85. At the seaward end of the pier, the 1981 annual average current 

 speed was 12 cm/sec southward, which agrees with the longer term average. 

 Monthly means (Table 7 and Figure 26) show that strong southerly flows oc- 

 curred during October and November 1981, which reflects the above-average 

 incidence of northeasters during the period. This contrasts markedly with 

 the 4-year average indicating maximum speeds in February and March. With 

 the exception of April, all pier end mean monthly flows were to the south. 



86. Both surf zone stations showed a general pattern of strong south- 

 ward flow during the winter (Figure 26) and northerly flows during the summer 

 when waves frequently approached from the south. February, however, was ex- 

 ceptional in the sense that currents were northward at both stations, with 



a southward minimum at the pier end. 



87. The Mariner's Weather Log (NOAA/National Oceanographic Data Center 

 1981) states "the monthly mean sea-level pressure pattern was vastly different 

 from climatology." High-pressure systems were unusually prevalent for Feb- 

 ruary, off the east coast of the United States, accounting for the greater 

 frequency of southerly winds . 



88. Because of seasonally reversing longshore current patterns at surf 

 zone locations, the annual resultant longshore current speeds were less in 

 the surf than at the pier end; i.e., 6 cm/sec at the pier midsurf zone and 

 only 3 cm/sec along the updrift beach. Other differences include an indi- 

 cation that individual current speeds were generally greater at the pier 

 mid-surf zone than at the other two locations and that, occasionally, mean 

 monthly currents in the surf zone were oppositely directed at the pier and 

 the updrift beach. 



89. On four occasions during 1981 (see tabulation below), the surface 

 current speed exceeded 150 cm/sec. In each case, the currents were south- 

 westerly directed and coincident with strong winds and high seas nearshore. 





Current 



Location 





Wind 



Wa' 



ve* 



Bre; 

 ref 



iker Angle 



Date 



Speed 

 cm/sec 



171 



Direction 

 Southward 



Speed 

 m/s 



8 



D: 

 ref 



irection 

 True North 



50** 



Height 

 m 



Period 

 sec 



4.6 



True North 

 deg 



18 Mar 



Beach 



1.1 





60 



17 Aug 



208 



Southward 



Beach 



10 





20 



1.3 



5.3 





55 



24 Oct 



203 



Southward 



Pier raidsurf 



13 





20 



1.4 



7.1 





60 



12 Nov 



203 



Southward 



Pier midsurf 



18 





20 



1.7 



7.5 





50 



* Wave measurements taken from gage 615 at 100 in offshore. 

 ** Note pier oriented at 70 deg ref True North. 



53 



