Northeast coast may adapt to rising seas.

• Position: Your Life

Much of the coast from Maine to Virginia is more likely to change than simply drown in response to rising seas during the next 70 years or so, according to a study led by the U.S. Geological Survey, Reston, Va. The study is based on a new computer model that captures the potential of the Northeast coast to change--driven by geological and biological forces--in ways that will reshape coastal landscapes.

Researchers report that 70% of the Northeast Atlantic Coast is made up of ecosystems that have the capacity to change over the next several decades in response to rising seas. For example, barrier islands may migrate inland, build dunes, change shape, or be split by new inlets as tides, winds, waves, and currents sculpt their sands. Marshes trap sediment and break down decaying plants into new soil, which may elevate them sufficiently in some areas to keep pace with sea-level increases.

While most sea level-rise models that cover large areas show low-lying coastal land converting to open water in coming decades, many of these inundation models overpredict the land likely to submerge. The USGS model, developed in collaboration with Columbia University's Earth Institute, New York, produces a more nuanced picture of sea level rise as a mosaic of dry land, wetlands, and open seas, rather than as a uniform response across the landscape.

The USGS model is the first to factor in natural forces and make detailed predictions from the 2020s through the 2080s over a large coastal area, some 9,400,000 acres. It is an advance over most regional...