Sea Level Rise Creating ‘Ghost Forests,’ New Wetlands Along Eastern Seaboard

Sea level rise has long been an enduring risk on America’s shores, particularly along the East Coast. The obvious threats are to the real estate markets along the Atlantic shore, particularly in Florida.

But now there is mounting evidence that sea level rise is creating what researchers often call “ghost forests.” As Wayne Perry of the Associated Press recently highlighted in a recent report, sea level rise is forcing salt water into more water tables, killing coastal trees from Canada down through the mid-Atlantic and Florida before these effects continue to wrap around the Gulf of Mexico coast and then westward to Texas.

The results include increasing nitrogen runoff, in turn contributing to algae blooms that kill fish and other marine life. The continued loss of these coastal forests could also threaten farms as well as the forests that are integral to U.S. paper company supply chains.

The geographical characteristics of the mid-Atlantic and southern U.S., which are noted by their low elevation and gentle slopes, make much of the Eastern Seaboard’s coastal forests susceptible to sea level rise over the next few decades. Academic research has suggested that high tides have increased several inches over the past decade, a rate three times faster than average across the rest of the world.

While Perry and other journalists deserve credit for shining light on how these ghost forests can wreak havoc on ecosystems, this trend has been decades, even centuries, in the making. As anyone stuck in a traffic jam along I-95 can attest, the East Coast’s dense population and continued development has created a perfect storm. One researcher, Matt Kirwan of the Virginia Institute of Marine Science, has long been ahead of the curve in understanding what is behind this growth in ghost forests and what their future impacts could become. The nutrients used in farming, changes in sediment patterns and rates in land subsidence all have contributed to the declining health of coastal forests. Storms and flooding then add even more damage to these fragile environments.

On the plus side, many wetlands across this region have proven to be not only resilient, but have even thrived. And some changes in the East Coast’s climate have been a net positive, depending on one’s perspective. For anglers, the arrival of the Atlantic Croaker, a rare fish along New Jersey’s shores only a decade ago, has been a benefit. The flip side to that argument has been that other local fish have declined in numbers as they seek colder waters farther north.

For Kirwin and other scientists, the Goodwin Islands in Virginia’s Hampton Roads region has been the laboratory for observing the various changes as coastal forests become wetlands. Old maps and soil testing has shown that during the 1850s, these islands in the Chesapeake Bay estuary had twice as much forest than they currently host. Trees have suffered as invasive species have taken root; but researchers who visit to study this undeveloped area says this cluster of islands could hold clues for what is store for the East Coat’s shores later this century.

This work may be too late for some ecosystems, however. The Atlantic white cedar, for example, once covered 115,000 acres across New Jersey. Now there are only about 30,000 acres left home to these trees, which can live up to 300 years. These forests’ loss is just one casualty the Garden State has suffered due to coastal storms and flooding, along with the approximate $1 billion losses due to property and farm damage well before Hurricane Sandy hit in 2012.

Image credit: Leon Kaye