Henry Charnock

Henry Charnock (25 December 1920 – 28 November 1997) was a British meteorologist. He is well known for his work on surface roughness and wind stress over water surfaces. The now named "Charnock's relationship" describes the aerodynamic roughness length, $$z_0$$, over a water surface by:

$$z_0=C u_*^2/g$$

where $$u_*$$ is the friction velocity and $$g$$ is the acceleration due to gravity (typically the Standard gravity). $$C$$ is Charnock's proportionality constant.

Charnock was President of the International Union of Geodesy and Geophysics (IUGG) from 1971 to 1975.