FETCH LENGTH - In wave forecasting, the horizontal distance (in the 

 direction of the wind) over which the wind blows, 



FIRTH - A narrow arm of the sea; also the opening of a river into the 

 seao 



FJORD (fiord) - A long narrow arm of the sea between highlands, 



FLOOD CURRENT - The movement of the tidal cur-rent toward the shore or 

 up a tidal stream, 



FLOOD TIDE - A non-technical term referring to that period of tide be- 

 tween low water and the succeeding high water; a rising tide, 

 (See Figure A-IO) 



FOAM LINE - The front of a wave as it advances shoreward, after it 

 has brokeno (See Figure A-U) 



FOLLOWING WIND - In wave forecasting, wind blowing in the same direction 

 that waves are travellings 



FORESHORE - The part of the shore, lying between the crest of the sea- 

 ward berm (or the upper limit of wave wash at high tide) and the 

 ordinary low water mark, that is ordinariljr traversed by the 

 upriish and backrush of the waves as the tides rise and fall, 

 (See Figure l) 



FREEBOARD - The additional height of a structure above design high 

 water level to prevent overflow. Also, at a given time the 

 vertical distance between the water level and the top of the 

 structure On a ship, the distance from the water line to main 

 deck or gunwale, 



FRESHET - A rapidly rising flood in a stream resulting from snow melt 

 or rainfall, 



FRINGING REEF - A reef attached to an insular or continental shore, 



GENERATING AREA - In wave forecasting, the continuous area of water 

 surface over which the wind blows in essentially a constant di- 

 rection. Sometime used synonymously id.th FETCH LENGTH. Also 

 FETCH. 



GENERATION OF WAVES - (l) the creation of waves by natural or mech- 

 anical means; (2) In wave forecasting, the creation and growth 

 of waves caused by a wind blowing over a water surface for a 

 certain period of time. The area involved is called the GENER- 

 ATING AREA or FETCH. 



A-13 



