88. What is a storm surge? 



A storm surge is caused by a combination of meteorological and 

 astronomical factors. Gravitational effects of the moon and sun pro- 

 duce tides. Storms, and particularly hurricanes, may raise the normal 

 tide level by several feet. High winds blowing from one direction for a 

 prolonged period (usually 10-12 hours or more) can physically "pile up" 

 water on shore (or move it off shore). The effect is particularly notice- 

 able, and most dramatic and hazardous, along shorelines of estuaries and 

 semienclosed seas. This amounts to transport of a substantial volume of 

 water by the frictional meshing of two fluids— air and water. When 

 storms occur during times of highest tides, the results may be disastrous. 



When the water level is raised, higher waves can result from the com- 

 bination of greater depth and strong winds. The storm surge resulting 

 from a hurricane can last through one or two tidal cycles. 



In 1953, a storm surge occurring at a time of particularly high tides 

 flooded the coast of Holland, killing more than 1,800 people. The same 

 storm surge killed more than 300 people in England. Since that time, a 

 flood warning service has been set up in Britain to forecast the probable 

 height of a surge 12 hours before it strikes. 



Deacon, G. E. R. (Ed.) 



Seas, Maps, and Men, Doubleday and Company, 1962. 

 Dunn, G. E., and B. I. Miller 



Atlantic Hurricanes, Louisiana State University Press, New Orleans, 



1960. 

 Gaskell, T. F. 



World Beneath the Oceans, American Museum of Natural History, 



1964. 



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