657 New Islands Discovered Worldwide

Here's something you don't see every day — hundreds of new islands have been discovered around the world.

The Earth has 657 more barrier islands than previously thought, according to a new global survey by researchers from Duke University and Meredith College in Raleigh, N.C.

The researchers identified a total of 2,149 barrier islands worldwide using satellite images, topographical maps and navigational charts. The new total is significantly higher than the 1,492 islands identified in a 2001 survey conducted without the aid of publicly available satellite imagery.

Barrier islands often form as chains of long, low, narrow offshore deposits of sand and sediment, running parallel to a coast but separated from it by bays, estuaries or lagoons. Unlike stationary landforms, barrier islands build up, erode, migrate and rebuild over time in response to waves, tides, currents and other physical processes in the open ocean environment.

All told, the world's barrier islands measure about 13,000 miles (21,000 kilometers) in length. They are found along all continents except Antarctica and in all oceans, and they make up roughly 10 percent of the Earth's continental shorelines. The northern hemisphere is home to 74 percent of these islands. (read more)