Intercomparisons of radiosondes and an airborne refractometer for measuring radio ducts

The capabilities of two types of radiosondes and an aircraft refractometer to measure radio ducting conditions were compared in a series of flights in September 1985 at Chatham, MA., on Cape Cod. The tests were part of a program studying radio propagation on Air Force communication links. The intercomparisons were made between data from a refractometer mounted on a small single engine aircraft (Cessna 172), data from an operational NWS synoptic sounding system. The synoptic sonde and the portable sonde were often on the same balloon train. The comparisons show that the aircraft refractometer data indicate the highest number of ducts and the synoptic data the least number of ducts. Keywords include: Atmospheric refraction, Radiosonde measurements, Refractometers, and Radio ducts.