THIS MONTH AT THE DELAWARE COAST

Click here to view video of the Delaware beach.
Please send in your suggestion for the “question of the month.” Questions and answers will be posted as the months unfold. For more information, contact Wendy Carey.

Question of the Month - March, 2003

Why is there sometimes a cliff on the beach and
other times there is not?

The feature that you describe is often observed on the beach after storms. The beach cliff is also called a scarp. Scarps are vertical cliffs, usually a couple of inches to a couple of feet high, near the water's edge formed by wave erosion during storms or heavy surf. Storms can cause extensive beach and dune erosion, which results in scarping of the dunes and narrowing of the beach.

The scarp is a the residual effect of storm wave attack on beaches. During a storm with high energy waves and higher than normal tide levels, sand is eroded from the beach and deposited in an offshore bar. The return of normal low energy wave conditions eventually moves this sand back onto the beach. Although the beach usually regains its pre-storm shape, some of the sand eroded by storm waves may be lost from the beach system to overwash deposits, the offshore zone, inlets, or spits.

The figure shown here (left) illustrates the impact of wave attack on beaches.

The photographs below show scarps along Delaware beaches after the February 16, 2003 northeast storm.


Please send in your suggestion for the “question of the month.” Questions and answers will be posted as the months unfold. For more information, contact Wendy Carey.