some physical reason as yet uAknoi'm, In general, however, all 

 areas in the ocean showed an increase in amplitude with an in- 

 crease of the mean depth of the therraocline, which agrees sub- 

 stantially with the tvro-layer theory. 



Such depth versus amplitude data may be used to devise an 

 empirical relationship which will be applicable to one particu- 

 lar place in the ocean. As mentioned before, appendix A pre- 

 sents a derivation of an expression for the amplitude of a wave 

 along the interface between two fluids using the linear two- 

 layer theory and taking into account both the rotation and the 

 spherical nature of the earth. This amplitude was found to be 



Ka 



C.=- 



R cos«^ 



ARcosi^ . q-gPiF ' KgPiF'A _ Kg Pz 

 hj Rx/jj;F \Ro-pj-F R/OgCOS' 



"iV 



A^R coS(^ ARcos<^/Kg/>iF'A ^ crgPiF Kg/>i 



X Ra-p^ F R X Ptt F R p_ cos <A 



(20) 



The nature of the terms is explained in appendix A. It will 

 be seen that many of the terms are functions of the latitude, 

 radius of the earth, and the wave length. If we may assume, 

 as Haurwitz did, a constant wave length for bhe semidiurnal 

 and diurnal waves, then all of these terms become constant for 

 a particular place. In addition, for deep water it is not 

 possible for hjj to change very much relative to hj, since it is 

 so much greater in magnitude. Since p^ for all practical purposes 

 may be considered constant, it is then possible to include both 

 the depth and density of the lower layer in the constant terms. 



53 



