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Tides in the Mediterranean and Adjacent Seas 



1915, p. 147)]. The agreement thus reached between the theory and the 

 observations was already very good. But Sterneck (1919) has tried to have 

 theory and observations agree even better. He used forty cross-sections 

 and, according to the usual method, he calculated the co-oscillating tides and 

 the distribution of the amplitudes of the longitudinal oscillation for all the 

 semi-diurnal and diurnal components. He took into account the influence 

 of the tide-generating forces and he attempted to fulfil the boundary con- 

 ditions by assuming the coincidence with the amplitudes on certain stations 

 in the centre of the Adria. Figure 169 gives the distribution of amplitudes 

 for the M 2 and K x tide along the Adria. The full line represents the observed 

 values, the dashed line the theoretical values if only the co-oscillation tides, 

 the dot-dashed line the theoretical values when the co-oscillating and the 

 independent tides are considered. The latter distribution corresponds a little 

 better to the observed one; however, it is obvious that the co-oscillating tide 

 is the major influence. The theory places the nodal line exactly at the same 

 point as observed. The good agreement in phases and amplitudes leads to 

 the assumption that the frictional forces are negligible, which should be at- 

 tributed to the great depths of the central and southern sections of the Adria. 

 The diurnal tides do not show a nodal line; the tide consists in a rise and 

 fall coinciding with the external tide, whereas the amplitude increases slightly 

 towards the inner closed end of the canal, corresponding to the natural period 

 and the reduction of the cross-section. 



Fig. 170. Transverse oscillations in the Adria of the M 2 and K t tides caused by the Coriolis 

 force. For explanation of curves see Fig. 169. 



The Coriolis force acts upon the horizontal water displacements of the 

 longitudinal oscillations and causes transverse oscillations. These can be 

 calculated accurately but, if the phase and the amplitude of the theoretical 

 longitudinal wave are known, they can also be derived from the observations. 

 The comparison (Fig. 170) shows an entirely satisfactory agreement. It is 

 remarkable that the transverse oscillations in the southern part of the Adria 

 have a phase opposite to the phase of the transverse oscillation in the central 



