350 



OCEANOGRAPHIC INVESTIGATIONS 



DISCUSSION OF OCEANOGRAPHIC PROGRAM AND RESULTS 



General Environmental Parameters 



In order to provide general background data commonly needed in support of many phases 

 of the Sealab effort, a number of environmental sensors were maintained sample as often as 

 possible those factors which influences the under seaweather. These sensors, which included 

 both instrumentation provided by MDL and Scripps Institution of Oceanography, were located 

 as shown by Fig. 130. Wherever possible automatic sampling and recording instrumentation 

 were employed. These data were supplemented by measurements obtained by divers and ob- 

 servations from within Sealab. Listed below are those parameters which were monitored along 

 with a brief description of the instrumentation, methods employed and preliminary results. 

 Only MDL instrumentation and results are described; the Scripps program will be discussed 

 in Chapter 40. 



1. BENTHIC 



2. POWERHIVE 



3. WEATHER STATION 



4 MDL CURRENT METER NO. I AND THERMOGRAPH NO. I 



5. MDL CURRENT METER NO. 2 



6. VISIBILITY RANGE 



7. SIO WATER CLARITY METER 



Fig. 130. Location of Environmental sensors 

 and visibility range in sealab II area 



Temperature — The thermal characteristics of the water adjacent to Sealab were measured 

 by recording thermographs, a bathythermograph (BT), and a mercury stem thermometer. 



Three recording thermographs made by Braincon Corporation were used to record changes 

 in water temperatures as a function of time. These instruments are self-contained units which 

 record on 70-mm photographic film the position of the mercury column of a glass thermometer 

 with an accuracy of ±0.25 °C (0.45 °F). The film -advance mechanisms were adjusted to provide 

 a sampling interval of ten minutes. Two of the units were attached to Sealab, one was positioned 

 in the shark cage at the bottom, and the other was located on the catwalk some 6.1 meters (20 ft) 

 above the bottom. The third unit was positioned on the bottom at MPL current meter 1 some 

 27.4 meters (90 ft) from Sealab. The two units attached to Sealab were recovered, and the data 

 are presently being processed. Attempts to locate the third unit, which had been attached to a 



