SURFACE CUHMENTS AT HALF CBS 



(HIQH WATER . 3 HOURSB 



^- Bar i«pr(««ili ■•tocltr of 9 Inoli 



*— Hook foAfflOonn rdocl'y «l 20 t 



»I094-?0)>23 I 



Figure 4.— Surface tidal currents in the Quoddy Region shovring half-ebb and half- 

 flood conditions. 



Quoddy Region and about 25 percent were 

 recovered. During the first 10 days, 9 

 percent were recovered, and during the 

 first 30 days, 17 percent. Inside Pas sama- 

 quoddy Bay, in Cobscook Bay, and in the 

 Passages, the usual distance between 

 release and recovery was of the same 

 order of magnitude as the tidal excursions. 

 Hence, it is difficult to infer net circula- 

 tion in this area. Inside Passamaquoddy 

 Bay, surface circulation on the average 

 appeared to be counterclockwise; how- 

 ever, wind evidently modified this situa- 

 tion markedly. On the whole, wind action 

 is very effective in moving the surface 

 layer. In general, winds with a southerly 

 component tend to confine surface waters 

 to Passamaquoddy Bay, while winds from 

 the north and west remove surface waters 



from the Bay. In each instance, there 

 must be compensating flow at subsurface 

 levels. No clear picture of net surface 

 flow through Letite and Western Passages 

 was established. There is some evidence 

 that, on the average, net flow is outward 

 through Western Passage and inward 

 through Letite Passage. However, there 

 are instances when net flow appears to be 

 reversed. There also are times when 

 surface flow is in the same direction in 

 both passages with a compensating sub- 

 surface flow. Drift-bottle returns plotted 

 on a monthly basis indicate marked 

 changes in pattern of flow both seasonally 

 and for the same month for the 2 years. 

 A small percentage of the drift bottles 

 leave the region; some move along the 

 coast of Maine as far as Massachusetts, 



