formule de Charnock

CONT: La formule de Charnock est utilisée pour faire évoluer la longueur de rugosité (uniquement sur océan libre) [...]

CONT: ... Charnock's formula for the atmospheric side makes physically much more sense than for the ocean side. For the atmosphere, one can imagine a wind blowing over roughness elements somehow related to the wave height. This is not quite correct, because waves are constantly moving and changing their shape, but it yields reasonable results. For the ocean side, however, you have breaking waves injecting turbulence into the ocean. So the length-scale of turbulence near the surface is more likely connected to the turbulence spectrum caused by the breaking events, rather than to the wave height. This implies that Charnock's formula lacks a clear physical interpretation. People use it mainly for the lack of better models.
CONT: Evaluation of LM [Lokal-Modell] wind speed forecast. ... offshore: Charnock formula (wind - wave interaction).
CONT: The water roughness model. ... The basis of the model is the well known formula of Charnock (1955) for surface roughness of the sea, stating that roughness increases with increasing wind speed.