Wind System over the North Atlantic 



81 



and we now integrate this equation from the surface 2 = to a height 

 z = h, where Tj. = ; hence Tq, the stress at the surface, is given by 



'"0=-/ p{Vg-v)dz. 



(3) 



The method has been used successfully to measure wind stress over the 

 land by a number of investigators, and over tropical seas by Sheppard and 



10 20 30 



WIND SPEED ( m./sec.) AT 10 m. ABOVE WATER LEVEL 



Fig. 51. Plot showing correlation of previous field values of shear stress 

 with model results. X = wind-tunnel results; S = Shoulejkin; P = Palmen; 

 E = Ekman; M = Montgomery ; R = Roll; B = Bruch; H = Hela; J = N. K. 

 Johnson; D = Durst; C = Corkan; L = Sutcliffe. Redrawn from Francis (1951, 

 fig. 9). 



Omar (1952). Sheppard, Charnock, and Francis (1952) have shown, from 

 a series of observations at the Scilly Islands, that this method does not 

 work well in the westerHes. 



Francis (1951) has given an interesting summary of the determination 



