Study on evaporation duct model based on turbulent fluxes

Evaporation ducts are ubiquitous phenomena over the oceans, and they are responsible for much of the over-the-horizon propagation occurring with millimetre and microwave radars. The height of this duct is dependent on atmospheric variables and is a major input to microwave propagation prediction models. A theoretic method for computing the height of evaporation duct is proposed by using the parameter of turbulent fluxes. The height of the evaporation duct is given explicitly based on the evaporation duct existing in the marine surface layer´s constant flux layer and the formula of refractivity gradient when evaporation appears. The modelling results and the calculated results of evaporation duct heights with the other evaporation duct model show that the method is valid.