Enter the  Main Exhibit Here Lessons Index: 1. MAP AND CHART 2. CHARTING THE GREAT WINDS 3. RIDING THE WIND 4. THE MAP CARTOUCHE 5. THE GULF STREAM 6. CHART MAKING FOR NAVIGATORS 7. HURRICANES 8. PROFILES 9. CHARTING NEPTUNE’S REALM 10. SURFACE CURRENTS 11. DENSITY CURRENTS 12. CURRENT AND CLIMATE 13. HUMAN INTERACTION 14. DEFINING THE EARTH 15. LATITUDE 16. LONGITUDE 17. COMPASS DEVIATION Osher Map Library University of Southern Maine

Charting Neptune's Realm: From Classical Mythology to Satellite Imagery An exhibition at the Osher Map Library and Smith Center for Cartographic Education, University of Southern Maine, Portland, 4 April 2000 to 11 January 2001 Donald S. Johnson, guest curator Lesson 12f - Glossary CURRENT AND CLIMATE Osher Map Library Lesson Charting Neptune's Realm Hope McVane A. Learning Objectives B. Background Information C. Teacher Activities D. Materials Required E. Presentation of Lesson F. Glossary Conveyor belt: the gyre of the Atlantic Ocean involving both surface and density currents. Thought to be a major component of reducing carbon in the atmosphere Density: mass divided by volume, mass per unit volume Density current: circulation of water due to differences in density El Niño: wind driven reversal of warm Pacific Equatorial currents, resulting in warmer water near the Americas Greenhouse gas: a gas that traps heat close to the earth, leading to a warmer earth and the greenhouse effect Gulf Stream: northern flowing warm water current Gyre: circular movement of water, larger than an eddy Salinity: measure of the quantity of dissolved salts in seawater; usually expressed as parts per thousand Surface currents: a horizontal movement of water; ocean currents caused by average atmospheric circulation (prevailing winds); influenced by Coriolis effect, landmasses, and other currents. Trade Winds: wind systems, which blow approximately 30° north and south toward the equator. Winds are northeasterly in the northern hemisphere and southeasterly in the southern hemisphere. Westerly Winds: wind systems blowing from the west between the latitudes of approximately 30° and 60°, north and south. They are southwesterly in the northern hemisphere and northwesterly in the southern hemisphere. I. Further Resources National Oceanic and Atmospheric Administration (NOAA) http://www.noaa.gov An Introduction to the Worlds Oceans, 4th edition Allyn & Alison Duxbury Wm. C. Brown Communications, INC IA 1984 Return to Lesson 12 Index Return to Charting Neptune's Realm index of lessons Return to Osher Map Library's complete list of lessons on the web