Teacher s Guide to Exploring Vertical and Horizontal Gradients for Air, Sea, Land and Ice

1. Teacher�s Guide to Exploring Vertical and Horizontal Gradients for Air, Sea, Land and Ice  Bill Capehart, Patty Crews, Nadina Duran-Hutchings, Jay Hutchings, Denyse Lemaire, Hieu Nguyen,and Alan Shapiro

2. Scope of Our Study Hydrosphere Atmosphere Solid Earth Cryosphere

3. Atmosphere Using first principles, derive the vertical behavior of pressure, temperature, and density of the troposphere (see Hydrostatic Tutorial.doc) How does the physical trend match the observations? To help answer this question use the real data we have compiled from Internet sources: Sample Instructor�s Back of the Envelope Worksheets.doc and the Readme file.

4. Atmosphere (Continued) How does the atmospheric boundary layer (the mixing layer) behave during the night and day? What physical processes come into play?

5. Additional Questions In the troposphere, what factors contribute to the temperature gradient? Do the same factors apply above the troposphere?

6. Graphs for the Atmosphere

7. Theory versus Data The idealized temperature and pressure profiles shown here can be derived by the student using materials and equations presented in the supplement document (Tutorial.doc)

8. Ocean Given the density of the oceanic profile, apply the hydrostatic equation to obtain the pressure profile in the ocean (see Hydrostatic Tutorial.doc) Again: How does the physical trend match the observation? Explain the local constant temperature and salinity within the ocean�s surface layers (middle latitudes). What physical processes come to play? What about the equator and poles? (Access the NOAA website for maps)

9. Graphs for Oceans

12. Upwelling/Downwelling in El Ni�o and La Ni�a Phenomena originates west of Ecuador and Peru, but effects are felt throughout the world; General prevailing wind circulation (South East Trades) forces surface water away from the coast; mass conservation requires a compensating upflow of water (cold) from the ocean bottom. Humboldt or Peru ocean current (South to North cold current);

13. Anomalous Conditions During El Ni�o and La Ni�a The ocean water is warmer during La Ni�a event along the west coast of South America; Comparison of temperature during an El Nino event; Horizontal surface winds reverse their direction, blowing primarily from the west during La Ni�a, forcing onshore flow of warm ocean water, and altering the Peru ocean current; During La Ni�a, upwelling is disrupted, warm water remains at and near the surface; Regional and global climates impact.

15. Compare the pressure vs altitude profile of the atmosphere with the depth vs pressure profile of the ocean. What properties do they have in common? What causes this effect? How are the mathematical relationships on the two graphs different?

16. Additional Questions Consider the temperature profiles of the solid earth and ocean, The temperature within the earth increases with depth. Is this an exponential or linear relationship? What causes this temperature change within the earth ? Does the ocean profile exhibit the same relationship? How is it the same? What causes the temperature of the oceans to decrease with depth?

17. Suggested Questions El Nino and La Nina are produced by changes in atmospheric pressure and ocean temperatures laterally from the west coast of South America to Eastern Asia and Australia. Vertical changes in temperature also occur in the oceanic and atmospheric column. Explain the observed horizontal temperature gradient in El Ni�o and La Ni�a conditions respectively. What changes in salinity occur with depth? Would you expect to see the same relationship along a line of longitude? What causes vertical changes in salinity? What could cause the horizontal changes both locally and regionally?

18. Solid Earth Study of the geothermal gradient; Depth versus pressure in the Earth (linear regression and data set); What is linear regression? Depth versus density; Depth versus S wave velocity; Depth versus P wave velocity;

19. Graphs for Solid Earth

22. Graphs for Solid Earth http://www.gcn.ou.edu/~jahern/vei/notes/seismo_interior/seismo_interior.html Lithosphere - Asthenosphere Boundary In the diagram below, the green line represents the temperature in the Earth as a function of depth. The yellow line represents the temperature at which mantle rocks just begin to melt; notice that pressure raises the melting temperature of mantle rocks. Between about 100 and 250 km depth, the "geotherm" grazes the "mantle solidus;" this is where the mantle is softest and may even be partially molten in some areas.

23. Additional Questions Changes in seismic wave velocity have been used to delineate the boundaries of the layers within the earth. Can you approximate the locations of these boundaries based on seismic wave velocity?

24. Cryosphere Interpret changes of density with depth Does the temperature variation follow the same pattern as the atmosphere or ocean

25. Graphs for Cryosphere

26. Integrating Observation for the Solid Earth Abrupt changes in seismic velocity occur from one layer to the other; Temperature increases from the surface to the core Pressure increases throughout

27. Additional Questions Compare the temperature gradient within the cryosphere with the solid earth�s geothermal gradient. In both spheres, the temperature increases with depth. What contributes to the temperature changes within these spheres. Does the same effect occur in the oceans? What causes the ocean temperature gradient?

28. Data Exploration Sites http://www.nodc.noaa.gov/GTSPP/gtspp-rt.html http://raob.fsl.noaa.gov http://132.156.108.210/personalpages/roddick/mantle_e.htm