index values. Since negative pressure 

 differences at location 8 represent south- 

 erly winds, the correlation is consistent 

 with the concept of wind-induced advection. 

 Lacking data to make direct estimates of 

 advection, it is not possible to assess the 

 relative importance of this mechanism. The 

 indices may also reflect atmosphere-ocean 

 heat-exchange processes which significantly 

 affect sea surface temperature fluctuations. 



Mean January sea water temperatures 

 from three additional British Columbia 

 stations, Langara Is., Kains Is. and Amphi- 

 trite Point, were found to have year-to-year 

 fluctuations which agreed well with Triple 

 Island data. Correlating January pressure 

 differences at location 8 with January tem- 

 peratures at these stations for the period 

 1941-57 yielded coefficients of -0.67 (Lan- 

 gara Is.), -0,58 (Kains Is.) and -0.58 (Am- 

 phitrite Point). These values, all statis- 

 tically significant at the 2 percent level, 

 are somewhat lower than the correlation of 

 wind with Triple Island sea temperature. 

 However the fact that the correlation is of 

 the same sign and of substantial value for 

 all four stations reinforces the inference 

 that all are affected by some widespread 

 influence such as the wind field or by 

 associated weather conditions. 



Further comparisons of monthly mean 

 sea temperature at Triple Island with pres- 

 sure differences for the same month at 

 location 8 yield correlation coefficients 

 of -0.49 for December, -0.03 for Februjiry, 

 -0.16 for March and 0.04 for April. When 

 the pressure differences at location 8, 

 averaged for December and January (of the 

 same winter) are correlated with Triple 

 Island sea temperatures for the following 

 February, a coefficient of -0.86 is ob- 

 tained. 



Inspection of the Triple Island sea 

 temperature data reveals that year-to-year 

 fluctuations of December and January means 

 are followed very closely by the fluctua- 

 tions of February means and, to a consider- 

 able degree, by fluctuations of March, April 

 and May means. Thus, the strong correlation 

 of December-January average wind indices 

 with February temperatures may be readily 

 explained by persistence of December cuid 

 January temperature anomalies into February, 

 coupled with the relatively good correla- 

 tions between wind indices and temperatures 

 for December and January. If the latter 



are significant evidence of real physical 

 mechanisms linking wind intensity to sea 

 temperature, it is pertinent to inquire why 

 such mechanisms fail to be manifest in the 

 correlations involving February, March and 

 April wind indices and sea temperatures. 



A tentative answer to this question is 

 suggested by the differences in mean ajnpli- 

 tude of both wind index and sea temperature 

 fluctuations for the individual months. 

 The monthly standard deviations computed 

 from the Triple Island temperature data are 

 1.61 (Dec), 2.24 (Jan.), 1.82 (Feb.), 1.28 

 (Mar.) and 1.14 (Apr.). From similar com- 

 putations on the location 8 pressure differ- 

 ences one obtains standard deviations of 

 3.02 (Dec), 4.12 (Jan.), 2.92 (Feb.), 2.03 

 (Mar.) and 1.71 (Apr. ). 



It is evident in both sets of values 

 that fluctuations are generally largest in 

 January. Thus it is conceivable that tem- 

 perature anomalies produced in December axe 

 not sufficiently large to obscure the corre- 

 lation between monthly mean temperatures 

 and wind indices in January. Anomalies 

 produced in December and January, however, 

 do tend to overshadow the effects of wind 

 on monthly mean temperature in subsequent 

 months. 



It must be mentioned that nonadvective 

 heat-exchange processes may influence sea 

 surface temperature fluctuations to a sub- 

 stantial degree. Tabata (1956) has shown 

 that in the vicinity of Triple Island the 

 ocean experiences net cooling in winter 

 when heat losses, due principally to evap- 

 oration, conduction and back radiation, 

 exceed heat gains by solar radiation. The 

 maximum rate of net heat loss occurs in 

 January. By April the balance shifts such 

 that the ocean receives a small net gain of 

 heat. A cursory comparison of the wind 

 indices with Tabata's computations of net 

 heat loss for individual months suggests 

 that these two quantities are not mutually 

 independent. For example, Tabata cites 

 January 1950 as a month characterized by 

 strong northerly winds, low moisture content 

 and cloudless skies and notes that these 

 conditions are ideal for cooling at the sea 

 surface through the three principal pro- 

 cesses of heat loss — conduction, evaporation 

 and back radiation. 



Since, in this example, these processes 

 would affect sea surface temperatures in 



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