A simple physical model of the wind transformation on an abrupt change in surface roughness and temperature across a coastal line is suggested.
The model is based on a concept of the internal boundary layer (IBL) growth with fetch.
It consistently describes both small scale (order of 1 km) and mesoscale (order of 10-100 km) evolution of the IBL.
The planetary boundary layer problem (PBL) is solved using the similarity approach, which is applied for the IBL confined to the surface boundary layer, and the Ekman part of the PBL.
A 3-layer eddy-viscosity model of the PBL is introduced for the description of the mesoscale evolution of the IBL.
The PBL model takes into account the baroclinicity effects due to the temperature gradient across a coastal line. Dynamical coupling with waves is a model option.
The model is verified on existing data and a reasonable agreement with observations is obtained.
VN Kudryavtsev, VK Makin. Transformation of wind in the coastal zone