THIS MONTH AT THE DELAWARE COAST
Question of the Month - February, 2003
Why do I sometimes see piles of foam on the beach at the water's edge?
While it is common to see bright white foam in the surf
as waves break, there is sometimes an especially large accumulation of
foam on the beach during storms. This foam line is simply the remnants
of waves after they have broken.
Sea foam is basically made of air bubbles separated
by a film of liquid. Foam is produced when any gas, like air, is mixed
into a liquid. Most of the foam that is washed up along Delaware beaches
is produced by breaking waves. As a wave breaks, the crest (or top part)
of the wave forces air into the sea. The air is not stable in ocean water,
and it rushes out in the form of many tiny air bubbles.
During coastal storms, as strong wind blows over the ocean, the waves get larger and contain more power. Storm waves breaking along Delaware's shoreline usually have enough energy to force enough air into the water to produce the longer lasting piles of foam.
Even though the foam may look dirty and it may have an
oily looking sheen, sea foam is usually harmless. There are chemical compounds
in sea water, known as organic compounds, that cause the foam to be rather
long lasting and durable. Additionally, even some of the salts in seawater
may help to trap the air into bubbles, and eventually foam. Fine particles
of sediment may attach themselves to the foam bubbles, giving it a dirty
appearance.
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.
