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ary as compared to the open sea. Thus, though there is less area to cover in 

 the estuary as compared to the open sea, it must be covered in much less time 

 in order to obtain reasonably synoptic data. 



As a start toward obtaining recording buoy stations for shallow water 

 studies, the Chesapeake Bay Institute is now completing the adaptation of the 

 CTI into a five-depth buoy recorder for temperature and conductivity. At pres- 

 ent the device is designed to record each half hour for a period of ten days at 

 five depths between the surface and 150 feet. Also nearing completion is a cur- 

 rent meter which will record the magnitude and direction of the water motion 

 each half hour for a ten day period. This latter unit is designed especially for 

 inshore studies where fouling of moving parts of the conventional current meters 

 presents a problem. The CBI device has no moving parts, utilizing acoustical 

 means to obtain the water velocity. 



Dr. Fleming, in his comments on this subject, has warned against plac- 

 ing too much emphasis and effort on instrumentation as opposed to utilizing the 

 facilities we now have to increase our fragmentary knowledge of the oceans. 

 From my viewpoint the lack of suitable instruments remains one of the most, 

 critical factors in holding back our proper understanding of the physical phenom- 

 ena occurring in the ocean and the inshore areas bordering the ocean. Almost 

 every theoretical attempt to explain circulation or diffusion in the ocean or the 

 inshore waters requires for ultimate proof or disproof observations which can- 

 not be obtained with present facilities. 



One last comment on desirable instrumentation for shallow water studies 

 which may have general application in oceanography. Our knowledge of the 

 spectrum of turbulent motion in the ocean is almost completely lacking. The 

 possibility of observing this spectrum in the open sea appears sonmewhat remote, 

 since suitably securing the sensing elements would be almost impossible. Some 

 information might be obtained in shallow water through the use of towers se- 

 cured to the bottom, much as the turbulence in the lower layers of the atmos- 

 phere is studied. The tower, with suitable sensing elements attached, could be 

 constructed on a pontoon barge, which could then be towed to a suitable location, 

 the pontoons flooded, and the assembly sunk into position. When the operation 

 is completed, aqualung swimmers could be utilized to attach air hoses to the 

 pontoons and the assembly could be refloated, to be used in another location. 

 Measurements obtained from such an installation could be used to check the in- 

 direct deternninations of the non-advective flux of momentum and salt in estuar- 

 ies, and would be very valuable in the further development of flushing theories. 



