The center histograms show the distribution of differences for 

 observations taken in water depths greater than 100 fathoms and 

 the histograms on the right show the differences for observations 

 taken in water depths less than 100 fathoms. 



Figure 11 contains histograms of the differences between 

 observation and regression as a function of the percent of total 

 observations taken in water of less than 100 fathoms. 



An examination of the histograms, particularly those of 

 figure 11, leads to the not unexpected qualitative conclusion that 

 differences between regression and observation for the observa- 

 tions taken in water depths less than 100 fathoms are greater than 

 for those taken in deeper water. The conclusion suggests that 

 variables other than latitude, longitude, and day-of-year are im- 

 portant in determining the distribution of temperature in shallower 

 water. 



Fig-ure 12 shows the differences between the observed tem- 

 perature and that computed from regression as a function of day- 

 of-year for each of the three areas. In addition a two-standard- 

 deviation interval is shown on the right. From a seasonal point of 

 view the differences seem to be randomly distributed about zero 

 difference. However, for time periods of a few days to tens of 



50 



