Inertial oscillations in the Mediterranean
Perkins, Henry T.
MetadataShow full item record
Measurements of ocean currents were made by the author in the Western Mediterranean Sea at five depths for two months during early 1969. In terms of the dominant and persistent presence of inertial oscillations, circularly polarized currents having periods of a half pendulum day, the data are among the most striking ever collected. Two contemporary theories have been adapted for interpretation of this data. On the basis of a ray or short-wave-length theory, energy arriving at the observing site is found to fall into two categories, that making direct arrival from the, surface where it is assumed to have been generated, and that which undergoes one or more reflections. To the extent that the former dominates, it is found that the Algerian Coast about 130 km. to the south would cast a shadow to the north, the precise shape of which would be highly dependent on small variations in frequency. The nature of this frequency dependence implies a gradual increase in frequency with depth at the observing latitude. Although the data show a measurable shift (about 3%) towards higher frequencies, which is roughly the required amount, the lack of progressive frequency change with depth does not support the shadow hypothesis. In addition, the data is interpreted in terms of normal mode theory, where the nearby coast is seen to force a discrete modal structure to the solutions. The observed variation of current phase with depth indicates that a single internal mode dominates over a large portion of the data, while variations of both current amplitude and phase with depth are consistent this being the third internal vertical mode. Existence of a normal mode is also consistent with the long time, on the order of three weeks, for which the oscillations were observed to persist and with the dimensions of the Mediterranean Basin.
Submitted in partial fulfillment of the requirements of the degree of Doctor of Philosophy at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution June, 1970
Showing items related by title, author, creator and subject.
Development of a "genome-proxy" microarray for profiling marine microbial communities, and its application to a time series in Monterey Bay, California Rich, Virginia Isabel (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 2008-09)This thesis describes the development and application of a new tool for profiling marine microbial communities. Chapter 1 places the tool in the context of the range of methods used currently. Chapter 2 describes the ...
Fox-Kemper, Baylor (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 2003-06)Inertial terms dominate the single-gyre ocean model and prevent western-intensification when the viscosity is small. This occurs long before the oceanically-appropriate parameter range. It is demonstrated here that the ...
Brownawell, Bruce J. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1986-04)Polychlorinated biphenyls (PCBs) were used as model hydrophobic organic compounds (HOC) to study physical~chemical processes which affect the speciation and fate of HOC in coastal environments. The focus of this study ...