A relation between the wind friction velocity and the sea surface microwave scattering

A simple recursive algorithm for the estimation of the friction velocity as a function of the air-sea temperature difference and the wind speed measured at 10 m height above the sea surface, without needing of drag coefficient, is presented. Numerical results are discussed in terms of atmospheric stability and compared to historical records of sea surface microwave backscattering. The friction velocity behavior, as a function of the temperature difference, with constant wind velocity, is found to be similar to that of the sea-surface microwave backscattering. This information implies a functional relationship between the surface wind stress and the sea-surface microwave backscattering.