In the face of climate change impact and inevitable sea level rise, Cornell and Scenic Hudson scientists studying New York's Hudson River estuary have forecast new intertidal wetlands, comprising perhaps 33 percent more wetland area by the year 2100. "In other parts of the world, sea level rise has led to net losses of tidal wetland and to permanent inundation," said Magdeline Laba, Cornell senior research associate in soil and crop sciences.

In terms of population, the Hudson River valley is one of the fastest growing regions in the state, she explained, as the transportation network and industry border both sides of the river. "Taking this into account, it is quite surprising that wetlands have any area at all to expand into," Laba said. "There will be a net increase in total wetlands, instead of a decrease, which is really amazing."

The net predicted wetland increase is due to the upland migration of existing marshes, she said. "That's fantastic. I never thought that would be a result. These marshes are amazingly resilient."

The Hudson River estuary hosts one of the largest concentrations of freshwater tidal wetlands in the Northeast, stretching 150 miles from Manhattan to Troy, just north of Albany. While the river might be considered brackish toward Manhattan, about 80 percent of the river's tidal wetlands sit beyond the Atlantic's salty reach.

Sea level rise prompts scientific concern for infrastructure and population near the Hudson, but scientists must preserve its unique biodiversity, Laba said. The river's marshes cycle nutrients, filter water, offer habitat for fish and wildlife, and buffer against storms. Laba conducts research with remote sensing, taking into account various facets of the tidal river's ecology, including shore elevation and slope, land cover, tides and accretion rates, which are how the marshes build up over time.