A Changing Climate Globally and in the Great Lakes (Lesson 1)

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1 A Changing Climate Globally and in the Great Lakes (Lesson 1) Subject/ target grade: Science/High School (10 th Grade) Duration: 1 period for 55 minutes. Setting: Classroom. Materials and Equipment Needed: (All material found in CD-ROM provided with lesson) Per class Computer and LCD projector Keeling Curve and Tracking Climate Change (Interactive Presentation). Per student (or group of 3-4 students) Global and Great Lakes Climate Change Graph; provide a printed copy for each student (Procedure 2) Learning Objectives: Students will be able to: 1) Evaluate a data source to determine the accuracy, measurement error, and the logic of the experimental design (B1.1B.) 2) Explain climate change, describe the supportive data, and predict the potential effects on local ecosystems and biodiversity (B1.1f, B1.1e.). Michigan Content Expectations: B1.1g Based on empirical evidence, explain and critique the reasoning used to draw a scientific conclusion or explanation. Lesson Overview: Students will be introduced to the concepts of climate change, understand the scientific evidence, and evaluate how climate change has been monitored both globally and in the Great Lakes watershed. Lesson Core The Guiding Question: How a changing climate can be evaluated and predicted globally and in the Great Lakes. Safety precautions: None Advanced Preparation: Students will have received an introductory lesson on major concepts regarding climate change including the difference between weather, climate, the greenhouse effect, historic changes in climate, and anthropogenic effects increasing CO 2. They will have completed the interactive on-line assignments found in the Environmental Protection Agency s: A Student s Guide to Global Climate Change. x.html. Background Information for Teachers: Climate change is the long-term change in climate over hundreds to even millions of years. The earth has experienced many large changes in climate throughout its history, including large fluctuations in temperature and carbon dioxide (CO 2 ) (Figure 1). However none have likely been as rapid as what is being experienced today with the 1990 s being the warmest on record. The warming of the climate is expected to increase over the next half century due to CO 2 Ecology Unit A Changing Climate Lesson 1 1

2 and other greenhouse gases that are increasing in the atmosphere. Most climate scientists agree that the cause is predominantly due to humans magnifying the greenhouse effect where the atmosphere is trapping the heat from the earth to space. Many gases contribute to the greenhouse effect including CO 2 (an important component of our atmosphere). However, CO 2 levels have been steadily rising and this has been documented most notably by the famous Keeling Curve (Figure 1, see later information). CO 2 is released naturally through such activities as plant and animal respiration and volcanic eruptions. Human activities have increased CO 2 concentrations into the atmosphere by 1/3 since the industrial revolution including the burning of fossil fuels and oil. Figure 1. The Keeling Curve demonstrating increasing CO 2 levels and the seasonal annual cycle. An increasing climate has been documented in the Great Lakes region with high variability over the past few decades; this is especially evident because of the short time period of monitoring. The global increase has exhibited less variability due to buffering of the numerous sample locations and regional differences. Long-term and relatively short-term data sets are used when determining how the climate is changing. Scientists have estimated temperature and CO 2 levels extending up 400,000 years ago by analyzing core samples taken in the arctic (Petit et al. 1999). These data have been useful for determining historical climate change events and evaluating what we are observing currently. Short-term (<200 years) monitoring has been conducted extensively over hundreds of locations across the globe with one of the most notable being CO 2 sampling by Dr. Keeling since 1958 (Figure 1). The Keeling record of CO 2 is believed by some to be the most important time-series data set compiled for climate change research because it has correlated CO 2 levels with burning of fossil fuels. Great Lakes temperature has been monitored robustly since Important Terms: Keeling Curve: The observed increase in atmospheric CO 2 that has been precisely measured since 1956 by Dr. Charles Keeling. The data set is widely known as the Keeling Curve. Temperature Anomaly: The temperature deviation from what is considered normal. Anthropogenic impacts: Human impact on the environment. Climate variability: Long-term climate averages produced by significant annual climate variability. Procedure: 1. Use the example of the Keeling Curve for students to evaluate how climate data has been collected and interpreted. How do scientists collect and analyze climate data to determine changes in climatic conditions? Using the Keeling Curve and Tracking Climate Change teacher resource presentation the students will consider the story of Dr. Keeling and his collection of CO 2 data beginning in Teacher will describe why these data are believed to be some of the most important data ever collected for climate change research [First to measure an increase in CO 2, linked amount of CO 2 remaining in the atmosphere from fuel combustion, and documented that human produced CO 2 was not being absorbed fully by the ocean or vegetated areas on land]. Ecology Unit A Changing Climate Lesson 1 2

3 Discuss the importance of standardized data collection and how consecutive years of data with many data points are needed in making predictions. Teacher will describe how these data were collected in a standardized manner and why collecting data at the same location at set intervals is important. [Data sets are more robust and able to draw inferences from with an increasing sample size which is why the Keeling data contains numerous points per day and CO 2 levels are now collected at around 100 sites around the world. Larger data sets with more measurements are capable of still being useful with high variability]. Ask students why the Keeling monitoring station was placed at a remote area of Hawaii. [This collection location is above the atmosphere inversion layer where a temperature layer can hold pollution and other elements near the ground. This site is also at an inactive volcanic site that is isolated from human activities.] Have students describe the annual cycle of increasing and decreasing atmospheric carbon dioxide and identify the cause of these cycles and develop ideas on why the variability in the CO 2 levels have increased during the late 20 th century and early 21 st century. Show students the Vostok ice core data and have them explain if what we are observing now is a concern when we analyze the historic climate data [Large fluctuations have been observed in CO 2, temperature, and dust particles, however, the recent rate of change may place the globe into a warmer climate than ever observed. Climate change naturally occurs over long-term periods and anthropenic factors are a major factor currently]. 2. Impacts of a Changing Climate Assignment: Using the Global and Great Lakes Climate Change teacher resource presentation to show students how scientists determine that global and local temperatures are increasing. Display the global and Great Lakes temperature data set and the graphs which Temperature (C o )Anomaly climatologists use to evaluate climate change and theorize on future climate conditions (Figure 2). Have students describe what the labels represent and what the graph displays. [Xaxis: year, y-axis: annual temperature anomaly, data points: individual annual deviations from the mean reference temperature] Have students compare and describe similarities and differences between the global and Great Lakes temperature anomalies. [Probe students to identify the upward trend in temperature occurring in both data sets and the much higher variability in annual temperature anomalies for the Great Lakes data] Global Temperature Great Lakes Temperature Year Figure 2. Global and Great Lakes temperature anomalies that have shown a warming trend. Potential questions: What are reasons the Great Lakes data set has more variability? Would we expect to see more variability at a single region than the entire globe? [The global climate data has been collected at many more locations and has an averaging affect because it accounts for many geographic locations around the globe] How might collecting data at different locations affect the data? How would collecting data on land differ from those collected on water? Ecology Unit A Changing Climate Lesson 1 3

4 Should data collection sites be the same every year or different? What are the limitations of these two data sets and how might they be improved? Provide students with a graph of the combined data sets from the Keeling Curve and Climate Change Teacher Resource (same graph as found in figure 3). Ask them to predict temperature changes over the next 50 years and if inferences could be drawn on just a ten year section of the graph. Have the students use a colored pencil to draw a trend line to predicted changes to both the global and Great Lakes temperature data sets. The trend lines should be drawn on the right side of the graph (from year 2010 to 2060) with a straight edge. Students will then be selected to describe how they predicted temperature would change and how they arrived at their conclusion. Engage: Each activity will contain a classroom discussion about answers posed in the student activities. Climate change will be described in a global context but compared with trends that are also being observed and measured in the Great Lakes watershed. Building on prior knowledge: What are the main expected causes of climate change and what can be done to slow the predicted impacts? How do increased CO 2 levels influence the Greenhouse effect? Are certain populations of people throughout the world more impacted by threats of climate change? Which populations have the highest risk? What are the economic burdens associated with climate change by local and national governments? Pre-teaching: The teacher will give an introductory lesson on climate change that will include information about the Greenhouse effect, anthropogenic actions increasing causing climate change, and global issues that currently and may stem from climate change. Explore: This lesson not only explores topics related to climate change but also promotes discussion about the importance of longterm data sets in identifying and addressing biological issues. The Keeling Curve example introduces early work on atmospheric monitoring and provides an opportunity to explore the consequences of not collecting rigorous and sometimes unpopular data. This will allow for student to recognize and discuss how one (or a few) changes in the environment can have numerous interdependent outcomes. Explain: The learning objectives focus on evaluating the global climate change issues while preparing the students (in the next lesson) to predict changes to the Great Lakes watershed. In activity 2 they will work together in small groups and then a full classroom setting to evaluate how scientists predict climate change at both global and local scales, as well as, the similarities and differences in the data that are used. Because all students will be engaged on a single project that expands as more students input, the ideas they share will create a larger and more diverse outcome. To engage students there will be brief presentations prior to each activity so they will have the prior knowledge they need to work through each problem. Because both activities are making scientific predictions they will be encouraged to work together on predicting climate change, as well as, solutions to the predicted environmental problems that could occur. Elaboration: This lesson requires students to begin at a central concept (climate change) at a global Ecology Unit A Changing Climate Lesson 1 4

5 scale and work to a local understanding of the issue. Climate change may affect each ecosystem and the human community in unique ways. Global issues will be identified as well as those that are local (in the second lesson). Evaluate: During teacher presentation students will be asked to participate in identifying the importance of collecting long-term data and how to interpret these data when in graphical form. This will allow for the teacher to determine the class competency at critically interpreting data and potential problems that the students may have. Additional Resources: Information on The Keeling Curve : The Scripps CO 2 Program website provides information about Dr. Dave Keeling, the first person to make precision continuous measurements of CO 2 levels of the earth s atmosphere. Retrieved June 15, 2011 from A series of lesson plans designed to demonstrate the importance of understanding water resources and the impacts of global climate change. Retrieved June 15, 2011 from Lesson Closure (Shared between both climate change lessons): Why is climate change such a controversial subject to many people? What areas should we be focused on to slow the increasing temperature we are observing? How should the government be responding to climate change? In what ways can we reduce the risks of climate change? Lesson Extension References: Petit, J.R., J. Jouzel, D. Raynaud, N.I. Barkov, J.-M. Barnola, I. Basile, M. Benders, J. Chappellaz, M. Davis, G. Delayque, M. Delmotte, V.M. Kotlyakov, M. Legrand, V.Y. Lipenkov, C. Lorius, L. Pépin, C. Ritz, E. Saltzman, and M. Stievenard Climate and atmospheric history of the past 420,000 years from the Vostok ice core, Antarctica. Nature 399: Ecology Unit A Changing Climate Lesson 1 5