What's going on with the weather? Global climate change

Overview
This episode is intended to illustrate the complexity of an environmental issue and the interrelationships among the environment, energy use and economics. It starts with the development of basic scientific knowledge of the climate system and factors that can affect weather and expands to the interactions of environmental concerns over climate change with other societal needs such as energy supply and economic development.

Grade level rating:
Intermediate, Middle School, High School

Illustrative Instructional Objective Learners will work as contributing members of a collaborative group to formulate hypotheses about global climate change, participate in a debate, develop environmental impact statements for the next century, and realize that scientific investigation is always tentative and that new or more insightful investigations may alter previous understandings.

Background
Item: Some of the warmest years in the past 100 years have occurred during the 1980s and 1990s.

Item: January, 1996 saw one of the worst winter storms over the past 100 years in the Northeast U.S.

Item: The strongest hurricane on record for the Pacific Ocean skirts the coast of northern Mexico and sourthern Californinia in the fall of 1997.

Based on temperature data that extends back roughly 100 years, the 1980s and 1990s appear to include an unusual number of years with average global temperatures higher than normal. This, coupled with an apparent overall small warming trend in the 100-year record, has resulted in speculation that human activity may be altering the global climate. Complex computer models that attempt to predict such alterations suggest that the next century will see even greater warming as well as other consequences of a changed climate.

One of the notable features of the milder weather during the 1980s was a general lack of extended periods of severe winter weather. The winter of 1993-94 broke this pattern with a vengeance, with record low temperatures recorded throughout the Eastern U.S. during January and a series of severe winter storms that brought snow levels unseen since the mid-1970s. This extended period of severe winter weather followed a late winter East Coast storm in March 1993, referred to as "The Storm of the Century." Similarly, a record winter storm struck the Northeastern U.S. in January of 1996.

A strong Pacific hurricane travelled much further north than usual in the fall of 1997, passing near Baja California in Mexico and southern California, followed shortly after by a weaker hurricane that made landfall in Mexico and moved into the southwestern U.S.

What is the significance of the 100-year temperature record for predicting future climate patterns? Does the unusually severe winter of 1993-94 and 1996 suggest that the warming trend of the 1980s is over? Is an unusual pattern of hurricanes a manifestation of a changing climate? What is the distinction between long-term climate patterns and short-term weather anomalies? What is the possibility for such a climate change? What human activity is occurring that has the potential to impact the climate? What is the significance for changing or halting such activity? These questions and many more relate to the issue of global climate change and the ongoing debate over what action if any should be taken to avoid possible climate change.

Procedure
This episode is intended to illustrate the complexity of an environmental issue and the interrelationship among the environment, energy use and economics by starting with the development of basic scientific knowledge of the climate system and factors than can affect weather and expanding to the interactions on environmental concerns over climate change with other societal needs such as energy supply and economic development. The episode focuses on an exploration of core concepts of climate and weather, but allows for explorations into related areas of earth systems, energy use and alternative sources of energy, and economic development in the industrialized and developing countries of the world. The episode suggests opportunities to explore the following areas:

• Climate and weather
• Earth systems
• Energy: Current uses and alternative sources
• Economics/politics/government
• Conflicting results in scientific investigations

Activities related to this learning episode should be planned, implemented and evaluated jointly by the leader and learners. For example, learners should be responsible for preparing invitations for any outside speakers and developing questions to use with speakers, writing thank-you notes as appropriate, obtaining research materials from library or other sources, summarizing/graphing results of any weather measurements or data obtained from newspapers or others sources, and discussing in groups or with the entire class information developed during the episode and its relevance to the students.

Getting started
Use a brainstorming technique to generate questions and possible corresponding activities for areas such as the following. Sample questions and activities have been included as examples. Activities could be conducted individually or in groups. Different groups could focus on different topical areas.

The leader should serve as a facilitator and assist learners as they determine what areas to focus on and as they develop a list of results to be achieved. Through critical review and questions, the leader should guide the students to a broad evaluation of the topic or sub-topic.

Climate and weather
Possible questions:

• What is climate?
• What is weather?
• How are they related? How do they differ?
• What is temperature? How is it measured?
• What is precipitation? How is it measured?
• What things affect the weather and climate?
• How does the weather differ around the world?
• How has the climate changed in the past 100 years? 10,000 years? 1,000,000 years?
• What may have caused these changes?
• How might human activity affect the weather? Climate?
• What is a greenhouse?
• What are greenhouse gases?
• What greenhouse gases occur naturally? How do they affect the climate?
• What greenhouse gases result from human activities?
• What changes have occurred in greenhouse gas levels in the past?
• What changes in greenhouse gas levels are predicted for the future?
• How might these changes affect the climate?

Possible activities:

• Learn to use a thermometer to record temperature.
• Learn how temperature readings are affected by sunlight, shade, type of surface, etc. by taking readings in different locations in the classroom or outside.
• Check the daily newspaper to record changes in weather locally, statewide and nationally. Compare daily readings to normal values, if possible.
• Chart local temperature readings (daily average, high and low temperatures).
• Use newspapers and other media sources to review weather conditions in other parts of the world (The Weather Channel, on-line information services, etc.).
• Chart local temperature readings against readings from other parts of the world.
• Obtain information on long-term climate patterns from Ohio, U.S. and world.
• Construct a "greenhouse" (two-liter soda bottle model).
• Contact a local meteorologist for his/her views on climate issues.
• Invite them to the classroom for a discussion of climate and weather.
• Prepare questions for the discussion.

Earth Systems
Possible questions:

• What are the different systems that make up the Earth?
• How might the atmosphere, ocean and land systems interact?
• How might these interactions affect climate?
• How might the climate affect these systems?
• How might a change in the climate affect these systems?
• What steps could be taken to protect some systems if the climate changed?
• What is the carbon cycle?
• What are the natural sources of carbon dioxide?
• How does carbon move between different systems?
• How might human activities be affecting this cycle? Energy use? Deforestation?
• How does Earth differ from other planets in the solar system?

Possible activities:

• Prepare a poster illustrating the carbon cycle
• Identify activities by learners/families that might affect the carbon cycle
• Obtain and graph data on atmospheric levels of carbon dioxide for various time periods
• Discuss possible reason for changes in those levels
• Prepare a poster/paper comparing Earth, Mars and Venus and explaining why life is possible on Earth.

Energy uses and alternative energy sources
Possible questions:

• What energy sources are currently used in the U.S.? In Ohio?
• How do the learners use energy? How does the leader use energy?
• What energy sources are used in other countries?
• What are the benefits of energy?
• What are some of the impacts of energy? In U.S.? In other countries?
• How does energy use in the U.S. compare to other countries?
• What energy sources are used in other countries?
• What are the benefits of energy?
• What are some of the impacts of energy? In U.S.? In other countries?
• How does energy use in the U.S. compare to other countries?
• What are the implications of growth in energy use? In U.S.? In other countries?
• What energy sources are available for growth?
• What alternative energy sources are available? Solar? Wind? Trees?
• What are some of the current problems with these energy sources?
• What alternative energy sources might be available in the future?

Possible activities:

• Interview other members of the household on how they use energy and what it costs.
• Evaluate how an increase in energy costs might affect use. Explore ways that the household could use energy more efficiently.
• Prepare a poster illustrating how learners and their families use energy.
• Invite a representative from an energy company (electric utility, natural gas company, oil company, etc.) for a classroom discussion on energy sources. Prepare questions for discussion beforehand.
• Evaluate and debate relative benefits and impact of various energy sources (break into groups).

Economics/politics/government
Possible questions:

• How much does energy cost?
• How might an increase in energy costs affect the use of energy?
• What might the government do to affect the costs of energy?
• What might the government do to affect the sources of energy?
• What might the government do to affect the emissions of greenhouse gases?
• What is the government doing now?
• How might this affect Ohio?

Possible activities:

• Obtain information on what the U.S. is doing to limit greenhouse gas emissions.
• Evaluate how these actions might affect the state of Ohio and people living in Ohio.
• Obtain information on what other countries are doing to limit greenhouse gas emissions.
• Use on-line services to obtain views of other groups on climate change issue.
• Use on-line services to express views of the learners to others.

Accuracy and conflicting results in scientific investigation
Possible questions:

• How do scientists minimize bias, errors, and uncertainty?
• Do scientists always report their findings accurately?
• How do consumers of scientific investigations know that a study is reliable?
• Can scientists sometimes miss important information that might change their results and conclusions?
• How do scientists deal with results and conclusions from similar investigations which contradict each other?
• How do scientists balance the need to build upon well-established and accepted principles and the need to be open to ideas which are new, different or contradictory?

Possible activities:

• Evaluate investigations by scientists and/or learners for bias and accuracy.
• Find and discuss an article which reports on an investigator who in some way misrepresented results for conclusions from a study.
• Evaluate the reporting of scientific investigations in the media.
• Find examples of new information that calls into question long-accepted explanations.

Culminating activity:

Use a fishbowl technique to discuss and try to reach consensus on an overarching question such as "Is climate change occurring?" or "What changes should be made in human actions?" If different groups have focused on different areas, have one person from each group sit in a circle (the fishbowl) and discuss the question. The rest of the group observes the fishbowl discussion and are rotated into the fishbowl periodically.

Assessment:

A variety of ongoing assessment strategies should be used for learners and leaders to track progress. For example:

• Keep a journal detailing their activities, investigations and results.
• Teams of learners design "reports" that present their findings in multiple formats, for example, in pictorial, written and chart form.
• Fishbowl discussion with the leader and possible peer reviewers using a checklist to record participation and the quality of contributions.

Materials
Will vary according to activities chosen.

References
Greenhouse Effect and Global Warming, The. Enterprise for Education, Inc., Santa Monica, Ca., 1991.

Trends '91: A Compendium of Data on Global Change. Carbon Dioxide Information Analysis Center. Oak Ridge National Laboratory, December, 1991. (http://cdiac.ornl.gov/)

Heated Debate, The. Balling, Robert C., Pacific Research Institute, 1992.

World Climate Report (http://www.nhes.com/)

Unusual Weather - Not Necessarily Climate Change, Center for Ocean-Land-Atmospheric Studies, Calverton, Md. (http://www.iges.org/nncc/)