(Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1988-08)
Lawrence, Wendy B.
A tomographic array is placed in a 2-layer, flat bottom, steady-wind driven quasi-geostrophic
circulation model to investigate whether the analysis of acoustic travel time changes can
detect large-scale barotropic oscillations. Time series of sea surface elevation and upper
and lower layer meridional currents are generated for comparison against a series of acoustic
travel times. The spectra of these time series exhibit a broad mesoscale peak near a
period of 40 days. The spectrum of the acoustic travel time contains a significant peak
due to a resonant barotropic oscillation with a period of 28.6 days which is not present in
the spectra of the point measurements. In this numerical model, basin-scale tomographic
measurements are a better method of sensing the large-scale resonant barotropic oscillations
than are conventional point measurements because the tomographic system attenuates the
"noise" from the mesoscale.