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North atlantic ocean: preliminary description of normal modes
Science (New York, N.Y.)
|October 13, 1972
Summary
Researchers estimated the North Atlantic Ocean's lowest gravitational free oscillation modes using numerical integration. The study identified three modes with periods of 21, 14, and 11 hours, revealing distinct amphidromic system structures.
Area of Science:
- Oceanography
- Geophysics
- Fluid Dynamics
Background:
- Understanding oceanic free oscillations is crucial for predicting tidal patterns and ocean dynamics.
- Previous studies have inferred tidal data but lacked detailed mode analysis for the North Atlantic.
Purpose of the Study:
- To estimate the three lowest gravitational modes of free oscillation in the North Atlantic Ocean.
- To characterize the periods and spatial structures of these oceanic modes.
Main Methods:
- Numerical integration of Laplace's tidal equations.
- Analysis of gravitational modes of free oscillation.
Main Results:
- Identified three modes with periods of approximately 21, 14, and 11 hours.
- Characterized mode structures with one, two, and three positive amphidromic systems, respectively.
- Phase distribution of the first mode aligns with diurnal tide cotidal charts.
Conclusions:
- The estimated modes provide new insights into the North Atlantic's free oscillation dynamics.
- The findings support previous inferences of tidal periods and enhance our understanding of oceanic tidal behavior.
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