Americans looking to buy seaside property would do well to study the first ever nationwide map showing how and where natural habitats like reefs and vegetation best protect coastal residents from rising seas and catastrophic storms like last year's Hurricane Sandy. (See "Hurricane Sandy Pictures: Floods, Fire, Snow in the Aftermath.")

Shoreline engineering like seawalls can be effective but also expensive, environmentally undesirable, and a detriment to tourism and seaside recreation. But conserving and restoring nature's own coastal habitats can also help save lives. Now Stanford University's Katie Arkema and colleagues have provided a national map of where natural habitats do most reduce risk to people and property—and where they may need help.

Coastal habitats including marshes, dunes, seagrass beds,