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Dangerous currents in the surf

AUG 01, 1949
Rip currents, not undertow, can sweep the unwary swimmer seaward. Knowing how to spot these rips, and what to do if caught in a strong one, may help a swimmer save his life.
Francis P. Shepard

Surf bathing leads to the drowning of thousands of people each summer. “Caught in the undertow” is the usual explanation for these disasters and yet there may be no such thing as undertow. In dictionaries it is defined as “the current beneath the surface which sets seaward when waves are breaking on the shore.” Many geological textbooks contain brief discussions of undertow, ascribing it to the seaward return of landward driven surface water.

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More about the authors

Francis P. Shepard, Scripps Institution of Oecanography, University of California, La Jolla, California.

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This Content Appeared In
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Volume 2, Number 8

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