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Education: Student Outcomes |
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Outcome: Explain how climate variations can induce changes in the global ocean circulation. | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Grade level: 9-12 Theme: climate Activity: http://www.tos.org/hands-on/teaching_phys_concepts.pdf
The purpose of this activity is to review basic concepts of thermal physics and highlight applications to ocean processes by focusing on the concept of convection. Convection and advection are the major modes of heat transfer in the ocean and atmosphere. Convection occurs only in fluids and involves vertical motion of fluid, or flow, rather than interactions at the molecular level. It results from differences in densities - hence buoyancy - of fluids. Examples of convective processes include: currents in Earth's mantle, which drive the tectonic system and result from heating and cooling of magma; atmospheric circulation resulting from uneven solar heating (e.g., between the poles and the equator); the global ocean conveyor belt and formation of deep water masses, resulting from cooling of surface water at high latitudes; and vertical mixing in the ocean's upper layer due to variations in heating between day and night. Advection usually refers to horizontal transfer of heat with the flow of water (e.g., the Gulf Stream). Read the following sections of Chapter 4 (Heat and Temperature) in preparation for this activity: • Background (p. 32) • Mechanisms of Heat Transfer (p. 33) Videos
Flash Video | QuickTime Movie
Grade level: 9-12 Theme: climate Video: keeping_up_carbon_03.flv
Researchers are learning that future climate change will depend on carbon levels in the land, in the atmosphere, and in the sea, and how these levels respond to human disturbance. About one-third of all human-generated carbon emissions has dissolved into the ocean. More than 80% of Earth's added heat is now stored in the ocean. Scott Doney: "In the future, as the planet gets warmer, the water's going to warm up, and warm water can hold less carbon than cold water - the other thing is, on a warmer planet, some of the currents are going to slow down, so we might not be forming as much of this cold deep water. So we won't be able to transport carbon into the deep sea. So on the whole, the ocean's going to become less effective at removing carbon from the atmosphere." (source) Grade level: 9-12 Theme: climate Video: keeping_up_carbon_04.flv
Stacey Boland: "As the ocean absorbs more carbon dioxide, it becomes more acidic, and this can be a threat to some of the organisms that live inside the ocean." As Earth's climate continues to change, how will researchers monitor something as big as the ocean, and something as complex as the carbon cycle? NASA Earth observing satellites give scientists the "big picture" view of our home planet. Varied satellites help researchers detect changes in ocean climate and ecology over time, providing vital insight into the health of our home planet. (source) Grade level: 9-12 Theme: climate Video: melting_ice_03.flv
Lora Koenig: "Even though the polar regions seem very far from a lot of people's day to day life, they are very important. Because they are regions that cool our earth. And as they change, they're going to cause larger changes throughout the rest of the globe." (source) Grade level: 9-12 Theme: climate Video: melting_ice_02.flv
Lora Koenig: "What we're seeing right now on the ice sheets and glaciers is that they are shrinking in size. And as glaciers on land are shrinking overall, that contributes a little bit to sea level rise. And we are worried that as we see warming over the ice sheets, and increased melting over the ice sheets, that they are going to start contributing much more to sea level rise." (source) Grade level: 9-12 Theme: climate Video: melting_ice_04.flv
Josh Willis: "As the great ice sheets in Antarctica and Greenland begin to melt and break up due to global warming, we really might experience very rapid sea level rise; three or four times as fast as the rate that we see today. So predicting this rate out into the future is very tricky because we really don't know when the ice sheets might break up and how fast they will when they do. So predicting future sea level rise is one of the great scientific problems of the future." (source) Grade level: 9-12 Theme: climate Tool: http://oceanmotion.org/html/resources/oscar.htm This data visualizer gives access to the following global ocean surface current behaviors between 1992 and 2008: current speed, current direction, current convergence, and current vorticity as well as the anomaly values for each. |