15 - Effect of Earth's Rotation

Question 1

Rossby Number

Answer 1

This determines whether or not we can ignore Coriolis Force

Coriolis Force can be ignored in:

• Fluid flow
• Path of air around a wing
• Most rivers

R_o < 1 ; Consider the Coriolis force

R_o >> 1 ; Ignore the Coriolis force

Question 2

Geostrophic Flow

Answer 2

Concept focusing on: pressure force and Coriolis force

Assuming:

• Ocean currents are horizontal
• R₀ << 1
• Frictional forces are small

The pressure gradient and Coriolis forces determine most current flow in the ocean