Surface Hydrography 



The average surface temperature, salinity, and density (sigma-t) 

 in the quadrants of the main survey region are listed in table 2, together 

 with the extremes encountered. The distribution of these variables is 

 discussed below. 



Table 2. --Average surface temperatures, salinities, and densities in 

 the quadrants of the survey region, H. M. Smith cruise 20 



Temperature distribution 



The surface bucket temperatures obtained at each bathythermograph 



position are contoured on figure 12 at 0.5 F. intervals. The minimum 



o o 



tennperature of 71.8 F. south of 24 N. was measured at station 12 and 



the maximum of 76. 3 F. at station 56. Average temperatures showed 



no significant change from east to west on either side of the islcind chain. 



There were no outstanding features, such as centers of cold or 

 warm water, in the surface temperature distribution. A tongue of warm 

 water extended from the vicinity of stations 59 and 60 northeastward, 

 branching toward Molokai and Hawaii. Two other tongues of relatively 

 warm water extended northward north of Alenuihaha Channel toward sta- 

 tion 13 and north of Molokai toward station 24. 



In the exploratory section north of 24 N, the surface temperature 

 assumed a more regularly decreasing pattern toward the north. South of 

 26 N. temperatures tended to increase toward the west, whereas north 

 of this latitude they decreased toward the west. 



12 



