Tropical cyclones - Extreme Events: A Physical Reconstruction and Risk Assessment - page 97

Foredune

1

Marine inundation

Storm tide level

Wave run-up

2

Marine inundation

Storm tide level

Extent of dune retreat

Dune overtopping by wave run-up

Building

3

Marine inundation level
(including waves)

Filled
Land

Storm tide level

Extent of vertical erosion
and new dune profile

Original dune profile

4

Structural damage
to building

Height of dune resulting from stage 3 erosion
Marine inundation level
(including waves)

Undermining
of fill

Storm tide level

Storm tide level

New dune profile following vertical dune erosion
after dune overtopping by wave run-up shown in
stage 3

Figure 4.9. Schematic model of the relationship between dune erosion and the
height of marine inundation. When inundation reaches the crest of a dune it will
erode vertically. Where inundation is below the crest of a dune, it will erode
horizontally.