Diagrams , similar to figure 5 3 have been drawn for the same wave period 

 but different directions with a slightly different refraction effect. Figure 

 6 shows in detail the refractive effect near shore of waves which, in the 

 open ocean, approached from the west, southwest, and west southwest,, In 

 figure 6, which was prepared by transferring wave fronts from smaller scaled 

 diagrams as illustrated by figure 5, waves from these three directions have 

 practically the same wave front orientation in the vicinity of Santa Barbara c 

 Figure 7 shows waves approaching the channel islands from the south and south- 

 east. 'Vave fronts from figure 7 have been transferred to a larger scale 

 chart and then carried into shore as shown in figure 3„ Fxamination of fig- 

 ure 7 shows that waves from the southeast and those from the south, which are 

 refracted around the east end of Anacapa' Island, both approach the shoreline 

 in the vicinity of Santa Barhara with practically the same alignment; hence, 

 the wave fronts in figure 8 are indicated as being for both of these initial 

 wave directions „ Waves passing between Santa Cruz and Anacapa Islands show 

 so great an increase in crest length that their effect near shore could not 

 be noticed in comparison with 7/aves passing to the east of Anacapa Island „ 



The wave and swell diagrams of the Hydrographic Office (2) had not been 

 prepared at the time this study was made and conclusions regarding the sources 

 of waves were based upon wind data, from which it apoeared certain that waves 

 from the south or southeast would be infrequent and that waves approaching in 

 the sector between west and north would occur during most of the year« The 

 limited fetch between Santa Barbara and the Channel Islands and the moder- 

 ate winds precluded the possibility of local wind waves playing an appreci- 

 able part in the shoreline changes „ 



The refraction diagrams and supporting wind data seemed to justify the 

 following conclusions? 



lo Waves from westerly directions will break obliquely and 

 generate a littoral current during most of the year a 



2„ The intensity of wave action at Santa Barbara will be 



materially less than at points on adjacent exposed coasts 

 for any wave direction in deep water, including southeast — 

 the direction of greatest exposure,, 



3» Conclusions regarding the effect of long waves arrived at by 

 observations on exposed coasts are not directly applicable at 

 Santa Barbara „ 



It might be said that these conclusions could be reached merely by 

 inspection without drawing refraction diagrams and this comment would be 

 valid in a formal sense „ However, one is merely substituting a mental 

 construction of the diagrams for the graphical development and this is 

 readily done after some experience „ Usually, only a few periods and direc- 

 tions need be drawn even for quantitative use, the remaining conditions being 

 supplied by inspection and interpolation 



11 



