Measuring velocities is much more expensive and resource intensive than measuring surface to bottom temperature differences.  Long-term mooring data, > 4 years, was utilized to develop general relationships between the surface and bottom temperature difference and the baroclinic kinetic energy.  Total baroclinic energy for all frequencies in 10-day records follows the relation E_H = E_BT B dT^A where E_H represents the horizontal baroclinic spectral energy, E_BT is the horizontal barotropic spectral energy, dT is the upper ocean to bottom temperature difference, and A and B are coefficients.  Relationships were also developed for different frequency bands to identify the kinetic energy exchanges between frequencies and the energy going into the high frequencies available for dissipation.  These frequency bands were the diurnal, semidiurnal tides, harmonics (3-10 cpd), and the high frequencies (> 10 cpd).  The diurnal tides dominated the overall energy.  The coefficients, especially B, showed a latitude dependence, particularly for the semidiurnal tides.  The high frequency dependence was weak.  Barotropic energy showed no dependence on the temperature difference.  The relationships were limited to moorings in depths 60 m on the continental shelf and with temperature differences of at least 4^oC.  There was more energy at the deeper sites nearer the continental shelf break.  These relationships can be useful in predicting the horizontal baroclinic energy fields for these frequency ranges without deploying and maintaining expensive velocity observations and can also be used to estimate the horizontal baroclinic energy available for mixing in models.
 

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