The Ocean: Our Global Connector

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1 Check out: X15: Living Landscapes The Ocean: Our Global Connector - Standard #15: How physical systems affect human systems - The Power of Fire THE OCEAN: OUR GLOBAL CONNECTOR Overview: With over 70% of our planet covered with water, some historians have pondered why it was named "Earth" when in fact the name "Ocean" seems more fitting! Over the years, there have been various descriptors given to our watery surface: the "Seven Seas," conventional ocean divisions, and most recently, the Five Basins. In this lesson, through an exploration of the From Sea to Shining Sea map (PDF, Adobe Reader required), students will learn about these ocean descriptors, as well as come to understand that, although we have labels that separate names of different regions, the Earth ultimately has just one big ocean. They will explore how the currents of this one big ocean carry people, animals, and even debris around the globe. Students will study water movement and how tracking marine debris can be a way to learn more about currents and their impact on human activity. Connections to the Curriculum: Geography, social studies Connections to the National Geography Standards: Standard 1: "How to use maps and other geographic representations, tools, and technologies to acquire, process, and report information from a spatial perspective" Standard 15: "How physical systems affect human systems" Ocean Literacy: Essential Principles and Fundamental Concepts (PDF, Adobe Reader required) Principle 1: The Earth has one big ocean with many features National Science Education Standards Earth Science: Structure of the Earth System Time: One to two hours (longer if a review of plotting basic longitude and latitude points is necessary). Materials Required: From Sea to Shining Sea map (PDF, Adobe Reader required) Large wall map of the world Computer with Internet access Small-size Post-It notes to mark locations on map Student handouts or overhead transparencies of the Museum of Science Oceans Alive!: Looking at the Sea map Student copies of The Ocean: Our Global Connector Key

2 Vocabulary (PDF) Student copies of an outline map of the world with longitude and latitude labeled Objectives: Students will identify the Seven Seas and the Five Basins; describe how ocean currents affect how and where marine debris moves; identify Pacific Ocean currents; map the starting location where cargo was originally dumped into the ocean and track the movement of the debris; and describe the significance of ocean currents and how they affect humans. Geographic Skills: Asking Geographic Questions Acquiring Geographic Information Organizing Geographic Information Analyzing Geographic Information Opening: S u g g e s t e d P r o c e d u r e Guiding Question: How do the currents of Earth's one ocean impact humans? Begin by asking students what planets in our solar system have oceans. (Answer: Earth is the only one.) Ask them how much of our planet's surface they think is covered with water. (Answer: approximately 71%). Ask students to give a show of hands in response to the following question: Are the different oceans separated completely by land or is the Earth covered with a single layer of connecting water? (Answer: a single layer). Tell students that in this lesson, they will explore the different ways our one interconnected ocean has been labeled and discover the importance of the ocean currents that move all this water around the globe. Development: Activity 1: Getting to Know the Ocean Ask the students if they have ever heard the expression "to sail the Seven Seas." Select seven students to stand before a large wall map of the world. Explain that many years ago the "Seven Seas" may have been used to label the following (have each student locate one of the seas and stick a post-it note to mark it on the map): The Red Sea The Mediterranean Sea The Persian Gulf The Black Sea The Adriatic Sea The Caspian Sea The Indian Ocean Have the students step back to allow the class to see where the original "Seven Seas" fell. Ask the students if the Seven Seas are geographically far apart or relatively close together and why. (Answer: They are relatively close together, clustered around the Mediterranean, most likely because ancient mariners had not ventured far from that area.) Remove the sticky notes. Explain that in ancient times, "seven" also often meant "many," thus the expression "to sail the Seven Seas" may have simply meant to sail all over the world.

3 Later, the world's water was often divided into the following seven oceans: the North Atlantic, South Atlantic, North Pacific, South Pacific, Indian, Arctic, and Antarctic. Today our "water planet" is commonly broken down into four main oceans. (Note: Following the International Hydrographic Organization, National Geographic recognizes only four oceans: Arctic, Atlantic, Indian, and Pacific. Though the waters surrounding Antarctica are sometimes called the Antarctic Ocean or Southern Ocean, they are only the southernmost parts of the Indian, Pacific, and Atlantic Oceans. There is no Antarctic Ocean.) Ask five students to come up to the wall map to identify each ocean and mark it on the map as you read the following clues: This ocean is the largest ocean. It covers one-third of our planet's surface and is larger than the Earth's entire landmass. When Magellan sailed this ocean, he found it calmer than others he'd sailed and gave it a name which means "peaceful." (Answer: Pacific) This ocean is the third largest and includes the Red Sea and the Persian Gulf. (Answer: Indian) This ocean is the smallest and the shallowest. Much of it is ice most of the year. (Answer: Arctic) This ocean is the second largest and is the most heavily traveled. (Answer: Atlantic) Find the ocean that is closest to you. No matter how the oceans are labeled, they are all interconnected with water circulating all over the Earth. The vastness of the ocean can be illustrated by showing what our planet would look like if all the continents were shoved together, such as illustrated on this Museum of Science Oceans Alive!: Looking at the Sea map. (Note: This map may remind students of maps they have seen of Pangea the map of our world millions of years back. Point out that obviously the continents have moved over the years. Are they still moving? [Yes] How does this slow movement affect our oceans? [It changes the size of the oceans. For example, the Pacific is slowly shrinking and the Atlantic is slowly increasing due to the shifting continents.]) Activity 2: Getting to Know the Currents Next have the class examine the front of the From Sea to Shining Sea map (PDF, Adobe Reader required). Point out the identified currents (Kuroshio, North Equatorial, Subarctic, Alaska, and California). Explain that there are many named currents that do not appear on this map. Then ask the following questions: What are the general water movements called? (currents) What factors do you think affect these movements? (wind; water temperatures) Is there a general pattern of currents in the Northern Hemisphere versus the Southern Hemisphere? (yes, the North has primarily clockwise currents; the South has counterclockwise.) If you were on a cruise ship that sank off the coast of California, in which direction would your lifeboat most likely drift? (south) If tons of sewage and waste were dumped off the coast of the Mariana Islands, would it more likely reach Alaska or Hawaii? (Alaska, by floating along the Kuroshio current) You may also have students explore the interactive version of the From Sea to Shining Sea map and the related thematic pages online at the Marine Conservation Biology Institute's (MCBI) website. Next, have students read about oceanographer Curtis Ebbesmeyer, or tell them about his work. Much of his research is based on meticulous tracking of cargo that is spilled into the ocean. More than 100 million containers are shipped

4 across the ocean each year and each year more than 10,000 of them end up lost at sea, each containing anything from plastic turtles and rubber ducks to Nike shoes to Lego pieces. Ebbesmeyer and his small army of beachcombers plot the paths of floating trash and use such knowledge to map out ocean currents. One well-known spill was the 1990 Nike shoe spill in a North Pacific storm. Approximately 80,000 Nike shoes were washed overboard, each with an individual serial number that allowed Ebbesmeyer to follow where they washed up over the years. Ebbesmeyer has also traced rubber ducks that have floated from the Pacific to the North Atlantic. As a class, have students listen to an NPR interview of Ebbesmeyer entitled "Rubber Ducks Make Cross-Oceanic Voyage." Explain to students that research is also done by a number of other scientists to model ocean currents. You might want to show students some online animations of these predictive models, such as this NOAA oil trajectory prediction of how oil spilled from the Exxon Valdez in March 1989 would travel across Prince William Sound, Alaska, during the first week after that spill. More advanced students may want to explore modeling software, such as GNOME (General NOAA Oil Modeling Environment). Closing: Have students explore the implications of incidental current riding, such as that of the Nike shoes. Begin by asking students if they think it's reasonable to conclude that animals, plants, people and pollution can all use ocean currents as a mode of global transportation? What do they think are the implications of such current riding? Divide the class into seven groups, and assign each one of the following people who might benefit from studying ocean currents. Have student groups conduct research to help them consider why studying ocean currents might be of interest to their assigned person, and how the person's studies might be a benefit to society as a whole: (Note: provide groups with the thoughts in parenthesis as a start to their task.) A scientist who studies climate changes: (Since water currents carry warm and cold waters all over the world, they directly affect climate. Studying the patterns of currents can help scientists understand and better predict weather patterns.) A politician who makes laws regarding pollution: (If pollution is transported by ocean currents all over the globe, then one man's pollution is another man's problem. Knowing the patterns of currents can help track the point or origin for many pollutants that are detrimental to an ecosystem. Such information may hold political leaders more accountable or allow them to confront a foreign source of pollution that is affecting their nation.) A biologist: (Biologists can study biodiversity as organisms piggyback on or under floating debris and ride the currents to new destinations. They can also learn more about how these travelers affect the indigenous life of new habitats and ecosystems, as well as trace where the organism likely originated.) A business owner who ships materials overseas: (Businesses can map the best route since ocean currents can affect the speed and ease of travel. Businesses could also be better aware of where lost cargo would end up. This knowledge could reduce the overall cost of products as the most efficient route would cost less in terms of energy and time.) A person responsible for establishing shipping routes for oil tankers: (Not only would ocean currents affect the rate of travel, but the study of currents could assist the oil industry in recovering from any spills at sea. The oil industry consults scientists to learn more about ocean movement so that they can transport oil with the least risk and clean up most efficiently in the case of an oil spill.) An environmentalist: (Environmentalists can study currents to learn how devastating and far-reaching pollution is when

5 transported on the "conveyer-belt" of ocean currents. They note how moving pollution affects marine life and even creatures on land, since currents can carry non-biodegradable substances all over the world. Environmentalists are studying how a variety of toxic materials are distributed globally and analyzing the effects on plants and animals, including humans. Environmentalists can also use such information when studying the effects human behavior has on different ecosystems. The way a culture treats the environment does not simply affect the local area of origin.) A researcher studying waste disposal: (The study of ocean currents is of interest to these researchers because it offers much information about garbage and its longevity and potential for damage. They can study different products that do not break down after years in water and can learn how different areas in the world can better manage waste. Seeing garbage float from country to country over the years may also serve as an impetus to encourage the development of more and better eco-friendly products.) After student groups have researched and discussed the implications and benefits of their assigned person's study of ocean currents, have them prepare a presentation to make to the rest of the class. The presentations should focus on the value of studying ocean currents for their assigned industry or person, and should incorporate visual aids and/or demonstrations to emphasize their point. Following all the presentations, conduct a class discussion focusing on why studying ocean currents is of value to us as individuals. Guide students to consider how this knowledge might affect their personal behaviors, especially with regard to the environment and social and political activism. Suggested Student Assessment: Give students the following imaginary scenario: Your class has been given a billion dollars to put toward building a tourist space station or furthering oceanic research. Write a letter to convince the rest of the group to fund the latter proposal. Your letter should include facts and examples that underscore the significance of the ocean as an interconnected body of water that affects all life on earth. Use the following rubric to assess students on the completion of the letter: 4 = Student has demonstrated a thorough understanding of the following concepts, and offered examples to support his or her understanding: the interconnectedness of the oceans of the world the current patterns that connect the oceans the effect of human behaviors on the entire ocean, and therefore the global community 3 = Student has demonstrated a thorough understanding of two of the above concepts, and a partial understanding of the third, and offered examples to support his or her understanding 2 = Student has demonstrated a thorough understanding of one of the above concepts, and a partial understanding of the other two, and offered examples to support his or her understanding 1 = Student has demonstrated a partial understanding of all three of the above concepts 0 = Student has failed to demonstrate an understanding of any of the above concepts Extending the Lesson:

6 Inquiry Extension Use the Internet to research some of the other spills that occurred in the ocean, such as the mid-ocean Lego spill of 1997, the arsenic drum spill of 1991, and the rubber bath toy spill of Cross-Curricular Extension Read about how the floating plastic debris in the ocean has become a "commercial jetliner" for aquatic animals at "Ocean Litter Gives Alien Species an Easy Ride." Discuss the implications of transplanting species. (Science) Read about the Santa Barbara Oil Spill in 1969 (PDF, Adobe Reader required). Discuss the implications of that spill on how the United States and California State government have altered their thinking about how we take care of the marine environment since that time. The oil spill was thought to be one of the catalyzing events that lead to the establishment of the Channel Islands National Marine Sanctuary. (Social Studies) Try This at Home Read the article "Cousteau Finds Horrifying Trash on Desert Islands." Then go through your house and list all the different plastics products you use regularly. List ways in which you could reduce your use of plastic items. What can be recycled? Re-used? Are there alternative non-plastic products you could use instead? Make a list of changes you'd be willing to make to reduce your dependence on plastic. Share your list and reasons with your family. Participate in a local or regional beach or river sweep program that reminds us that trash and debris are damaging to both the marine and coastal environments and points out that our actions on shore even well inland impact the ocean and rivers. Check out the NOAA: Marine Debris Program. Then find a local or state group that organizes such programs. Take a virtual visit to the Northwestern Hawaiian Islands Marine Sanctuary and learn about the world's largest marine conservation area. Adaptations Students can work in pairs or small groups to compose the letter listed in the assessment. Related Links: College of Exploration Marine Conservation Biology Institute (MCBI): From Sea to Shining Sea NOAA: Getting to Know OSCURS, REFM's Ocean Surface Current Simulator NOAA: Marine Debris Program NOAA: Ocean Explorer National Geographic News: "Lost Sea Cargo Beach Bounty of Junk?" National Geographic: Oceans for Life EdNet Community Educator Resources National Geographic: Xpeditions Mapmaking Guide (grades 6 8) National Geographic: Xpeditions Sea to Shining Sea map ThankYouOcean.org: PSA The Museum of Science: Oceans Alive! Looking at the Sea This Page to a Friend

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