Along the East Coast of the US, especially in the Outer Banks and Intracoastal Waterway areas, there are problems with coastal erosion. The currents along this middle to southern section of the East Coast can be very strong. The implications of this are the gradual loss of beach area in some locations and many deposits of sand onto other beach areas.
In this commercial age, the diminishing sand and the encroaching waves would mean the loss of beachfront property and business in the tourism economy. Business owners and property owners placed pressure on governmental organizations to find a solution to the erosion problem. What they didn't realize is that the solutions they could think of would either cause new problems or would not permanently fix the current problem.
One of the ideas the government had was to relocate the already relocated sand. By dredging up sand that was deposited on some beaches and taking it back to the eroded beaches, governmental organizations figured this would at least help the problem. This process is expensive and has to be repeated often. However, that's not the main focus here.
Officials decided to build jetties. The purpose of the jetties, and the assumption behind them, was to block the erosion of the sand. The whole premise is that even if the sand is eroded down current, it will be stopped by the man made jetty jutting out into the current. This does make beaches an interesting shape because it is not actually stopping erosion in the first place, it is merely preventing the sand on the beach from getting very far.
What individuals failed to realize (or didn't put much store in) was that by altering the shape of the coastline, they were also altering the flow of the coastal currents. The currents are not going to stop just because something is in their way. Instead, the currents then flow around the jetty, and more sand is eroded from the opposite (down current) side of the jetty. As a result, a new jetty had to be built to prevent the erosion of the down current beach. This, as is probably obvious, is a continuing cycle of erosion and erosion prevention.
The mental model of the officials and others in the community was that by placing something in the flow of the current, the erosion from the beaches would be stopped. This mental model was insufficient because it failed to take into account where the currents would go after they "ran" into the jetties. Because nature doesn't necessarily move tremendously fast, the new coastal erosion was probably a delay in the real world model. As a result, for awhile the mental model of these individuals was confirmed when the sand from the beaches was stopped at the jetties. By the time the deficiency in their thinking was realized, it would have been too late to change the plan. Thus, more and more jetties built.
I had this idea from multiple classes in undergraduate work. I wasn't sure where to cite sources as a result. It's all what I remember from class. I can thank the James Madison University Department of Geology and Environmental Science.
In this commercial age, the diminishing sand and the encroaching waves would mean the loss of beachfront property and business in the tourism economy. Business owners and property owners placed pressure on governmental organizations to find a solution to the erosion problem. What they didn't realize is that the solutions they could think of would either cause new problems or would not permanently fix the current problem.
One of the ideas the government had was to relocate the already relocated sand. By dredging up sand that was deposited on some beaches and taking it back to the eroded beaches, governmental organizations figured this would at least help the problem. This process is expensive and has to be repeated often. However, that's not the main focus here.
Officials decided to build jetties. The purpose of the jetties, and the assumption behind them, was to block the erosion of the sand. The whole premise is that even if the sand is eroded down current, it will be stopped by the man made jetty jutting out into the current. This does make beaches an interesting shape because it is not actually stopping erosion in the first place, it is merely preventing the sand on the beach from getting very far.
What individuals failed to realize (or didn't put much store in) was that by altering the shape of the coastline, they were also altering the flow of the coastal currents. The currents are not going to stop just because something is in their way. Instead, the currents then flow around the jetty, and more sand is eroded from the opposite (down current) side of the jetty. As a result, a new jetty had to be built to prevent the erosion of the down current beach. This, as is probably obvious, is a continuing cycle of erosion and erosion prevention.
The mental model of the officials and others in the community was that by placing something in the flow of the current, the erosion from the beaches would be stopped. This mental model was insufficient because it failed to take into account where the currents would go after they "ran" into the jetties. Because nature doesn't necessarily move tremendously fast, the new coastal erosion was probably a delay in the real world model. As a result, for awhile the mental model of these individuals was confirmed when the sand from the beaches was stopped at the jetties. By the time the deficiency in their thinking was realized, it would have been too late to change the plan. Thus, more and more jetties built.
I had this idea from multiple classes in undergraduate work. I wasn't sure where to cite sources as a result. It's all what I remember from class. I can thank the James Madison University Department of Geology and Environmental Science.
Nice topic Rebecca. I think what's unclear here is:
ReplyDeleteWhat is the difference between the variables "Costal Erosion" and "New Erosion"? for me, they look the same, or, can lead to one another.
I did think about that and wasn't sure if my loop should go back into coastal erosion. The thing is, the new erosion wouldn't have happened without the building of the jetties. That's why I created multiple variables.
ReplyDelete