XBT 





°C 





Number of Differences 



Number 



n 



AT 



s 



Postive 



Zero 



Negative 



IN LAYER 















273L 



16 



-0.106 



0.02 











16 



274L 



16 



-0.077 



0.04 











16 



274aL 



Catastrophic failure 



- 



- 



- 



275L 



16 



0.013 



0.08 



9 



1 



6 



276L 



16 



-0.006 



0.06 



7 



2 



7 



277L 



16 



-0.162 



0.02 











16 



278L 



16 



-0.041 



0.04 







2 



14 



1 

 BELOW THERM OCLINE 



0.07 













273L 



5 



-0.130 



5 



274L 



5 



-0.012 



0.06 



3 







2 



274aL 



Catastrophic failure 



- 



- 



- 



275L 



[ 



Partial success 



- 



- 



- 



276L 



5 



0.052 



0.06 



4 







1 



277L 



5 



-0.136 



0.02 











5 



278L 



5 



-0.006 



0.08 



3 







2 



IN LAYER I 



slND below thermocline 













273L 



21 



-0.111 



0.04 



21 



274L 



21 



-0.061 



0.05 



3 







18 



274aL 



Catastrophic failure 



- 



- 



- 



275L 



16 



0.013 



0.08 



9 



1 



6 



276L 



21 



0.008 



0.06 



11 



2 



8 



277L 



21 



-0.156 



0.02 











21 



278L 



21 



-0.030 



0.05 



3 



2 



16 



Table 37. Summary of comparisons with thermistor chain measurements made 

 with vessel hove to and drifting. 



147 and 152 m. Figure 33 is a comparison of the two data sets. The "dots" are the 

 44 thermistor chain measurements superimposed on the XBT profile. If the XBT profile is 

 displaced in depth by +50 m, the two sets of measurements are in good agreement. This 

 suggests that the reason for this disagreement is that the recorder was not turned on until 

 the probe was at a depth of 50 m. The poor agreement between XBT and thermistor chain 

 temperatures is the result of operator error. This set of comparisons is not included in the 

 discussion to follow. 



The results of the comparisons of the remaining 63 profiles are summarized visually 

 in appendix E. One figure is presented for each acoustic run. The left portion of each 

 figure is a plot of the thermistor chain measurements. The symbol (x) is the average, and 

 the length of the bar is two standard deviations of the number of scans shown in the upper 

 left-hand corner. The "dots" in the right-hand figure are the differences between the XBT 

 and the thermistor chain measurements for each thermistor chain depth and for each XBT 

 profile made during the indicated run and in the indicated water mass or sound-speed profile 



84 



