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1	Lecture 10: Ocean Circulation Ekman Transport Ekman Pumping Wind-Driven Circulation
2	Basic Ocean Structures Upper Ocean (~100 m) Shallow, warm upper layer where light is abundant and where most marine life can be found. Deep Ocean Cold, dark, deep ocean where plenty supplies of nutrients and carbon exist.
3	Basic Ocean Current Systems
4	Vertical Structure of Ocean
5	Mixed Layer Processes
6	Seasonal Variation of Mixed Layer
7	Two Circulation Systems
8	Global Surface Currents
9	Six Great Current Circuits in the World Ocean
10	Characteristics of the Gyres Currents are in geostropic balance Each gyre includes 4 current components: two boundary currents: western and eastern two transverse currents: easteward and westward Western boundary current (jet stream of ocean) the fast, deep, and narrow current moves warm water polarward (transport ~50 Sv or greater) Eastern boundary current the slow, shallow, and broad current moves cold water equatorward (transport ~ 10-15 Sv) Trade wind-driven current the moderately shallow and broad westward current (transport ~ 30 Sv) Westerly-driven current the wider and slower (than the trade wind-driven current) eastward current
11	Major Current Names Western Boundary Current Gulf Stream (in the North Atlantic) Kuroshio Current (in the North Pacific) Brazil Current (in the South Atlantic) Eastern Australian Current (in the South Pacific) Agulhas Current (in the Indian Ocean) Eastern Boundary Current Canary Current (in the North Atlantic) California Current (in the North Pacific) Benguela Current (in the South Atlantic) Peru Current (in the South Pacific) Western Australian Current (in the Indian Ocean)
12	Gulf Stream
13	Surface Current – Geostrophic Gyre Mixed Layer Currents controlled by frictional force + Coriolis force à wind-driven circulation à Ekman transport (horizontal direction) à convergence/divergence à downwelling/upwelling at the bottom of mixed layer Thermocline downwelling/upwelling in the mixed layer à pressure gradient force + Coriolis force à geostrophic current à Sverdrup transport (horizontal)
14	Step 1: Surface Winds
15	Winds and Surface Currents
16	Step 2: Ekman Layer (frictional force + Coriolis Force)
17	Ekman Spiral – A Result of Coriolis Force
18	Formula for Ekman Transport
19	How Deep is the Ekman Layer?
20	Ekman Transport
21	Step 3: Geostrophic Current (Pressure Gradient Force + Corioils Foce)
22	Ekman Transport à Convergence/Divergence
23	Geostrophic Current
24	Sverdrup Transport
25	Sverdrup Transport
26	Ekman and Sverdrup Transports
27	Conservation of Potential Vorticity
28	Boundary Currents
29	Step 4: Boundary Currents
30	Boundary Currents
31	Eastern Boundary Current
32	Costal Upwelling/Downwelling
33	Global Surface Currents