Technology / Radar / Clear-Air Echos: Radar returns from cloud- and precipitation-free (optical clear) air. Clear-air echos are caused by bragg scatter and insects. Bragg scatter comes from small-scale fluctuations of the refractive index (i.e. Turbulent fluctuations of humidity).
Search Google for Clear-Air Echos:
Technology / Television (TV) / Echostar: The company that owns and operates DISH Network. MORE