EM 1110-2-1100 (Part II)
30 Apr 02
Figure II-3-1.
Waves propagating through shallow water influenced by the underlying bathymetry and
(2) For most of the open U.S. coastline, Wave Information Study data or data from gauges provide
adequate spacing of sites along the coast to give estimates of the wave climate that can be used as input to
nearshore transformation studies. In other places or for simulation of a specific event, a special hindcast of
the deepwater wave climate may be required to provide input for a transformation analysis.
c. Importance of water level. Near the coast, variable water depths can produce major variations in
wave conditions over short distances. The important physical parameter is the depth of the water on which
the surface waves are traveling. In nature, water depth is not a constant: it varies with tide stage, hurricane
or extratropical storm surge, or for a variety of other reasons (Part II-5). These variations in water level
influence wave breaking. Hence, any study of wave transformation must account for expected water levels
for the site and the situation of interest.
II-3-2
Estimation of Nearshore Waves