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Scientist monitors resonant cavity equipment to 

 measure sound attenuation caused by plankton 

 organisms. Resonant cavity measurements 

 require the tower's stable platform and proximity 

 to fresh, live marine organisms. 



Data collected by means of the resonant cavity 

 chamber also show the relationship of oxygen 

 saturation of sea water to excess attenuation. 

 When the oxygen saturation is greater than 100 

 percent, the attenuation is markedly increased. 



60 



READING AT 



5 METERS 



A heavy bloom of Gonyaulax plankton ("red tide") 

 drifting through the resonant cavity suspended in the 

 sea caused excess sound attenuation of up to 64 dB/kyd. 



