Wind-driven Circulation

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Wind-driven Circulation Ekman layer Divergence/joining Geostrophy Major sea streams

Heat enters sea climate in tropics, goes out at posts

Winds on a NON-turning earth stream north-south

(Pinet)

(Pinet)

Major sea ebb and flow frameworks

Averaged worldwide sea geology from satellite perceptions

Coriolis Force (Mann and Lazier)

Coriolis constrain is an evident compel Coriolis constrain  2 · sin · u , where  is the Earth's revolution rate, i.e.,   2/86400 sec - 1 ,  is the scope, and u is the speed of the question Coriolis parameter f = 2 · sin Coriolis compel relies on upon scope and speed of particle

Northern half of the globe circumstance

Inertial Motion in Baltic Sea Inertial Period of 14 hours (time it takes to finish a circle) Inertial Period: T=2 /f Latitude =57.8 o N f = 2 · sin = 2 · (2/86400) · sin(57.8) = 1.23 x 10 - 4 sec - 1 Inertial Period = 2 /f = 14.18 hours In 7 days (15 tick marks) there are 11.8 inertial periods (check the intersections of the direction)

Wind Stress Direct impact of the wind does NOT reach out past the main 50-100 meters of the water segment

Vectors not collinear Vectors still not collinear Vectors collinear Wind drag + Water drag+ Coriolis = 0 Initially, the speed is toward the wind stress (or wind drag) But on the grounds that the powers are not adjusted the water moves to right of twist worry, until the vector expansion of powers is zero, at which time the speed is at 45 o to one side (in the Northern side of the equator) of the wind stress (or wind drag)

D E Ekman layer profundity D E 50-100m (Pinet)

Idealize the conditions in the red box...

The red box... Ekman Transport Westerlies Southward transport Northward transport Convergence Trades At the joining, water heaps up and sinks, in this way discouraging the thermocline and developing the nutricline! Ekman transport is corresponding to wind stretch  more prominent transport for more noteworthy wind push

Convergence (ocean surface heap up)

Sea surface Pressure inclination constrain Coriolis compel Velocity into page Geostrophic Balance Pressure slope drive adjusted by Coriolis constrain requires that the speed be into the page, along the weight lines , not crosswise over them (inverse to our every day experience of a "ball moving downhill").

Geostrophy – a frictionless harmony between the weight slope And the Coriolis speeding up – creates streams that move Around the "slope"

Measured normal geography of the North Atlantic (red-high)

Important focuses to take note of The ocean level heap up is a consequence of the joining of the Ekman transport The Ekman layer is ONLY 50-100 meters thick The subsequent weight angle is felt all through the water section Thus the geostrophic ebb and flow happens over a MUCH more noteworthy profundity than the profundity of the wind-driven layer, as much as the main 200 to 500 meters

(Pinet)

Major sea ebb and flow frameworks

Atlantic temperature and saltiness 500m Thicker warm water layer at 30 o N (likewise in Southern Hemisph.)