The Overlooked Ground Zero for Sea Level Rise

If I asked you to name the three areas of the US most vulnerable to sea level rise, what would you say?

The first two are fairly obvious.  The Mississippi Delta?  Correct.  Southern Florida?  Also spot on.  But the third?  You might guess the Chesapeake Bay or the Gulf Coast of Texas (close, it comes in at 4th).  The answer is actually a region that receives relatively paltry national attention in the discussion of sea level rise: the Albemarle-Pamlico region of North Carolina.

I was fortunate enough to spend some time last weekend in beautiful (and distant) Duck, NC for a meeting of the Foundation’s Advisory Panel.  We heard from a number of experts–from the North Carolina Coastal Federation, Environmental Defense Fund, Audobon North Carolina, and local municipalities–on the challenges facing this changing landscape.

Many folks have heard of the NC Outer Banks–that thin strip of island land  between mainland North Carolina and the Atlantic Ocean.  Hatteras Island, the 42 mile long, northernmost island in the outer banks chain, stands between the open ocean and the Albemarle and Pamlico sounds.  Beyond those sounds, moving inland, are estuaries that form a backbone of vital ecosystems.  The Outer Banks are a highly developed tourist destination, with beachfront rental homes and condos rising out of the fragile dunes.  Inland, the Northeastern counties closest to these sounds and estuaries are some of the poorest in the state.

And it’s all extremely vulnerable to sea level rise.

In my next post, I’ll discuss what a few organizations, municipalities, and homeowners are doing (or could be doing) to prepare for and adapt to sea level rise.  But first I want to make two quick points about sea level rise:

(1) We can, in good faith, acknowledge that this is an issue worthy of our attention without delving into climate change per se.  I believe the preponderance of scientific evidence that points to human-exacerbated climate change.  But even if you dispute the causes, you can’t deny the fact that the sea is slowly rising (see chart below).  This means that regardless of whether or not you believe that we should be acting to curb emissions or limit mankind’s impact on the planet, we’re still facing an inevitable economic and quality of life crisis based on the productive lands that are threatened by rising seas.  Such a crisis demands preparation, since the impacts we’re talking about will be felt long before this land is literally and visibly underwater.

Chart courtesy GlobalWarmingArt.com

(2) We hear about sea level rise and the image we think about is that of a gradually rising tide–what some folks I’ve heard call the “bathtub effect.”  The sea gently rises at a rate so slight as to be imperceptible on a day-to-day basis.  But to think of sea level rise in these terms misses the point.  The problem is not the gradual rise: natural (plant, animal, etc.) and human (infrastructure, building patterns, etc) systems can adjust to gradual change.  What neither can adequately adjust to is the sudden surge that accompanies an already-higher sea level during a coastal storm.  Salt water from these storms encroaches on water and land that supports salt-intolerant species.  The impact of storms on man made development and infrastructure likewise worsens as sea levels increase.  Fragile systems–like the developed islands of the outer banks–are tipped out of balance by major storm events like Katrina.  We’re used to labeling these storm events (like hurricanes Katrina, Fran, Floyd, Ike) unpreventable acts of God; but the fact of the matter is that sea level rise, and our reluctance to prepare for its effects, exacerbates natural phenomena with catastrophic results.

The vulnerability of this region is important for a number of reasons, including:

1. Economics.  The natural beauty of the outer banks and Albemarle sound has created a large tourism economy for an otherwise very poor region of NC.  Losing rental properties, as well as the protected beaches, parks, and lands that attract tourists, would have a tremendously negative impact on the region.  Furthermore, encroachment of salt water on coastal farm lands will be detrimental to many famers in the area.
2. Vulnerable Populations at Sea Level.  I’ve touched on the poverty of this region (and I’ll delve into it further in my next post).  But adding to the stresses on an at risk population is the fact that this area is exceedingly low relative to sea level.  On the Southern edge of the North Carolina coast (near Wilmington), every mile inland is about 3 feet higher in elevation; in the Albemarle-Pamlico region, every mile inland is only about 3 inches higher in elevation.  This translates into a number of people without the means to relocate or adapt to sea level rise on the front lines of these changes.
3. Fish.  70% of commercially harvested fish spend significant parts of their lives in coastal estuaries like those of the Albemarle-Pamlico region.  The North Carolina Coastal Federation produces a popular bumper sticker that reads “No Wetlands, No Seafood.”  It’s that simple, and it’s the estuarial ecosystems that are most at risk from rising seas.
4. Ecosystem services.  We rely on properly functioning ecosystems to provide essential “services” like clean water, clean air, and dilution of animal and human waste.  With the rapid changes that sea level rise wreaks on coastal ecosytems, those systems do not have time to properly adapt into newly productive (though different) systems.  Whereas an area might naturally evolve from coastal pocosin to saltwater marsh to underwater oyster reef, with rapid sea level rise that same area could turn from coastal pocosin to an ocean desert inhabited by the type of muck that one scientist described as “like black mayonaise.”

Here’s a humbling animation from the Nature Conservancy showing the impact of various sea level estimates (ranging from current rates to worst case scenarios) on the Albemarle-Pamlico region.

Thanks very much to friends from the NC Coastal Federation, Environmental Defense Fund, Audobon NC, and the Nature Conservancy for their patience and for the lessons I’ve tried to pass along here.