Further Work on the Kitaigorodskii Roughness Length Model: A New Derivation Using Lettau's Expression on Steep Waves

摘要

A model for the roughness of the sea surface is derived by a combination of two ideas: a) Kitaigorodskii's (1973) about wavelets being roughness elements that move with their associated phase speed; b) Lettau's (1969) about the roughness of a field of roughness elements with characteristic dimensions. The resulting sea surface roughness is related to a wave spectrum consisting of a Kitaigorodskii (1983) inertial form and a Phillips (1958) saturation form. The variation of roughness with wave age is discussed and related to the corresponding variation of the Phillips constant B.