Wave-tilt sounding of tropospheric ducts above the sea
Abstract
The possibility to detect tropospheric ducts above the sea through airborne wave-tilt measurements is investigated. Sea roughness and tropospheric refractivity anomalies associated with the presence of ducts are incorporated in an iterative procedure resulting in wave-tilt versus frequency diagrams at some altitude above sea level. In general, the diagram corresponding to ducting conditions appears sifted by delta f with respect to the diagram of the standard troposphere. This frequency shift is rather insensitive to variations of sea state, duct thickness, and optimum coupling height. It is though strongly dependent on duct intensity, delta M. The diagram of delta f vs. delta M is not far from linear in the VHF band and thus offering itself for delta M through delta f measurements.
- Publication:
-
In AGARD
- Pub Date:
- March 1988
- Bibcode:
- 1988sprm.agarS....C
- Keywords:
-
- Air Water Interactions;
- Ducts;
- Mathematical Models;
- Ocean Surface;
- Surface Roughness;
- Troposphere;
- Electromagnetic Radiation;
- Impedance;
- Ocean Currents;
- Polarization (Waves);
- Communications and Radar