III. Scripps Institution of Oceanography, Contract No, DA-li9-05^-eng-3, 

 Quarterly Progress Report No. 19, January to March 195ii 



Analysis of orbital velocity associated with wave motion in 

 shallow water is nearing conpletion. Agreement with solitary wave 

 theory is best near the bleaker zonej the field velocity tends to be 

 greater than theoretical velocity for long-period waves and less 

 for short- period waves. 



Continued measurements of sand-level changes show greatest 

 changes are taking place in shallow waterj at the deepest station 

 (70 feet) there have been no changes exceeding 0,05 feet. 



' A single device for accurately measuring the profile of large 

 ripples has been perfected. It consists of a series of parallel brass 

 prongs welded at right angles to a metal bar. The prongs are coated 

 with grease. When the device is forced into the sand bottom, the 

 iirprint of the ripple profile is clearly marked, A spirit level is 

 attached. 



The valley heads leading into Scripps Submarine Canyon have shown 

 a shoaling that amounts to as much as h feet in portions where the 

 slide took place during the previous quarter, 



IV, The Agricultural and l^chanical College of Texas, Contract No, 

 M-ti9--053-eng-18, Final Report 



This contract has now been conpleted except for the submission 

 of a report "Change in Wave Height Due to Bottom Friction, Percolation, 

 and Refraction" which is presently in preparation and essentially 

 completed. This project has studied the effect of shallow water 

 bottom conditions on the generation and propagation of waves in the 

 shallow water of the Gulf coast both theoretically and by field 

 studies. The results are largely contained in a series of three reports. 

 The first is that mentioned above, which makes use of the dissipation 

 functions presented by Putnam, and Patnam and Johnson, to obtain a 

 direct general solution of wave height transformation incorporating 

 the effect of refraction as well as friction and percolation; the 

 second, entitled "Generation of Wind Waves Over a Shallow Bottom" pre- 

 sents a numerical n^thod for determining shallow water wave generation 

 by successive approximations wherein wave energy is added due to wind 

 stress (as determined from the revised Sverdrup-Jtoik relations for deep 

 water generation) and subtracted due to bottom friction and percolation; 

 the third, "FLeld Investigation of Wave Energy Loss of Shallow Water 

 Ocean Waves", summarizes the field data gathered in the two years of the 

 contract and presents a tentative analysis of the effect of a non-rigid 



20. 



