October 29, 2007—The United States' Atlantic and Gulf of Mexico beaches draw millions of tourists a year and provide summer homes for many city dwellers.

But sands shift, and low-lying islands are at risk from the combined impact of sea level rise and hurricanes.

At the 2007 meeting of the Geological Society of America yesterday in Denver, Colorado, geologists listed some of the region's most endangered communities, as seen above.

The list isn't intended to be comprehensive. At the meeting, Robert Young of Western Carolina University warned against feeling a false sense of security simply because a particular community isn't mentioned.

"With the right (or maybe wrong) storm, coming from the right direction, every piece of property in the immediate coastal zone is vulnerable," he said in his prepared remarks.

—Richard A. Lovett

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