Oceans and Climate 1-2 KEY CONCEPTS AND PROCESS SKILLS KEY VOCABULARY ACTIVITY OVERVIEW P L A Y R O L E E-85

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1 Oceans and Climate to minute sessions ACTIVITY OVERVIEW R O L E P L A Y Students learn more about how oceans affect climate. They participate in a role-play that discusses the history of the identification of the Gulf Stream and how modern technology is used to gather ocean data. An Intra-act literacy strategy helps guide discussion about the ideas presented in the role play. KEY CONCEPTS AND PROCESS SKILLS (with correlation to NSE 5 8 Content Standards) 1. Meteorologists, atmospheric scientists, climatologists, and hydrologists study different aspects of the earth s weather and atmosphere. Society relies on the information provided by such scientists. (History: 1) 2. Tracing the history of science demonstrates how individuals contributed to the development of modern scientific ideas, and reveals important interactions between science and society. (History: 3) 3. Factors that influence climate include the heating and cooling of land and water, ocean currents, latitude, elevation, landforms, and global wind currents. (Earth- Sci: 1) 4. Oceans have a major effect on climate, because water in the oceans holds a large amount of heat. (EarthSci: 1) KEY VOCABULARY climatologist Gulf Stream hydrologist ocean current E-85

2 Activity 57 Oceans and Climate MATERIALS AND ADVANCE PREPARATION For each student 1 Student Sheet 57.1, Intra-act Discussion: Oceans and Climate *Not supplied in kit TEACHING SUMMARY Getting Started 1. Introduce the role-play. Doing the Activity 2. Students participate in a role-play about ocean currents and climate. Follow-Up 3. (LITERACY) Students discuss the role-play using a literacy strategy known as Intraact.if this works) BACKGROUND INFORMATION Benjamin Franklin Benjamin Franklin was born in 1706 in Massachusetts, which at the time was an English colony. Even though his formal schooling was minimal, he became one of the most influential figures of his time in fields as diverse as science, literature, technology, government, business, and politics. He ran one of the largest printing companies in Philadelphia, and gained fame as editor and publisher of the Pennsylvania Gazette newspaper and Poor Richard s Almanack, an annual publication that had articles about things such as the year s planetary events, tides, and weather and was peppered with such adages as a penny saved is twopence clear (a penny saved is a penny earned). Franklin s curiosity about the natural world was limitless, and he investigated a wide range of phenomena from electricity to physiology. He was also fastidious about documenting his observations. In an era where the average person did not travel far from home, Franklin crossed the Atlantic eight times and visited 10 different countries. On his voyages to Europe, Franklin recorded both air and water temperatures of the Atlantic Ocean. His data was used to produce the first map of the Gulf Stream in the Atlantic Ocean. Franklin invented many tools that made daily life easier and safer. He invented the lightening rod, bifocal glasses, and an efficient stove (the Franklin stove) for heating houses. E-86

3 Oceans and Climate Activity 57 Franklin also participated in writing the Declaration of Independence, the peace treaty with France (1778), the peace treaty with Great Britain (1783), and the Constitution of the United States of America (1787). Because of this, Franklin is known as on one of America s founding fathers. He died in Philadelphia in Ocean Currents and Climate There are two types of ocean currents: surface and deepwater. Surface currents, which extend only to the first few hundred meters of the ocean, are primarily driven by wind and earth s rotation (the Coriolis effect), resulting in circular patterns known as gyres. In the Northern Hemisphere, the large, mid-latitude currents move clockwise while in the Southern Hemisphere they move counterclockwise. Deepwater ocean currents are also driven by differences in water temperature, salinity, and density. This movement of deepwater and surface water is known as thermohaline circulation. The interaction of surface and deepwater currents results in large-scale movement of ocean water around the globe sometimes called the ocean conveyer belt. The ocean conveyer belt results in the movement of water of different temperatures and salinity around the globe. Earth s oceans are heated by radiant energy from the sun and act as a heat reservoir, storing the absorbed energy. Ocean currents carry the stored energy around the globe by ocean currents. Climates are affected due to the interaction of this water, air, and land. A warm ocean surface current such as the Gulf Stream produces warm, moist air masses that can move into regions where they warm the climate. (Note that the portion of the Gulf Stream that crosses the Atlantic Ocean and nears the coast of the United Kingdom is sometimes referred to as the North Atlantic Drift. ) Ocean Technology In the past 50 years, satellite technology has expanded data-collection capabilities so that ocean-temperature measurements can be collected more rapidly than before. This data provides a clearer picture of monthly, seasonal, and yearly ocean changes, including temperature, sea-surface height, and current flow. In 1978, NASA launched the Scientists and Engineers Statistical Data System (SESTAT) satellite, which in only 105 days of operation collected more information about earth s oceans than in the previous 100 years of data collection from ships, buoys, and other drifting instruments. Currently NASA has several ocean-mapping missions collecting data from an array of bouys positioned around the globe, an effort that has made nautical maps far more accurate and greatly expanded knowledge of ocean currents. REFERENCES Bryden, H. L., Longworth, H. R., and Cunningham, S. A. (December 1, 2005). Slowing of the Atlantic meridional overturning circulation at 25 degrees North. Nature, 438: E-87

4 Activity 57 Oceans and Climate TEACHING SUGGESTIONS GETTING STARTED 1. Introduce the role-play. Explain to students that they will read aloud a roleplay in which all of the characters except one, Benjamin Franklin, are fictional. Ask, What do you know about Benjamin Franklin? Students may or may not be familiar with this historical figure, but they all will gain more from the role-play with some additional background information, which is provided in the Background Information section of this Teacher s Guide. DOING THE ACTIVITY 2. Students participate in a role-play about ocean currents and climate. Have students read the role-play aloud, either in small groups of four or as a class with an audience. Another option is to have students first read the role-play aloud in groups of four and then watch one (or more) groups perform it for the class. Many students are likely to understand and remember more ideas with a second reading. Often, students realize that they missed key ideas the first time through. FOLLOW-UP 3. (LITERACY) Students discuss the role play using a literacy strategy known as Intra-act. Intra-act is a literacy strategy intended to facilitate discussion and help students synthesize concepts. In this strategy, students evaluate statements related to the reading and decide if they agree or disagree with each one. Intra-act requires students to express an opinion about each statement. Their opinions should be supported by evidence or may sometimes rely on values related to evidence. Intra-act helps students think about what they know about the topic, and gives them a stake in participating in the discussion. Having to predict what others will say gives students an incentive to listen to each other and weigh differing perspectives. For more information on Intra-act, see the Literacy section of Teacher Resources II: Diverse Learners. Hand out Student Sheet 57.1, Intra-act Discussion: Oceans and Climate. Have students evaluate each statement independently and record whether they agree or disagree by circling Agree or Disagree next to each statement in the column titled Me. Students should enter the names of the other group members at the tops of the other columns and predict the opinions of their group members. In the next phase of this strategy, students score their student sheets as group members share their opinions. Each group member takes a turn revealing how he or she responded to the four statements and why, while the other group members compare their predictions to the actual response. On the student sheet, students mark whether their prediction was correct (+) or incorrect ( ) and count up how many of their 12 predictions were correct. The goal is to encourage careful listening and to have students share their opinions in a cooperative manner. As they do more Intra-act activities, students should get better at correctly predicting the opinions of members of their group. The scores they add up are not grades; from one activity to another they provide a measurement of students progress. Sample responses to the statements are shown below. Sample Responses to Student Sheet 57.1, Intra-act Discussion: Oceans and Climate 1. New technology is more helpful today than it was in the 1700s. Some students may agree, stating that technology today is more advanced and therefore more helpful than technology of the 1700s. Others may disagree and say that the technology developed in the 1700s was more helpful at the time because it was new. A third position that students may take is that it is impossible to evaluate, because technology from the 1700s was helpful then, just as today s technology is helpful now, but perhaps in different ways. 2. The greatest effect on climate is from ocean currents. Some students may agree because the focus of the role-play was on the interaction of oceans and climate. Other students may realize that E-88

5 Oceans and Climate Activity 57 there are many important factors contributing to climate, including energy from the sun and its heat stored in the oceans. Discussion of this statement is a way to review with students the importance of these other factors and to set the stage for the next activity, in which students read about other factors influencing climates. 3. Scientists have evidence that the Gulf Stream is slowing down. Students who disagree with this statement may say that there is no evidence to show that the Gulf Stream is slowing down and that the study referred to in the role play describes the slowing down of a cold deepwater current that is part of the global circulation pattern that includes the Gulf Stream, but does not provide data about the Gulf Stream itself. They may say that more data needs to be collected. Students who agree with the statement may say that data collected over a 50-year period provides evidence that the pattern of ocean currents, including the Gulf Stream, is slowing down. 4. All scientific ideas are discovered by experimentation. Many students may disagree and point out that an understanding of the Gulf Stream and ocean currents was developed through observation and data collection, not experimentation. A few students may agree, saying that a scientific idea is valid only if and when it has been reproduced through experimentation. Depending on students perspectives, you may want to use this statement to have a short discussion on the nature of science and scientific evidence. After students have completed their group discussions, discuss each of the four statements as a class. Be sure to review Statement 3, which helps assess students understanding of the ideas presented in the role play as well as the nature and scope of the scientific evidence presented in it. Use the Analysis Questions to summarize some of the key ideas presented in the role play. Analysis Question 3 serves as a QuickCheck to informally assess students understanding of the relationship between oceans and climate. There will be an additional opportunity to assess students understanding of this concept in Activity 58, Analysis Question 2. SUGGESTED ANSWERS TO QUESTIONS 1. What kinds of data do you think scientists need to collect to determine if the climate of Ireland is changing? Encourage students to think about different types of data that could be used to investigate this issue. Scientists can continue to collect additional data about the cold deepwater current, including water temperature and current speed, to determine if the current is continuing to slow down and at what rate. They could collect data on the Gulf Stream itself to determine if it appears to be slowing down. Or they might analyze years worth of mean air temperatures in Ireland to determine if there is any cooling of the climate. They could also gather historical geological data about the Gulf Stream and Ireland s climate. 2. How do the techniques used to map ocean currents today differ from those used in the late 1700s? Today, ocean current data is collected using instruments attached to buoys and satellites. The buoys are placed in oceans around the world by boat or plane. Instruments on the buoys gather temperature, speed, and salinity data which are then uploaded to satellites. Scientists can download the data for analysis. In the late 1700s, information had to be read from instruments that were dangled from boats. This process limited the amount and locations of data that could be collected. Modern techniques gather data more frequently and from more locations. The data can be made immediately available to scientists around the world. E-89

6 Activity 57 Oceans and Climate 3. What is the relationship between oceans and climate? A sample response is described below. When evaluating students responses, check to see if they have identified the following three ideas: 1) the sun heats earth s oceans; 2) oceans store large amounts of heat energy; 3) ocean water moves in currents that transfer some of this energy, affecting climates. The sun warms earth s oceans. Oceans store large amounts of heat energy and move that energy around earth in large currents. These currents transfer heat from one part of the world to another, affecting climates. The Gulf Stream is one example of a current that causes the climate of one part of the world to be different than it would otherwise be. 4. Look at the map below (in the Student Book). Describe the likely effect of the California current on the climate of California. Since the California Current is a cold current, it is likely to create lower temperatures along the California coast. This means that the climate of coastal California would be cooler than in other places of the same latitude (and altitude) that are not affected by such a current. E-90

7 Name Date Intra-act Discussion: Oceans and Climate 2006 The Regents of the University of California Names Me 1. New technology is more helpful today than it was in the 1700s. 2. The greatest effect on climate is from ocean currents. 3. Scientists have evidence that the Gulf Stream is slowing down. 4. All scientific ideas are discovered by experimentation. + : Predictions were correct. : Predictions were incorrect. Number of correct predictions: /12 Issues and Earth Science Student Sheet 57.1 E-91