Talk about job envy. Stephen Leatherman, the director of the Laboratory for Coastal Research at Florida International University's Hurricane Research Center, spends his days exploring the country's coastlines to compile his own annual list of the top 10 beaches ( Here, T+L gets inside the mind of a man who calls himself Dr. Beach:

Q. Just how beach-obsessed are you?

A. Let's just say my daughter is named Sandy. I couldn't resist.

Q. What makes a beach a clear winner in your eyes?

A. It has to be wide, and it should be sandy; cobble beaches in Maine are interesting, but you can't really lie down. And I like clear, emerald-green water. I actually have 50 criteria in three categories: physical, like riptides; biological, like pollution; and human, like litter.

Q. So what's a favorite beach?

A. Kapalua Bay, on Maui, is phenomenal. I just don't get there often enough because of the long trip.

Q. Black sand vs. white sand?

A. Black sand is exotic, but the water at black-sand beaches is so dark and forbidding. I prefer white sand.

Q. What's a great beach hotel?

A. Hotel del Coronado (1500 Orange Ave.; 800/468-3533;; doubles from $440), in San Diego. It was built more than 100 years ago. And the beach is one I love—very flat, with mica in it, so it shines.

Q. Do you always wear sunscreen?

A. At least SPF 35, and I reapply often. When I meet people they say, "You're Dr. Beach? You look like you live in a closet!" But I don't want my skin to look like my last name.