SEASAT Report,
Abstract
This report is concerned with the narrow V-shaped wakes seen behind surface ships by the SEASAT synthetic aperture radar. The authors do not believe that the V-shaped wakes seen by the SEASAT satellite are external waves because ship wakes are three to four orders of magnitude too weak to explain the observed radar returns. If the V-shaped wakes are not produced by internal waves, then by default they must be manifestations of the Kelvin wake. Present understanding of rear axis generation of Kelvin wakes ('thin ship theory') does not adequately explain the effects seen by SEASAT-non-linear effects probably need to be included. Also ships propeller-generated Kelvin wakes do not appear to be strong enough to create the wakes seen. Consequently, we are left with a somewhat unsatisfying situation. We believe that narrow wakes cannot be produced by ship generated internal waves, (except under extreme conditions) because these are too weak by three to four orders of magnitude. Therefore, they must be due to the Kelvin wake. But we have not yet been able to analyze the Kelvin wake sufficiently well theoretically to identify just which feature of the Kelvin wake SEASAT is seeing.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1985
- Accession Number
- ADA151283
Entities
People
- J. Vesecky
- K. Case
- K. Watson
- R. Dashen
- Walter Munk
Organizations
- MITRE Corporation