The Ocean Basin Model encourages experiments with ocean surface circulation in a homogeneous, rectangular ocean basin, driven by surface winds, ocean bottom friction, horizontal pressure gradients and the Coriolis force. The rectangular image shown above represents the Atlantic Ocean above the equator.
The Ocean Basin Model is based on a model by Henry Stommel written about in "The Westward Intensification of Wind-Driven Ocean Currents from Transactions of the American Geophysical Union", Vol. 29, No. 2, 1948, pp 202-206. The model assumes a rectangular ocean basin.
The Stommel model is conceptually simple in comparison to present day models run on super computers. It is useful for the classroom as it allows users to investigate the processes that create strong ocean currents on the western boundary of ocean basins.
Investigations, located in the Teacher and Student Guides, will help students understand concepts of fluid dynamics and the behavior of fluids under varying conditions of:
Students will learn about the behavior of streamline function, characteristics of vortices and laws determining fluid motion.
Use this model to study the effects on the ocean basin of various parameters.
Ocean Size, Wind Stress, Basin Depth, Friction Force, Coriolis Force and Coriolis Force Variation with Latitude are all set to "Nominal" at start. Vary these above and below nominal to observe the effects of these parameters on the behavior of the model. The displayed image will update whenever adjustments are made to these settings.
The ocean size parameter allows for experimentation with ocean size and understanding what effects this has in the context of the model.
Wind stress is the frictional force exerted on the water surface by wind just above the surface. This force drives water around. The base value is 1 dyne/cm2.
Basin depth represents the overall depth of the water in the model. Baseline depth is 200 meters.
The dissipative friction force is a viscous friction between the surface mixed layer and the deeper ocean layers or the shallow continental shelf. This is needed in the model to dampen the motion and to prevent the water from continuously accelerating.
Coriolis acceleration is felt by objects set in motion over the surface of a rotating sphere, like the earth. This is similar to walking from the center to the outer rim on a merry-go-round while it is in motion, you feel off-balance. On a rotating sphere, rotation speed at the equator is fastest and speed at the poles is slowest.
Coriolis Force Variation with Latitude
This variation in the Coriolis force as an object tries to move between pole and equator. At different latitudes it will experience a speed difference as it travels which will affect the path of travel.
This open a new window displaying the existing model image.
These provide a readout of the current values for the different controlable parameters (to the right of the model display).
The image style control allows one to select from a series of different model display types:
The parameter control allows one to change the type of data presented from a series of types: