Twenty Years And 35 Tropical Cyclones Reshape NC's Coast

May 29, 2018

Hurricane Matthew, 2016
Credit NASA / Flickr

North Carolina's coastal ecosystem has drastically changed because of two decades of hurricanes and other tropical cyclones.

That's according to researchers at UNC-Chapel Hill and N.C. State University who studied water samples in the estuary where the Neuse River meets the Pamlico Sound. 

The results suggest more frequent storms have caused more organic matter and nutrients like phosphorous and nitrogen to flow into the river. Hans Paerl of UNC's Institute of Marine Sciences said  those nutrients are linked to water quality.

"The more nutrients and the more organic matter we get coming in, the more we have problems with algal blooms, for example, that feed off of those nutrients and also low oxygen conditions that end up in our estuaries and coastal zones," Paerl said.

The study also describes a cycle of nutrient flow that starts when a major storm hits.

"The storms come, bring in the organic matter, that's converted to CO2 - or carbon dioxide - that can then be vented back up into the atmosphere, and we know that carbon dioxide enrichment in the atmosphere can lead to warming. The warming can then lead to more storms, and so on," Paerl expalined.

Paerl says those conditions can lead to more of what researchers call dead zones, where organisms can't survive on low oxygen. He says the study suggests state and local governments should reevaluate whether they are effectively protecting waterways with buffers.

"It simply means that we have to adapt our land management for this more stormy and more episodic period of climate change that we're experiencing," he said.

Paerl says the changes could also have an economic impact on the coast, which relies heavily on tourism.