Accession Number:

ADA091797

Title:

Ocean Internal Wave Induced Magnetic Fields Within a Submerged Buoy

Descriptive Note:

Final rept. Jan 1978-Jan 1979

Corporate Author:

INSTITUTE FOR DEFENSE ANALYSES ALEXANDRIA VA SCIENCE AND TECHNOLOGY DIV

Personal Author(s):

Report Date:

1980-05-01

Pagination or Media Count:

86.0

Abstract:

Ocean internal waves induce magnetic fields by virtue of motion of conducting sea water relative to the geomagnetic field. Measurements of such internal wave induced magnetic fields by sensitive magnetic instruments below the ocean surface require use of a protective enclosure or buoy. In this paper an analysis is presented of the effects of the enclosure on the magnetic fields and their spatial gradients when the enclosure buoy is spherical. Explicit analytical results are presented for the magnetic field and the magnetic field gradients for the case in which the sphere radius is small both in relation to the spatial period of the internal wave field and in relation to the depth at which the buoy is submerged. In addition, analytical results are presented for the temporal spectra of magnetic field gradients as these would be measured within the buoy when towed at speeds substantially greater than the maximum group velocity of the internal wave field.

Subject Categories:

  • Physical and Dynamic Oceanography
  • Electricity and Magnetism
  • Radiofrequency Wave Propagation

Distribution Statement:

APPROVED FOR PUBLIC RELEASE