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Evaporation ducts (ED), which are caused by a rapid decrease in the refractive index of the lower atmosphere, are known to trap radio waves between the evaporation duct layer and the sea surface. Although signal propagation and refractivity estimation in evaporation ducts have been well studied, the fading characteristics of ED must be accurately established to help determine fade margin, required for a reliable wireless communication link. In this paper, based on the percentage of occurrences of evaporation ducts, that have been measured and reported in the literature, the statistical distribution of path loss in the South China Sea is calculated for varying distances. These path loss distributions are weather-dependent and time-varying and define several slow time-varying fading characteristics. These slow fading characteristics are, what can be termed as log-lognormal in nature. Propagation in ED, being non …