GLOSSARY 



HURRICANE SURGE: the mass of water causing an increase in 



elevation of the water surface above predicted astronomical 

 tide at the time of a hurricane; it includes wind set-up; 

 sometimes the maximum increase in elevation is referred 

 to as the surge. 



HURRICANE TIDE: the rise and fall of the water surface d ^ring 

 a hurricane, exclusive of wave action, 



KNOT: a velocity equal to one nautical mile (6080, 2 ft, ) per hour 

 (about 1, 15 statute miles per hour). 



OVERTOPPING: that portion of the wave runup which goes over 

 the top of a protective structure. 



PONDING: the storage of water behind a dike or wall from local 

 runoff and/or overtopping by waves. 



POOL BUILDUP: the increase in elevation of water surface be- 

 hind a structure due to runoff and/or overtopping by waves, 



RUNUP: the rush of water up the face of a structure on the 



breaking of a wave. The height of runup is measured from 

 the still-water level. 



SIGNIFICANT WAVE: a statistical term denoting waves with the 

 average height and period of the one-third highest waves of 

 a given wave train. 



SPRING TIDE: a tide that occurs at or near the time of new and 

 full moon and which rises highest and falls lowest from the 

 mean level, 



STILL WATER LEVEL: the elevation of the water surface if all 

 wave action were to cease, 



STORM SURGE: same as "hurricane surge, " 



