causes of CO2 change and the effects it may have for Guatemalans.
- Help students visualize the thickness of the Earth’s atmosphere by doing a simple demonstration. Using a piece of rope 13 meters long as a guide, help students stand in a 13-meter diameter circle. Have them stretch out their arms, holding hands if possible. Explain to them that if this circle represents the diameter of the Earth, the width of their arms represents the thickness of the atmosphere where the Earth’s greenhouse gases are found (the troposphere and the stratosphere layers). Are they surprised at the thinness of the atmosphere?
- Create a greenhouse effect using jars filled with equal amounts of water. Leave one jar open to the air, and cover the other jar with plastic. Put the jars in a sunny window and have students observe them over the course of the day or a week.
The Rainforest Alliance curriculum is unique in that it teaches science, math, language arts and social studies essentials while addressing the United States National Standards for Learning.
Science, Math, Social Studies, Language Arts
Analyzing, Determining Cause and Effects, Discussing, Identifying Relationships and Patterns, Researching
From PLT Conceptual Framework:
- Altering the environment affects all life forms, including humans, and the interrelationships that link them (2.2)
- When the Earth is studied as an interacting ecological system, every action, regardless of its scale, affects the biosphere in some way. (4.3)
- Ecosystems change over time through patterns of growth and succession. They are also affected by other phenomena such as disease, insects, fire, weather, climate, and human intervention. (5.4)
- Our increasing knowledge of the Earth’s ecosystems influences strategies used for resource management and environmental stewardship. (5.5)
Related PLT Activities
Waste Watchers (PreK-8 Guide), Energy Sleuths (PreK-8 Guide)
To assess their understanding of the relationship between CO2 and climate, ask students to write a paragraph describing what they learned from the graphing activity and the interviews.