56
much was transported westwards into Pamlico Sound. Oceanic waters entered
Pamlico Sound through these gaps. Indeed, one gap, where Ocracoke Island is currently located, was so large that it transformed the shallow body of water, Pamlico
Sound, normally protected from the high energy Atlantic Ocean by the nearly continuous Outer Banks, into an unprotected Pamlico Bay, that was directly connected
to the open ocean. Not only were sediments redistributed, modeling by my colleagues shows that currents adjacent to the breaks in the islands became stronger,
the tidal range within the Bay doubled in places, and the salinity of the Bay also
increased. All of these changes affected the organisms within the Bay. Native
Americans who utilized the resources of this complex coastal system would have
adapted to the new circumstances as did the fish, clams, snails, crustaceans, worms
and smaller organisms, most probably by migrating, if they could do so. The range
of salt-water fish expanded further westward. As salty waters extended further
upstream, species of brackish water fish migrated up the Neuse and Tar-Pamlico
estuaries. Native Americans surely followed them with their nets.
What event caused these drastic changes? Was it a sudden process or was it
gradual? Had it happened before and could it happen again? How do we know that
this environmental perturbation occurred? What are the various lines of evidence
that allow us to understand this, from a geological perspective, very rapid episode
of change? Why should we be interested in this event? What is its relevance to us
today? I’ll try to explain.
Three Hurricanes
I arrived at East Carolina University (ECU) in August 1999. I was the new Chair of
the Department of Geology (now named the Department of Geological Sciences).
In an interesting parallel, I had migrated from the Natural History Museum in
London to ECU because of a change in circumstances, akin to the migration of the
fish and clams noted above (although, of course, I did not think of it in those terms
at that time). I spent a year or so getting used to my new administrative tasks and
then I turned my attention to another item in my job description, research. But three
events occurred within several weeks at the beginning of my first year at ECU. The
low-lying land of eastern North Carolina was hit in quick succession by three hurricanes, Dennis, Floyd and Irene. The result was terrible floods that affected the
region for several years (Figs. 4.1 and 4.2).
We’ve had enough hurricane hits along the Gulf and Atlantic coasts of the US
over the past decade or so to know that some hurricanes are mainly rain events (such
as Floyd), some are wind events, and some are storm surge events. Some terrible
storms combine all three characteristics to horrifying effect. The Floyd floods
affected me personally – my wife, my two children and cat, newly arrived from the
UK, had to inhabit a hotel room for five months, living out of our suitcases until we
S. J. Culver
much was transported westwards into Pamlico Sound. Oceanic waters entered
Pamlico Sound through these gaps. Indeed, one gap, where Ocracoke Island is currently located, was so large that it transformed the shallow body of water, Pamlico
Sound, normally protected from the high energy Atlantic Ocean by the nearly continuous Outer Banks, into an unprotected Pamlico Bay, that was directly connected
to the open ocean. Not only were sediments redistributed, modeling by my colleagues shows that currents adjacent to the breaks in the islands became stronger,
the tidal range within the Bay doubled in places, and the salinity of the Bay also
increased. All of these changes affected the organisms within the Bay. Native
Americans who utilized the resources of this complex coastal system would have
adapted to the new circumstances as did the fish, clams, snails, crustaceans, worms
and smaller organisms, most probably by migrating, if they could do so. The range
of salt-water fish expanded further westward. As salty waters extended further
upstream, species of brackish water fish migrated up the Neuse and Tar-Pamlico
estuaries. Native Americans surely followed them with their nets.
What event caused these drastic changes? Was it a sudden process or was it
gradual? Had it happened before and could it happen again? How do we know that
this environmental perturbation occurred? What are the various lines of evidence
that allow us to understand this, from a geological perspective, very rapid episode
of change? Why should we be interested in this event? What is its relevance to us
today? I’ll try to explain.
Three Hurricanes
I arrived at East Carolina University (ECU) in August 1999. I was the new Chair of
the Department of Geology (now named the Department of Geological Sciences).
In an interesting parallel, I had migrated from the Natural History Museum in
London to ECU because of a change in circumstances, akin to the migration of the
fish and clams noted above (although, of course, I did not think of it in those terms
at that time). I spent a year or so getting used to my new administrative tasks and
then I turned my attention to another item in my job description, research. But three
events occurred within several weeks at the beginning of my first year at ECU. The
low-lying land of eastern North Carolina was hit in quick succession by three hurricanes, Dennis, Floyd and Irene. The result was terrible floods that affected the
region for several years (Figs. 4.1 and 4.2).
We’ve had enough hurricane hits along the Gulf and Atlantic coasts of the US
over the past decade or so to know that some hurricanes are mainly rain events (such
as Floyd), some are wind events, and some are storm surge events. Some terrible
storms combine all three characteristics to horrifying effect. The Floyd floods
affected me personally – my wife, my two children and cat, newly arrived from the
UK, had to inhabit a hotel room for five months, living out of our suitcases until we
S. J. Culver