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BIOLOGICAL REPORT 31 



the high frequency of major storms in the region. 

 The magnitude of the effect of storms on the Buz- 

 zards Bay system is determined by a variety of fac- 

 tors, most importantly wind speed and direction, 

 tide stage, rainfall, and season. 



Storms, both hurricanes and "nor'easters," tend 

 to approach Buzzards Bay from the south. Wind 

 speed and direction are determined, in part, by the 

 track of the storm center as it passes the bay mov- 

 ing northward. Storms in the northern hemisphere 

 rotate in the counter-clockwise direction (Pig. 6. 1 3). 



The effect of this rotation in a storm moving north- 

 ward is that the wind speed of its eastern portion is 

 effectively increased by the storm's advance while 

 the winds of the storm's western portion have a 

 lower ground speed. The enhanced wind effect on 

 the eastern side of the storm has termed that side of 

 the cyclone the "dangerous semi-circle" (Oldale 

 1 992). The effect on Buzzards Bay is that storms 

 with centers passing to the west tend to produce 

 the most coastal erosion and flooding. 



'V 



Fig. 6.13. NOAA satellite photograph of Hurricane Bob, 19 August 1991, at 1131 h. The eye of the hurricane is 

 south of Buzzards Bay, off the coast of New Jersey The counter-clockwise rotation of the storm can be clearly 

 seen as the storm moves northward From Potter (1991). 



