6 Water Characteristics 



Monthly averages of daily measurements of surface water temperature, 

 visibility, and density at the seaward end of the FRF pier are given in 

 Table 8. The summaries represent single observations made near 0700 EST 

 and, therefore, may not reflect daily average conditions since such characteris- 

 tics can change within a 24-hr period. Large temperature variations were 

 common when there were large differences between the air and water 

 temperatures and variations in wind direction. From past experience, 

 persistent onshore winds move warmer surface water toward the shoreline, 

 although offshore winds cause colder bottom water to circulate shoreward, 

 resulting in lower temperatures. 



Table 8 



Mean Surface Water Characteristics 



Annua I 



14.5 14.8 





Temperature 



Visib 



ility 





deg 



C 



m 









1980- 





1980- 



onth 



1994 



1994 



1994 



1994 



Jan 



5.3 



6.3 



1.4 



1.3 



Feb 



4.4 



5.6 



1.9 



1.8 



Mar 



6.7 



7.1 



1.5 



1.5 



Apr 



11.3 



11.0 



1.8 



1.9 



May 



15.7 



15.3 



1.8 



2.3 



Jun 



21.0 



19.5 



3.3 



3.3 



Jul 



21.6 



21.8 



3.1 



3.7 



Aug 



21.1 



23.4 



2.9 



3.2 



Sep 



22.2 



23.0 



2.3 



2.2 



Oct 



18.1 



19.3 



1.1 



1.5 



Nov 



15.7 



14.9 



0.8 



1.1 



Dec 



11.2 



10.1 



0.6 



1.1 



Density 

 q/cm 









1980- 



1994 



1994 



1.0239 



1.0233 



1.0215 



1.0230 



1.0218 



1.0227 



1.0213 



1.0222 



1.0205 



1.0217 



1.0207 



1.0212 



1.0232 



1.0215 



1.0222 



1.0206 



1.0216 



1.0209 



1.0219 



1.0218 



1.0236 



1.0229 



1.0229 



1.0234 



1.0221 



Temperature 



Daily sea surface water temperatures (Figure 19) were measured with an 

 NOS water sampler and thermometer. Monthly mean water temperatures 

 (Table 8) varied with the air temperatures (see Table 2). 



42 



Chapter 6 Water Characteristics 



