An Investigation Of Turbulence Driven Evaporative Duct Modeling

The suitability of using standard evaporative duct modeling for providing realistic refractivity profiles of the turbulent sea surface environment for interpreting X-Band wave reception observations recorded during the 2013 Tropical Air-Sea Propagation Study (TAPS13) experiment held near Lucinda, North Queensland is investigated. The TAPS13 experiment involved making meteorological parameter measurements required for refractivity profiling in coordination with operating (9, 17 and 35 GHz) transmit-receive links delivering wave reception measurements in the Australian Coral Sea. This is significant because the forecasting of radio wave propagation coverage depends upon realistic radio-refractive index profiling of the sea surface atmosphere and also on propagation models, such as the Parabolic Equation Method (PEM) models that can utilize accurate two or three dimensional refractive index information. The analysis presented here demonstrates that applying the logarithmic evaporative duct sea surface model representation to propagation modeling is insufficient in accounting for radio wave coverage duct during the intervals of study. This reality poses a challenge for radio-wave propagation forecasting schemes that depend on existing numerical weather prediction modeling for predicting refractive index structure.