Module: MeteorologyTopic : Causes Of Ocean Currents Syl.No: MA2008________________________________________________________________________

Objectives1. Describe the main current systems of the oceans.2. Explain the main causes of wind-drift, gradient, and complex currents.3. Explain how currents may be caused by the effect of evaporation, and of wind

blowing over a coastline.4. Explain the various methods of charting currents.

Reference1. Meteorology For Mariners2. Ocean Passages For The World

Study GuideObj. Topic Reference Guide1

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3

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Current systems

Wind-drift current

Gradient current

Complex current

Effect of evaporatn.

Wind blowing over coastline

1) Ch152)

1)Ch162)

1) Ch16

1) Ch16

1)Ch16p231

1)Ch162312)

What is the direction of the main circulation in the North and South Atlantic and Pacific Oceans?What is the circulation like in North Indian Ocean and China Sea during NE and SW monsoons?What is the circulation in the Southern Ocean?What are the names, locations, and directions of flow of the principal ocean currents of the world?What starts the surface water moving?What is effect of earth’s rotation on the movement?Ratio between speeds of wind and current caused?What time period required for steady state?How does the movement of the surface layer affect the sub-surface layers below?What causes a gradient current?How may a slope develop on the water surface?What is the effect of earth’s rotation?What is the wind effect on the surface flow?What is effect of surface flow on the lower layers?How is the gradient current effected?How else may a complex current develop?Use the Mediterranean Sea to illustrate:Why does surface water flow in from the Atlantic?What is the effect of earth’s rotation?What is the effect of the land configuration?Use the Benguela Current to illustrate:What is the direct effect of the wind?What is the indirect effect of the wind?What is the result of the direct & indirect currents?What other currents have this upwelling of water?

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Module: MeteorologyTopic : Causes Of Ocean Currents Syl.No: MA2008________________________________________________________________________

4 Vector mean

Predominant current

Current rose

1)Ch14 What does vector mean current mean?What does the vector mean value represent?What is the usefulness of the vector mean chart?What does the predominant current represent?How is the predominant direction obtained?How is the predominant speed obtained?What is constancy of the predominant current?What information does the current rose show?What determines the length of an arrow?What do the subdivisions on each arrow indicate?What is the difficulty in producing rose charts?

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