# Absolute vorticity

From AMS Glossary

## absolute vorticity

The absolute vorticity vector is defined by 2Ω +**∇**×**u**, where Ω is the earth's angular velocity vector and**u**is the three-dimensional relative velocity vector.

- The vertical component η of the absolute vorticity vector (as defined above) given by the sum of the vertical component of the vorticity with respect to the earth (the relative vorticity) ζ and the vorticity of the earth (equal to the Coriolis parameter)
*f*: