several thousand miles in length in a single day, the data are not sufficient for preparation of 

 a regional chart such as the one shown in figure 14. Most of the ART data collected to date 

 have been used to supplement shipboard reports and other data sources. Sea surface tem- 

 perature patterns recorded by aerial survey have been used for analysis of data included in 

 regional charts. Over large areas where data are sparse and maximum coverage is desired, 

 a straight-line flight path also has been used. By flying perpendicular to major currents in 

 an area, positions of water masses can be checked for realignment of isotherms in correcting 

 sea surface temperature patterns. Straight-line flights of this type repeated on successive 

 days and spaced 30 to 60 miles apart have been planned often to cover an area progressively. 



More detailed coverage within short time periods is required for support of some 

 Fleet exercises and research projects. In such instances, a grid flight pattern is more 

 effective than the single straight-line track. The grid pattern is a series of flight tracks 

 spaced from 15 to 60 miles apart so as to produce maxim.um coverage of the given area. 

 Such grid patterns also can be flown on successive days to determine micromovement of sur- 

 face temperature patterns. The area covered by such a grid is necessarily small, but the 

 temperature field can be completely surveyed. 



SUMMARY 



Sea surface temperatures measured with the Barnes model 14-320 ART are subject 

 to environmental influences at the air-sea interface and at the aircraft. The instrument re- 

 sponds to acoustic vibration, shock, and turbulent air flow at or near the sensir^ unit. Noise 

 produced by these factors degrade measurement accuracy; however, such interference can 

 be reduced by proper mounting of the instrument in the aircraft. 



Comparison of the ART with standard surface temperature measuring methods suggest 

 that atmospheric conditions and the environment at the air-sea interface can have a pronounced 

 effect on the accuracy of the airborne radiation measurements. At low altitudes in fair 

 weather over a well mixed sea, infrared measurements of the sea surface have agreed (about 

 ±0.4°F) with standard measurements within the limits of accuracy of the system. At other 

 times, airborne infrared measurements have been 7°F lower than standard measurements. 

 Although biased by these outside influences, airborne radiation thermometry data reflect 

 surface gradients well. The primary value of aerial survey at this time appears to lie in de- 

 termination of gradient zones, rather than absolute temperatures. 



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