Earth's rotation affects flows in submarine channels

University of Toronto researchers Remo Cossu and Mathew Wells conducted laboratory experiments with a channel in a rotating tank to study the conditions under which Coriolis forces dominate the channel flow and to investigate how these forces affect sediment deposition in large-scale submarine channels.

They find that channels at high latitudes and those with large bends are dominated by Coriolis forces, while channels at lower latitudes and those with smaller, tighter bends are less influenced by Coriolis forces.

The researchers also show how Coriolis forces affect secondary circulation in successive bends of a sinuous channel. In Northern Hemisphere channels dominated by Coriolis forces, flow is directed toward the outer bank when the channel turns left and toward the inner bank when the channel turns right. In channels where the Coriolis force does not dominate, centrifugal forces direct flow toward the outer bank at all turns in the channel, regardless of the direction of the turn. These forces affect where sedimentation and erosion occur and contribute to the shape and levee asymmetry of the channel.

Their research appears in the journal Geophysical Research Letters.