Ekman Number

Table of Contents

The Ekman Number is a dimensionless number used is geophysics to describe the relative balance of viscous forces to Coriolis forces in the fluid outer core.

ν is the kinematic viscosity of the fluid,
Ω is the angular velocity of the Earth,
r0 is the radius of the fluid core.

A typical value for the Earth is Ek ~ 10-9[1] .


  1. ^ Gubbins, D. (2007), Geodynamo, dimensional analysis and timescales, in Encyclopedia of Geomagnetism and Paleomagnetism, edited by D. Gubbins and E. Herrero-Bervera, pp. 297–300, Springer, Dordrecht.

See Also

List of Dimensionless Numbers