Tsunami of April 1, 1946 — Macdonald et at. 
29 
the southern shores. Thus the water reached 
considerably greater heights along the south¬ 
ern coast of the nearly round island of 
Kauai (Fig. 3) than along the southern coast 
of the angular and elongate island of Molo¬ 
kai (Fig. 5), even though the heights along 
the northern coast of Molokai were on the 
average perhaps a little greater than those 
on the northern coast of Kauai. The contrast 
between the very high average height on the 
northern coast of Molokai and the very low 
average height on the southern coast is 
greater than that between the two sides of 
any other island, although the difference 
between the extreme highs and lows is al¬ 
most exactly the same as on the island of 
Hawaii (Fig. 7). 
Exposure to storm ivaves .—At the time of 
the tsunami, large storm waves had been run¬ 
ning for several days. As already pointed 
out, these storm waves riding in on the backs 
of the broad swells of the tsunami in places 
undoubtedly increased the height to which 
the water dashed on shore. Moreover, in 
other places, where the rise in water level 
due to the tsunami was gentle, storm waves 
on top of the tsunami were responsible for 
much of the damage. The generally greater 
violence of the waves on the windward 
(northern and northeastern) coasts as com¬ 
pared to that on the leeward coasts may have 
been in considerable part the result of the 
large storm waves which were driving in on 
the windward coasts. Places on the wind- 
Fig. 4. Map of the island of Oahu, showing the heights reached by the water during the tsunami 
of April 1, 1946. Heights are in feet above lower low water. 
