Mid-Atlantic
A ghost forest on the N.C. coast. via NC State News

NC - Study Finds Spreading Ghost Forests on N.C. Coast May Contribute to Climate Change

A new study found the spread of ghost forests across a coastal region of North Carolina may have implications for global warming.

Ghost forests are areas where rising seas have killed off freshwater-dependent trees, leaving dead or dying white snags standing in marsh.

The study found that the transition from forest to marsh along the coastline of the Albemarle-Pamlico Peninsula led to a significant loss in the amount of carbon stored in the plants and trees above ground. When released into the atmosphere as a gas, carbon can contribute to global warming. However, researchers also uncovered some ways landowners can offset some of those carbon losses.

“Many people think about sea-level rise as being more of a long-term threat,” said the study’s lead author Lindsey Smart, a research associate at the North Carolina State University Center for Geospatial Analytics. “But we’re actually seeing significant changes over shorter time periods because of this interaction between gradual sea-level rise and extreme weather events like hurricanes or droughts, which can bring salt water further inland.”

In the study, researchers tracked the spread of ghost forests across 2,485 square miles on the peninsula. They found that on unmanaged, or natural, land such as publicly owned wildlife areas, ghost forests spread across 15 percent of the area between 2001 and 2014.

Using models created using data on vegetation height and type in the area, they calculated that across the 13 years of the study, 130,000 metric tons of carbon were lost from the spread of ghost forests on unmanaged land.

According to the U.S. Environmental Protection Agency’s Greenhouse Gas Equivalencies Calculator, that’s equivalent to what would be emitted into the air by 102,900 passenger vehicles driven for one year.

“Coastal forests are really unique in that they store carbon both in their foliage, and in their really rich organic soil,” Smart said. “As saltwater intrusion increases, you’re going to see impacts both to the aboveground and the belowground carbon. While we measured aboveground carbon losses, the next step will be to look at the response of these carbon stores below ground to saltwater exposure.”

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