ECOLOGY OF BUZZARDS BAY An Estuanne Profile 



117 



erosion of the marsh surface in many areas has cre- 

 ated shallow depressions that retain standing water 

 and are likely to restrict regrowth for many more 

 years. 



6.2.2. Storms 



In contrast to the gradual effects of continuous 

 relative sea-level rise, storms are infrequent and 

 sometimes cause major physical and biological 

 changes in a matter of moments. The reason for the 

 temporal disparity is that sea-level rise in Buzzards 

 Bay is caused by geologic processes of land sub- 

 sidence and changes in global sea level, while the 

 effects of storms are the result of rapidly changing 

 atmospheric and tidal phenomena that exist for hours 

 to days. The gradual and infrequent processes that 

 drive coastal changes both produce management 



problems because the effects are not readily ob- 

 servable on an annual scale. 



Although storm occurrence is irregular and un- 

 predictable from year to year, over longer periods 

 there is a probability of a major storm every 1 -2 

 years and smaller storms at a much higher frequency 

 (Fig. 6.12; Aubrey and Speer 1984). Storm oc- 

 currence is seasonal, composed of the Atlantic tropi- 

 cal storms in late summer and fall and northeast 

 storms of winter. In all, there have been at least 1 60 

 gales (wind greater than 1 5 m/s) in the Atlantic 

 coastal region of Cape Cod from 1870 to 1975 

 (cf. Aubrey and Speer 1 984). It is difficult to deter- 

 mine the precise number of storms per year over 

 past centuries because the early records tend to 

 include only major storms. The apparent recent in- 

 crease in storm frequency since 1 948 demonstrates 



1970 1980 



CO 



E 

 o 

 to 



CD 



E 



c 



3 - 



« 2 



c 



1800 



1820 



1840 



1860 



1880 



1900 



1920 



1940 



1960 



1980 



Year 



Fig. 6.12. Cyclone activity affecting the area of Cape Cod (60° W to 70° W, 37.5° N to 42.5° N) from 1885 to 

 1982. Storm count is indicative of storm number and duration, not individual events The data addresses long 

 term trends in relative storm occurrence From Aubrey and Speer (1984) 



