Henry Charnock

Henry Charnock CBE FRS (25 December 1920 – 28 November 1997), often credited as H. Charnock, was a British meteorologist. He is well known for his work on surface roughness and wind stress over water surfaces. The now named "Charnok'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, shown to be 0.156.