neutral stability turbulent transfer coefficients for the 

 effect of atmospheric stability. Turbulent exchange pro- 

 cesses at OWS-V were calculated using Deardorff s method 

 with a neutral condition C j, of 0.0013 referenced to the 

 10-m level of observations (Appendix III). Ch and Ce were 

 assumed equal to Cp, for neutral conditions. Neutral 

 conditions were assumed when the absolute value of the 

 air-sea temperature difference was less than 1°C. The 

 1956-70 monthly mean Q(E)s values calculated by this 

 method are listed in Table 3 along with Q(E),g values 

 calculated with a constant Cq of 0.0013 and mean daily 

 meteorological properties. 



It is seen in Table 3 that the relative differences between 

 the two methods are smallest during July and August. 

 Although, on average, the relative difference between Q{E)^ 

 and Q(E)g ranges from 6 to 15%, for individual months the 

 difference may be as large as 30%. The use of Deardorffs 

 formulae shows that the effect of atmospheric stability on 

 the turbulent transfer processes at OWS-V can be 

 significant. The stability effect is not necessarily as large 

 over other portions of the ocean as at OWS-V. For example, 

 at OWS-N in the eastern North Pacific, the effect was less 

 than 5% (Dorman, Paulson, and Quinn 1974). 



Heat Exchange Processes Computed from DaUy 

 vs. Monthly Mean Meteorological Properties 



Heat exchange processes over the oceans have general- 

 ly been computed from monthly estimates of meteorological 

 properties because in most areas daily values are not 



available. For the sake of comparability and because 

 OWS-V is to serve as a reference station for the 

 computation of heat exchange processes from merchant 

 vessel data, we have used monthly mean meteorological 

 properties. 



In Table 4, the 1956-70 monthly values of the heat 

 exchange processes computed from the mean daily and 

 mean monthly meteorological properties and using a 

 constant C j, are listed. Evidently the differences are smaU 

 and well within the uncertainties of the determinations 

 discussed earlier. Seckel (1970) used a variable C^ to 

 calculate the evaporation rate over the central Pacific 

 Ocean. Comparisons showed that the evaporation rate near 

 OWS-N was an average of 28% higher when computed 

 from daily properties than when monthly properties were 

 used. 



Wind Stress 



The wind stress climatology for OWS-V is presented in 

 Figure 11. From April through November the resultant 

 stress is small in magnitude and variable in direction. 

 Components less than 0.28 dynes cm"^ were not plotted. 

 From December through March the resultant stress is 

 predominantly directed eastward with the largest magni- 

 tudes occurring during January and February, when the 

 stress may exceed 2.0 dynes cm"^ The meridional 

 components during February through March show no 

 prevailing direction and, in addition, the magnitude tends 

 to be small in comparison to the zonal component. Winter 



Table. 3. — 1956-1970 mean monthly heat used for evaporation computed with neutral stability coefficient, Q(Eli4. 

 corrected for stability, Q(E)s, in units of cal cm ' day '. Range of relative differences for individual months indicated 

 by 4%. 



Table 4.— Mean monthly heat exchange processes at Ocean Weather Station V, 

 1956-70, computed with mean monthly meteorological properties (M) versus those 

 computed with mean daOy properties (D). Units are cal cm'' day'' . 



Radiation from sun and sky. 

 Effective back radiation. 

 Heat used for evaporation. 



Conduction of sensible heat. 



Net heat exchange across the sea surface. 



16 



