ORB-3 AND ORB-4 



The ORB-3 and ORB-4 measurements were made off the coast of Southern 

 California during December 1972 and February 1973 at the locations shown in figure 4 

 (references 8 and 9). The XBT measurements were all made from the Marine Physical 

 Laboratory research platform, the ORB. Measurements were made under tow at 5 knots 

 along the tracks shown in figure 4 and at anchor at the locations shown by the solid tri- 

 angles. The dashed line shows the surface location of a boundary between two different 

 near-surface water masses. All measurements during ORB-3 were simultaneous and were 

 made on two independent XBT systems. These systems are designated A and B in the 

 following discussion. The measurements provide data for a special relative accuracy study. 

 Table 3 lists, for each experiment and each XBT system used, the time interval, the number 

 of in-transit and at-anchor XBT profiles attempted , and the number of STD/SV profiles. 

 The STD/SV profiles were all made with Plessey Environmental Systems STD/SV sensors. 



Reference available to qualified requesters. 

 Reference available to qualified requesters. 



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