"c 



150 



HEAT-EXCHMGE COMPUTATIONS 



Data for the analyses of Figures 1 and 2 were obtained from ships, 

 located in the western Atlantic, which transmitted radio teletype reports 

 of synoptic weather observations to the U. S. Weather Bureau. The basic data 

 used were air and sea temperatures, dew point, and wind velocity. 



Jacobs' (19^2) final equations for the energy removed from the sea are 

 as follows: 



0^ = 145.1+ (e^ - e^^) Wa g cal/cm^ day 



Q^ = O.Ol(-t„ - t^) Qg g cal/cm^ day 



ew - ^a) 

 Q^ = Ik^.k (e„ - ea)+0.01 (t^- t^ ) W^ 



where 



a r energy used for evaporation 



= sensible heat exchanged between sea and atmosphere 

 through convection 



Qg^ = sum of Qg and Qc , representing total energy ex- 

 change between sea and atmosphere 



eg^ = vapor pressure at height a, in inches 



e = vapor pressure at sea surface, in inches 

 w 



Wg^ = Wind speed at height a, in knots 



t = sea surface temperature, in degrees F 

 w 



t = air temperature at height a, in degrees F 



Since in many previous studies computations for total eddy transfer of 

 heat have been averaged over large ocean areas (5- and 10-degree squares), 

 only generalized estimates can be made of the physical processes that may 

 exist; the resulting relationships therefore are incomplete. As pointed out 

 by Jacobs, the constants in the above equations are intended to apply only 

 to the marine climatic data which were used by him in his computations of 

 seasonal values over the oceans. Nevertheless, his constants have been 

 used subsequently in the more-or-less synoptic sense by a number of in- 

 vestigators; the results have almost invariably provided the proper order of 

 magnitude and have satisfied continuity, except when the constants were used 

 under conditions of extreme atmospheric instability. It should be pointed 

 out, however, that the validity of the constants has not been established 



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