Carolina Environmental Diversity Explorations

Hurricanes on sandy shorelines · By Dirk Frankenberg

Masonboro Island after Hurricane Floyd

Masonboro Island after Hurricane (Beach & Berm)

Figure 4. Masonboro Island flattened by Hurricane Floyd. (Photograph by the author. More about the photograph)

Figure 4 shows what a low sand volume barrier island looks like after a hurricane. If you are thinking that it looks flat, you are absolutely correct! It is flat. That is what happens when a 7- to 12-foot storm surge with 8- to 10-foot waves on top of it floods across a barrier island. Any sediment that sticks up is washed away, and the island surface becomes a broad, flat terrace.

Figure 4 shows the island with the offshore ocean in the upper right, and the landward salt marsh in the upper left. In between is the flat terrace that was made of the island’s sand by the waves and storm surge of hurricanes Dennis and Floyd.

Definitions

barrier island n.
A long, relatively narrow island running parallel to the mainland, built up by the action of waves and currents and serving to protect the coast from erosion by surf and tidal surges.
hurricane n.
A severe tropical cyclone originating in the equatorial regions of the Atlantic Ocean or Caribbean Sea or eastern regions of the Pacific Ocean, traveling north, northwest, or northeast from its point of origin, and usually involving heavy rains and has surface wind speeds greater than 74 miles (or 119 kilometers) per hour. [more]
storm surge n.
Water that is pushed toward the shore by the force of the winds swirling around a storm. [more]
salt marsh n.
A low coastal grassland frequently overflowed by the tide.