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Title of Lesson: Ocean Currents Grade level / science course: High School Earth Science Big Idea of the lesson: Ocean Currents Lesson Objective: Given a globe, students will be able to draw and label the 5 main ocean gyres. Students will be able to list the 5 main gyres of the oceans. Students will be able to identify the effects on the oceans due to the coriolis effect. Students will be able to list the reasons for increased and decreased salinities in the oceans. Students will be able to describe the effects of currents on climate. Students will be able to list the positive effects of upwelling. Student Objective: You will label the 5 main ocean gyres on a globe. You will take a quiz on ocean currents at the end of class. Alignment with NC Standard Course of Study Competency Goal & Objective: Competency Goal 4: The learner will build an understanding of the hydrosphere and its interactions and influences on the lithosphere, the atmosphere, and environmental quality. Objective 4.02: Analyze mechanisms for generating ocean currents and upwelling: -Temperature -Coriolis effect -Climatic influence Required Materials (What and how much) Distribution of materials 10 Black globes (1 black globe will be distributed by the teacher to groups of 3 students) 20 (2 markers will be distributed by a student volunteer to groups of 3 students) 1 Clear pie plate with water, pepper, and 1 straw (for teacher demonstration) Media (software, overhead transparencies, video, etc) Equipment (computer, display, OHP, VCR, etc) Word document with input material (for student notes) Computer, Smart Board, White board, overhead projector Safety (Precautions and reminders) None, though students should be reminded that there should be no horseplay in the classroom. Time 10 min Presentation Outline Event Opener *NOTE: Students should be in assigned seats. Seats should be determined based on behavior and ability. Each group of students should be made up of different abilities. Written on board: Read page 545 in your textbook and write at least 3 bullet points of the main ideas from the article. Student volunteers should share their bullet points. Teacher should write their responses on the white board. Make sure the following is addressed regarding the article: -Track surface currents using drifting items. -Objects accidently become drift meters after falling off cargo ship. -Objects lost include athletic shoes and bathtub toys (rubber duckies). -Objects lost in North Pacific circulation. -Objects washed up in Alaska 6 months later. ASK: Have any of you heard of this before? Why should we care? 10 min Give them the statistics: 70 million bottles of water are consumed in the U.S. each day. In 2006, only 7% of plastic waste produced in the U.S. was recycled. Americans threw more than 22 billion plastic bottles in the trash in 2006. Have 2 student volunteers read the first 2 paragraphs of the following wikipage aloud. (Put wiki page up on the smart board). http://en.wikipedia.org/wiki/Great_Pacific_Garbage_Patch ASK: Who is in charge of cleaning up this mess? Where did this mess come from? Why should we care that it’s there? Do you know think there might be more garbage patches like this out there? What can we do to help? 10 min Input Word document *Make sure students are taking notes and explain to them that there will be a quiz at the end of the class period. Ocean currents- masses of ocean water that flow from one place to another. Why are they important? Currents help to recycle nutrients within the ocean. Currents and waves impact land and weather patterns. What produces ocean currents? Wind Density differences 2 Kinds of Circulation: Surface Deep-Ocean Surface Circulation: Surface currents- movements of water that flow horizontally in the upper part of the ocean’s surface. They develop from friction between the ocean and the wind that blows across its surface Gyres- huge circular-moving current systems that dominate the surfaces of the oceans and whirl within an ocean basin. 5 main ocean gyres: North Pacific South Pacific North Atlantic South Atlantic Indian Ocean 10 min Modeling Student Activity: Pass out black globes to groups of students. Have a student volunteer pass out markers. Instruction: Find the locations of the 5 main ocean gyres on your globes and draw dots on those locations. Draw the main gyres around the dots on your globes using arrows showing direction. 10 min After student groups have completed their gyres, the instructor should get the attention of the class and model the correct answers for the location and direction for the main gyres. Input Coriolis effect- the deflection of currents away from their original course as a result of Earth’s rotation. Because of Earth’s rotation, currents are deflected to the right in the Northern Hemisphere and to the left in the Southern Hemisphere. Each main gyre generally consists of 4 main currents. Ie- Norther Pacific Gyre consists of North Equatorial Current, Kuroshio Current, North Pacific Current, and the California Current. It takes a floating object (like the rubber duckie) about 6 years to complete a loop. Current impact on climate: (Ocean accounts for ¼ of Earth’s heat transport, wind transports the rest) -When currents from low-lattitude regions move into higher latitudes, they transfer heat from warmer to cooler areas on Earth. Example- Gulf stream. Anyone been deep-sea fishing? How far off our coast do you go? ~50 miles off Oregon Inlet. This impact on climate causes the U.K. and a lot of North-West Europe to have warmer winters than NYC. - As cold water currents travel toward the equator, they help moderate the warm temperatures of adjacent land areas. Example- Peru and western Africa. Upwelling- the rising of cold water from deeper layers to replace warmer surface water. (it’s wind induced) One type is called coastal upwelling- winds blow toward the equator and parallel to the coast- coastal winds + coriolis effect cause surface water to move away from the shore. As the surface layer moves away from the coast, it’s replaced by water that upwells from below the surface. Upwelling brings greater concentrations of dissolved nutrients, such as nitrates and phosphates, to the ocean surface. (supports marine productivity). 5 min Modeling Teacher Demonstration: Put clear pie plate filled with water on the overhead. Sprinkle pepper on the top of the water. Use the straw to blow over the middle of the pie plate. Have students observe that the water is rippled by the artificial wind and that the currents on the surface circulate around the edges of the pan. Point out that the wind created is analogous to the coriolis effect. Have students write down their observations in their notes and also draw a picture of the demonstration. 10 min Input Deep-Ocean circulation Density currents- vertical currents of ocean water that result from density difference among water masses. (Denser water sinks and slowly spreads out beneath the surface) An increase in sea-water density can be caused by a decrease in temperature or an increase in salinity. What increases salinity? Evaporation Formation of sea ice What decreases salinity? Melting of sea ice Precipitation Runoff from land High Latitudes- at the poles the surface water temperature decreases, then sinks due to its density, it then moves along the seafloor in slow currents. El Nino- At irregular intervals of three to seven years, these warm countercurrents become unusually strong and replace normally cold offshore waters with warm equatorial waters. Onset is marked by abnormal weather patterns that drastically affect economies (fish starve!) Too much rain. La Nina- When surface temperatures in the eastern Pacific are colder than average, a La Nina event is triggered that has a distinctive set of weather patterns. Colder air is blown over the Pacific NW and Great Plains while warmer much of the rest of the U.S. NC gets less rain. We are currently in the middle of an El Nino oscillation 10 min Check for Understanding The following discussion questions should be asked and discussed in small groups. After the class discusses in their small groups, the discussion should be extended to the entire class. Discussion Questions 1. During the 1700s, mail ships sailed back and forth between England and America. It was noted that it took the ships two weeks longer to go from England to America than to travel the same route from America to England. 2. How could sailors avoid the Gulf Stream when sailing to America? 3. You are in a sailing upwind in a regatta in Banks Channel off of Wrightsville Beach, NC. To the West of the sound you have a shallow bank that is only about 4 feet deep. On the east side of the sound you have a deep channel that is greater than 14 feet deep. The wind is equal throughout the channel and the incoming high tide is moving in a northerly direction up the sound. Where in the channel do you want to be sailing? 4. You are swimming on the beaches of Bald Head Island, NC. A hurricane is off the coast. When swimming, the local rip currents start to take you out to sea. What should you do? 15 min Closure The following quiz questions should be displayed in the word document on the smart board: Quiz: (Please answer on your own piece of paper and turn in) 1. Why do gyres in the Northern Hemisphere flow in the opposite direction of gyres in the Southern Hemisphere? Coriolis Effect 2. What increases salinity of the oceans? Freezing evaporation 3. What decreases salinity of the oceans? Precipitation Melting Runoff 4. What are the 5 main ocean gyres? N P, S P, N A, S A, I 5. Why are winters in the U.K. warmer than those in New York City even though the U.K. is a higher latitude than New York? Gulf Stream 6. How does upwelling affect marine organisms? Brings in greater concentrations of dissolved nutrients to the surface. Assign Independent Practice (Homework): Create a KIMP chart for 5 terms we discussed today in class. K- Term to know I- Information about the term M- Memory clue P- Picture Assessments Pre assessment: Based on the student answers to the discussion questions in the opener, the instructor will be able to get a feeling for what the students know about currents. Formative Assessments: The modeled gyre patterns on the black globes. Answers to student discussions. Student answers on the KIMP chart. Closure quiz. Reflection: Overall, I like the layout of this lesson. It’s easy to read and flows well. The use of the word document and smart board makes it so I wouldn’t have to be focused on the board the entire time, but could instead put up the word document and focus on explaining things and walking around the classroom. My concern with this lesson is the amount of notes that the students would need to take. Though I would assign that chapter’s reading the night before, I doubt students would actually take notes and retain a lot of the information. I tried to cut the notes down a little bit, but it still seems like a decent amount for a student to write down. However, I do think it’s very important for them to write it down to have to refer to later on when they’re studying. Also, by writing information down, they’re reinforcing that information. Even though this lesson uses direct instruction, I think the amount of input and the activities involved help to relay the information nicely. I don’t do any more than 10 minutes of input at a time and I involve activities and student-interest discussions as to keep their interest during class. The lesson also contains a lot of formative assessments that will allow me to figure out if my lesson is effective. I also really like my independent practice for this lesson. Its focus on literacy would be beneficial to students as a study tool. I think this lesson plan would be a thoughtful and effective lesson and I believe it would be simple to implement in the classroom.