MILES 

 24 



200 -- 



V^a'V 



_ll_U,JiL„., 



23° ISOTHERM 



lj«Cii!HCl^L>'- 



2000 

 HOURS 



Figure 3. Example of temperature data taken with the thermistor chain between 

 San Diego and Honolulu. 



OBSERVATIONS AND DATA 



Procedure 



The ship's course on Cruise 4 consisted of a great circle tow 

 between deep water off San Diego to deep water off Honolulu . The 

 chain was towed the entire distance and recorded temperature from 

 the surface to a maximum depth of about 750 feet at a speed of 6 

 knots. However, for one hour each day the ship's speed was in- 

 creased to 8 knots, and thus the towing depth decreased for this 

 period. 



The long, continuous section of isotherms constituted the 

 source of raw data. Inspection revealed that any given isotherm 

 became progressively deeper as the ship proceeded westward and 

 southward from the California coast. Also the surface water be- 

 came warmer and the vertical gradients were weaker toward 

 Hawaii. 



