APPENDIX II 
Moored Buoy Array Program 
1. THE SIGNALS TO BE READ ARE COMPLEX 
There is in the velocity, temperature, and salinity fields of the ocean 
a richness of unexplored phenomena. What the “water bottle” oceano- 
grapher regards as noise, or what he often dismisses as “internal 
waves,” “variability,” or “turbulence” is in fact a host of fluid dynam- 
ical processes. Far from being noise, these evidences of variability are 
actually signals which, could we read them, would tell us much about 
the internal dynamics of the ocean which we do not presently know. 
Present-day buoy technology provides means for exploring these 
new dimensions of oceanic phenomena. The actual use of moored in- 
struments has been limited to efforts of individuals who, lacking 
resources, logistic support, and necessary organization, have to date 
been unable to maintain a dense enough array of instruments for long 
enough time to gather statistically significant data. Signals are com- 
plex, and a sophisticated measuring program will be required to read 
them. This problem would be difficult enough if all fluctuations in 
deep oceans were due to a broad spectrum of linearly superposed in- 
ternal gravity waves of random phase plus some tidal lines. Even in 
such a hypothetical case many sensors would be necessary to separate 
vertical modes, and many horizontally spaced points would be neces- 
sary to discriminate wavelengths and to determine dispersion relations 
and directional properties. But all fluctuations in the oceans are not 
due to internal gravity waves; there are stirring motions, local insta- 
bilities generating turbulence and presumably exotic convective struc- 
tures due to the unstable salinity distribution. There will also be long- 
period eddies and Rossby waves, for example. 
2. DETECTION AND VERIFICATION OF INTERNAL GRAVITY 
WAVES AS AN EXAMPLE OF SIGNALS TO READ; FOUR- 
MINUTE SQUARE 
Among the many processes taking place simultaneosuly in oceans 
is the radiation of energy within the body of ocean water by means of 
internal gravity waves. It has a well-developed linear theory. 
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