Charnock's relation

From Glossary of Meteorology



Charnock's relation

An empirical expression for aerodynamic roughness length z0 = αcu*2/g over the ocean, where u* is the friction velocity, g is gravitational acceleration, and αc ≈ 0.015 is the Charnock parameter.

It accounts for increased roughness as wave heights grow due to increasing surface stress.


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