Guest Essay by Kip Hansen — 31 August 2024
On the U.S. Atlantic Coast and the Gulf Coast, we find Barrier Islands:
“Barrier islands are a coastal landform, a type of dune system and sand island, where an area of sand has been formed by wave and tidal action parallel to the mainland coast. They usually occur in chains, consisting of anything from a few islands to more than a dozen. They are subject to change during storms and other action, but absorb energy and protect the coastlines and create areas of protected waters where wetlands may flourish. A barrier chain may extend for hundreds of kilometers, with islands periodically separated by tidal inlets.”
There are several important things to know about barrier islands:
1) There are made of sand. Often on the ocean side they have sandy beaches and sand dunes, behind which are flatter areas of sand leading to the semi-enclosed lagoon.
2) They have been formed by wave and tidal action, and are re-formed by the same natural forces. (There are several theories of how the come into existence.)
3) They are subject to change – by the very same forces that created them: waves, currents, and storms.
Barrier islands, when left to their own devices, make wonderful places to visit – by car if there are roads and by boat when there are no roads.
They seem so nice, in fact, that beach loving humans have even building entire cities on them for more than a century.
Now, a reasonable person might think that building a city on a low-lying spit of sand at the ocean’s edge is a rather foolish thing to do. After all, barrier islands are by definition “subject to change”. That is, the sand both washes onto the barrier island and washes away from the barrier island. The wind and waves remove parts of barrier islands and move them elsewhere. Whole islands can move along the shore in what is known as longshore drift.
The USGS’s Earth Resources Observation and Science (EROS) Center has a very well-done illustrative series of satellite images showing the changes of the barrier islands off of Chatham, Cape Cod, Massachusetts. Check the link and click through the images in time order. Then imagine, instead of bare sandy beaches, the island had been covered, like so many others are, with homes and businesses.
The island, as its name implies, is a barrier between two bodies of water – the ocean/sea and an enclosed (semi-enclosed) body of water. The backshore (facing the continent) semi-enclosed bodies of water have many different names such as “bay”, “river” (incorrectly), “sound” and “lagoon”. Not all barrier islands are strictly islands, are not entirely surrounded by water, some have minor connections to the main body of land and a larger number have been connect to the main shore with causeways and bridges.
Sea level, slowly and steadily rising in most parts of the world at the present time, is not a major concern for barrier islands. This is true despite the clamor of alarm from the climate crisis crowd. The tiny annual rise of the sea’s surface, measured in single digit millimeters, goes entirely unnoticed by the dynamical system that creates and destroys barrier islands.
Remember: “They [barrier islands] are subject to change during storms and other action, but absorb energy and protect the coastlines and create areas of protected waters where wetlands may flourish.” [ source ]
Barrier islands do not protect the coastlines on purpose – nor do they create wetlands. The protection is a byproduct of the dynamics of the energy of ocean waves, tides, and storms (increased energy) that builds the barrier island. Wetlands develop on the backshore of the islands and on the shoreline behind barrier islands as the sediment from the land builds up along the shore and is no longer washed out to sea by waves and strong tides – both prevented by the existence of the barrier island.
But the same forces that build barrier islands also alter and destroy them – one piece at a time.
The greatest U.S. disaster involving a barrier island was the Galveston Hurricane of 1900. “Galveston [Texas] is built on a low, flat island, little more than a large sandbar along the Gulf Coast. …. development activities on the island actively increased its vulnerability to storms. Sand dunes along the shore were cut down to fill low areas in the city, removing what little barrier there was to the Gulf of Mexico.” [ source ] Over eight thousand lives were lost (6,000-12,000) and the city was nearly totally destroyed. Galveston, Texas did not learn its lesson, as evidence by the Google maps satellite view here. Before that, the Texas city of Indianola was destroyed by a hurricane in 1875, rebuilt, and then destroyed again by a hurricane in 1886. It is a ghost town today.
Ocean City, Maryland is said to have benefited from a massive storm in 1933:
“However, the most historically significant change in the storm-ravaged resort was the existence of a new 50-foot wide, eight-foot deep Inlet at the south end of town. The huge waves that pounded the east side of the resort combined with the massive amount of water that built up in the back bays conspired to cut the Inlet and separate the southern end of the town from what is now Assateague Island.” [ source ]
A number of homes and business were swept out to sea an the new inlet caused the loss of continuous access to the southern portion of the island creating what is today called Assateague Island. The good news was that the new inlet allowed the fishing community, on which the area depended for income, to get their fishing boats from the bay to the ocean and return. Before the storm, fishermen were forced to drag their boats with teams of horses from the oceanfront beach across the island to the bay.
The cutoff southern portion of the island is now the famous Assateague Island National Seashore, with fabulous beaches and roaming herds of wild horses.
Now, consider the consequences of such a natural event if it was to occur today at a slightly different portion of what is Ocean City:
Like in Ocean City, sometimes the ecological outcome of a strong storm rearranging or cutting a barrier island has positive effects:
“Barrier islands like Fire Island are known as early successional habitats [pdf], which means they require regular disturbance events to keep their ecosystems in check. Under normal circumstances, Fire Island would experience disturbance events on an annual basis. However, engineers have gone to great lengths to stabilize the island, and now only powerful storms like Sandy are able to have a significant impact on the island’s ecosystem.”
“Barrier islands are very dynamic systems, they don’t stay the same from one year to the next. The species that inhabit them there are adapted to these changes, so if we try to keep these systems static, we are going to lose these species,” said Dr. Cohen [assistant professor at SUNY College of Environmental Science and Forestry ].“
The major threat to all of these cities built on low-lying barrier islands is storms with high winds and strong waves. These forces wash away sand dunes, lowering the overall height of the island, and drive water through low elevation areas, often all the way across an island forming a cut. Sometimes the water comes from the bay side of a barrier island, as a storm blows more and more water into the bay, the lagoon, on the shoreside of the island. The excess water then seeks out a path back to the sea. When it finds a downhill path to the sea, it runs through it, cutting away the sand, the land, faster and faster as the water flows through. This is what happened at Ocean City, MD in 1933, which is clearly visible in the photo of the new inlet (far above). The same occurred at Fire Island, NY.
Not all long thin islands off the Eastern Seaboard are, strictly speaking, sand-based barrier islands. Some, such as Miami Beach, are remnant limestone/coral reef systems subsequently covered with sand. These types of islands will suffer from waves and wind and surface erosion, but are unlikely to have new inlets created.
When we speak of a storm forcing water into a bay, we should think of New York City during the remnants of Hurricane Sandy, which raised water levels in New York Harbor and up the Hudson River by as much as 12-14 feet. Many factors were involved in that event, among them the restriction of access of the rising water to the Meadowlands, the natural bioswale for the excess water.
Bottom Lines:
Almost all mass media outlets focus primarily on sea level rise when covering threats to barrier islands, with storms (hurricanes) secondary. This is, of course, a misleading picture. Sea level rise is a slow minor issue.
Storms, with their energetic wind and waves, push almost unbelievable amounts of water at high energy against the shore – whatever is there has to deal with all that mass moving at speed hitting those stationary objects.
That water moves sand, soil, building, trees—whatever is there. That water builds up in bays and lagoons and seeks release to a lower elevation – and it is this that cuts barrier islands, forming new inlets. And it is then, when water is rushing into or out of a bay, that major geomorphic changes occur. One island becomes two, a long island is shortened, a short island is made longer, an entire island moves hundreds of yards up or down the coast or its end becomes a hook. The human developments on those islands are of little consequence, unable to mitigate or resist the tremendous forces being applied.
Building permanent structures or infrastructure on impermanent, or ephemeral, barrier islands is a serious societal error. These islands should all be allowed to revert to their more natural states, used as beaches and National Seashores. Rebuilding after storms should be forbidden.
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Author’s Comment:
This has all been said before. The lessons of Galveston, Ocean City and Indianola (Texas) have been ignored and cities built on the “here today, gone tomorrow” barrier islands of the U.S.’s Atlantic and Gulf Coasts.
Historically, we are almost at the height of the Atlantic Hurricane Season, which statistically is the second week of September.
As I showed in a recent essay on Atlantic hurricanes, it is only a matter of time before a hurricane barrels ashore on one of our barrier islands covered with condominiums, homes, highways and businesses. Hurricane strength and path, direction and speed of winds and state of the tide at landfall will determine the extent of the disaster.
Thanks for reading.
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Perhaps they didn’t learn the correct lesson, but a lot of effort was made to raise the height of Galveston Island, in addition to construction of its sea wall and granite jetties.
Scissor ==> That’s True….but they have not done so for the entire island, nor have they done the same for the other cities built on the barrier islands of Texas.
If you are not familiar with this issue, use Google maps, in satellite view, to travel along the Gulf Coast and the Atlantic Coast — use a close enough view to see just how many of those low-lying sand islands are covered with high-rise condos, highways and homes.
Yeah, I agree that development in such places is crazy.
I had a friend with a beach house (built on stilts basically) on the west side of Galveston Island. He was self insured and in a good enough financial situation to be able take on the risk. Not my cup of tea.
In any case, some people don’t mind living in Dodge but my advice is know when to get out. My friend passed away several years ago and his beach house still stands.
Building communities on inland flood plains is a very common similar human foible .
The reason that cities and towns have routinely been developed on inland flood plains and marine barrier islands, as well as on coastal bays and harbors, is because this is where people want to be. For purposes of views and water recreation, and for communication and trade. Thus these lands are also the most intrinsically valuable and therefore the highest priced lands around the world.
It is no accident or coincidence that most of the largest and oldest cities in the world are located on harbors and protected bays of coastal areas, or along major navigable rivers. That’s where trade concentrates, so that is where people live and conduct business.
So there is no point in tut-tutting that it is silly, wasteful, and dumb to put human development in areas threatened by flooding. That’s where development always has taken place as a first priority over non-water accessible locations.
Even if one believes that with today’s modern transportation infrastructure that being close to water should no longer matter, it still does. Most world trade today still travels by water for part or most of the journey between sellers and buyers. And people will always highly value scenery, and thus value scenic lands the highest.
So given all that, dealing with flood potential is merely part of the cost of living and doing business in waterfront areas including barrier islands and bayfront shoreline. Investments designed to protect against flooding – sea walls, revetments, raising structure first floors, dikes and levies, flood control dams, etc. – along with other associated expenses like flood insurance policies, higher property taxes, special assessments … are just the cost of being there … as well as the risks associated with being there.
Mississippi?
Oh, we’ve entered the second phase.
I. Sea levels don’t rise
>> II. Sea Levels rise, but it’s not a problem <<
III. Sea levels rise, it’s problematic, but too late to do anything anyways
Your conception of reality it faulty. Sea level has been rising most recently for roughly ten thousand years, and people have been fighting back at nature for longer than that, e.g., reclaiming land.
Engineering, use of dikes, pumps, etc., for example in the Netherlands for hundreds of years, allow mankind to reclaim and flourish on land that is below sea level.
The human spirit and nature is often in conflict, such is life.
Remember the sinking Maldives? Give us your climate cash…
Well…
Atoll Estates has announced Zamani Islands, a new destination in the South Malé Atoll, Maldives. This development will include the region’s first superyacht marina and yacht club. Launching its first phase in Spring 2026,
https://www.superyachtcontent.com/the-crew-mess/superyacht-shipyard-and-marinas/zamani-islands-maldives-first-superyacht-marina-to-begin-construction-in-2026/
Name one person on WUWT who has ever said sea levels don’t rise
To be honest, the late John Daly did.
Did John Daly comment here?
Not a severe problem if idiots don’t build in stupid places.
Same as building on known floodplains.
Guess what… there is a good chance you might get flooded !
Then some idiot will say “but it hasn’t flooded here for 100 years!”
These aren’t stupid places to build. Coastal areas including barrier islands, bayshores, rivers, etc. have always, throughout the history of human civilization, been the most valuable lands. Because most trade, not just historically but even now, travels largely by water .. and because water views have always been highly valued. Nothing stupid about that. That there are risks involved is nothing new, and today’s modern infrastructure solutions have done much to mitigate the damage of flooding. Insurance also helps to mitigate the risk as well.
Some of those coastal areas might be find for building but not all. Insurance doesn’t mitigate the risk of damage and injury- only financial, and in such areas, the people there should be paying into a pool, not those on high ground inland.
Building on flood plains without proper engineering is stupid.
We do have a national flood insurance program in the US. If your property is located within a 100 year floodplain you are required to obtain flood insurance, which is paid for out of the pockets of those insuring against flood. If you want to obtain any financing or get a building permit, it’s mandatory. If you do not live in the flood plain, then you don’t pay on your insurance.
As far as flood mitigation engineering goes, it depends upon site specific needs. Sometimes the risk can be mitigated with a levee or dike, but of course levies and dikes can fail (see New Orleans, 2005) … and of course hundreds if not thousands of flood control dams have been erected throughout just the US alone. Or it might be a matter of building higher. In days past it was not uncommon to bring in fill to sites within the floodplain to raise structures above the anticipated flood elevation. But the problem with that method is you end up forcing the waters onto someone else’s property upstream, so most jurisdictions restrict or prohibit doing that.
Beginning in the 1940s, the Army Corp of Engineers came up with a plan to build hundreds of flood control ponds and lakes along the tributaries of the Connecticut River. Some got built- but then the enviros fought to stop it. One of the earliest was built near me in north central MA. It’s very popular with the enviros, greens and everyone else for kayaking. The lake and 200 acres of forest next to it are owned by Interior. Of course if any flooding now occurs in these tributaries, everyone will blame the government for not doing anything to prevent it- and few people will even understand that there was a plan.
But essential is the risk be recognized and mitigated. Elected officials in Abbotsford BC did not – so when the Nooksack River overflowed in 2021 dikes failed, because they had not been properly maintained despite a warning from the Nooksack in 2000.
The Sumas Prairie was a lake decades ago.
If water leaks through or goes over top of earthen dikes they will fail.
Yes, the risk mitigation has to be rational and well managed. The principal issue that resulted in the flooding of much of New Orleans as a result of Hurricane Katrina was poorly designed/built levies that failed. There actually was not that much storm surge from Katrina in NO (the strong side of the storm was well east in MS and western FL), but it didn’t take much surge to cause the levies to fail. It appears that the poor condition of the levies was a result of the endemic government corruption in Louisiana, particularly amongst the levy boards.
Duane ==> You may be mixing up “water views”, which are more valuable, with building on barrier islands made of sand. It is not the inherent risk of waterfront property, it is the inherent risk of building on ephemeral barrier islands.
Flood plains are another equally foolish place to build.
What an incredibly stupid comment !!!
Showing absolutely zero comprehension of anything related to reality.
Sea levels rise and fall continually and always have ever since Earth acquired its oceans …. particularly so since the onset of the Pleistocene 2.6 MYA with its ongoing cycles of glaciation and interglacials. The only people who seem to “deny” that are you warmunists. Climate change realists know and acknowledge actual real science like that.
Sea levels change slowly however, with even the fastest rates of SLR since the beginning of the Holocene being only a few cm/yr, while current SLR. is only 2-3 mm/year. The infrastructure of today’s cities is mostly less than 200 years old, with most of today’s largest seaside cities being mere villages or towns as recently as one or two centuries ago. Here in the US most bayfront and oceanfront homes much over 30-50 years old are being torn down and replaced with new far more flood resistant homes – due to the rapidly escalating values of waterfront real estate.
With any plausible SLR, there is more than ample opportunity for human society to adapt and recycle our waterfront development at a normal rate without any of the rash, radical, and stupid upsets that the warmunists now demand.
Facts of tide gages collated at PSMSL.org show only continuation of a slow rise since the end of a cool era circa 1750AD.
(Land rising and subsiding has a greater effect on tide gage readings than temperature.)
Facts from geology show great change in sea level during and after the last real Ice Age.
Fun fact: there are fish species in the upper Peace River system of northeastern BC that match those in the Great Lakes.
As the ic e sheet was melting a huge lake formed, encompassing both areas. Eventually it drained, fish remained upstream of narrow Peace Canyon with its turbulent water flow. (Power dams came much later, at some point the Rocky Mountains rose in height, one river that flowed south into the Fraser now flows north into the Peace.)
Leave the barrier islands undeveloped? Too late for that. Some of my favorite memories have originated on the many barrier islands of New Jersey. True, the homes and infrastructure on these developed islands are at serious risk. The owners of these properties have taken on that risk, and most are prepared to fully rebuild as necessary to maintain their beachfront domains. The homes destroyed by storm Sandy were almost all rebuilt within 3 years. I know of several owners who self insured and rebuilt with their own funds. It was worth it to them.
Yeah, people roll the dice all the time, sometimes they lose.
My visits to Galveston spanning five decades made a lot of memories, like your visits to NJ barrier islands. I’ve stayed at the majestic Hotel Galvez on Galveston that is well over 100 years old, sitting just across from the sea wall.
I was in Galveston a few times just before tropical storms or hurricanes shut it down, but my visit there on 11 September 2001 was most impactful to me.
Hurricanes can cause serious damage in the short term, but many coastal communities struck by storms thrive afterward. Galveston today, post Hurricane Ike, is fresh and vibrant. Many old decrepit structures in need of replacement were destroyed, followed by a building boom, modernization and storm hardening. The author’s conclusion that building on barrier islands is a serious societal error is arguable.
A better conclusion would be that one should not be surprised at the vulnerability of barrier islands and plan development accordingly. Beachfront lots on Galveston Island sell for as much as several $million/acre, sometimes substantially more than the value of the home that is built there.
One also has to account for “Hurricane return period,” the statistical frequency of a hurricane landfall within 50 nautical miles of a given location. For Galveston, that is about 10 years for any size hurricane and about 25 years for a major hurricane. So you build to withstand moderate strength storms and hope for a good 25 year run. It is in fact better than that, because the NOAA definition doesn’t account for quadrant of the storm that strikes a location. Glancing at the NOAA maps ( https://www.noaa.gov/stories/what-are-chances-hurricane-will-hit-my-home), it looks as though the most vulnerable locations also tend to be the most prized and valuable real estate.
“The owners of these properties have taken on that risk,…”
no insurance?
John ==> You state the obvious advantage of the privileged classes and a wealthy economy. Some of your acquaintances were wealthy enough that they could absorb the lose of a home and rebuild.
Many of the others were rebuilt through the largess of various government programs — meaning the taxpayers paid for the privileged few to rebuild homes on the Jersey shore.
Had Sandy been a Cat 4 or 5 hurricane, traveling in a different path, and hit the Jersey shore head on, or worse, the eye traveling north along or just off the shore, city after city would have been nearly totally destroyed.
The Jersey shore simply “lucked out”.
Re-imagine the story of Sandy in a Third World capital with an equal population of 1.5 million people living on a sand bar.
PS: My wife, who grew up in a well-to-do East Coast family, spent many happy summers in a rented house with her family on The Shore. Father would come down Friday afternoon and spend the weekends returning to work Monday morning.
I have been on, driven on, vehicle stuck on a couple until I learned about them, many of these islands and even studied the effects of tropical storms small and large. Geologists learned long ago that the islands and the estuaries they partially protect are ephemeral. It takes a great subsidy to live on them and many of these may ultimately become bankrupt. Insurance companies have been realizing this, governments, real estate businesses, and too many individuals not so much.
Louisiana is building, they hope, a new Mississippi River distributary to the Gulf. Interesting experiment. These islands have a fascinating history, a subject of which we are losing too much.
hdhoese ==> Yes, the most slaient feature of true barrier islands is their impermanence — there “here today, other there tomorrow, and gone next year”.
In my opinion, the US Federal government should quit paying for disasters caused by building and rebuilding in harms way – barrier islands, known flood plains, filled marsh, etc.
Tornados, hail, blizzards, lions and tigers and bears, oh my. Can’t people have some fun, or do the socialists have to take it all away through “central planning?” What happened to liberty and freedom?
The freedom to do those things — without federal taxpayer assistance — does not see like a loss of freedom to me. It is rather more freedom for those not required to pay for the benefits of those who choose to build and live there.
pflashgordon ==> I am a strong supporter of personal responsibility. If people want to build homes in areas almost certain to be destroyed by natural forces, let them do so. But do not let them demand that my taxes replace their home when disaster strikes.
The equation changes slightly when considering things like publicly owned property — a barrier island which is currently state owned.
Further, certain natural resources, such as rare habitats and undeveloped beaches, can and should be preserved for the enjoyment of all. National Seashores and the like.
Calling for the restriction of rebuilding is done in the same spirit that governments have building codes and zoning laws. Declaring a flood plain a “no rebuild” zone is simply a sensible thing to do.
FEMA and state assistance are not blank checks, and no assistance is provided for vacation homes, only primary residences. Assistance is supplemental to insurance, and recipients are required to obtain and maintain insurance in the future. When a disaster is declared with estimated losses of, say $10 billion, I would be interested to know what % of that is typically paid out by the government versus insurance or private funds. Does anyone know?
American’s are traditionally kind and generous toward people in true need. It is rather harsh to say that storm victims “demand” to be rebuilt. They ask (apply), and must meet government criteria, and the aid is not limitless. If we don’t agree with the criteria and amounts, and we deem them to be too generous, then work to change it.
While some gormless people move to the coast and suffer the consequences, many do so as a result of calculated decisions, eyes open.
The point of your excellent article is that slowly rising sea level is not the problem with barrier islands, so climate fanatics shouldn’t scream “climate change” at every storm.
You could add New Orleans to the list. Most of it is below sea level in a hurricane prone area.
Someday, the Atchafalayla will have its way.
The five canals New Orleans uses to pump water to the north should be cut all the way through the city to the south to allow more free flow of water and the sediment it carries to rebuild the land south of the city. Erosion and subsidence are what’s removing the land that was built up by the Mississippi River. Containing it and forcing the majority of the river to exit through an eastward channel are what has made much of New Orleans sink below sea level.
We can blame the mess on Jean-Baptiste Le Moyne de Bienville who thought a tidal mudflat barely above sea level was an ideal place to found a city named La Nouvelle-Orléans.
Human success and the efficiency of social development depend critically on whether people think more about what they will have for lunch or about what their lives will be like in 30 years based on decisions they make today.
Andy ==> Humans, according to the wisdom of the ages recorded in the world’s religiousand philosophical books, Eastern and Western, have always faced the temptations of greed and personal aggrandizement — seeking riches and fame today — ignoring the long-term result.
seize the day for tomorrow you may be dead
Hurricanes have reshaped islands in the Great Lakes as well, when they are just sand. Take Toronto Island: It was a spit of land until a storms in 1852 (filled in with silt) and 1858 made it an island. Then there are the various sand dunes and points along the coasts and the lakes that change with the wind and water. People seem to want to take the risk for the pleasure of being by the water.
The Expulsive ==> And people are welcome to risk their money and efforts for the pleasure. My wife and I lived what could be said a dangerous life-style, on our sailboat in the Northern Caribbean for more than a decade (where we did various charitable and humanitarian projects). We felt it was worth the risks (but we were very sensible and seriously careful sailors.)
The problem arises when a society allows these risks to be born by those who do no get the benefit — allowing the pleasure seekers to pay for their mistakes with other peoples money.
OPM, in all of its multitudinous forms, is the largest motivator of all times. The modern Democrat Party has raised the art form into a vehicle for permanent control of not only government but of society in general.
Thanks Kip. I much enjoyed this post.
(not the formatting, though — or maybe my computer messed it up)
We visited Jekyll Island (70 m south of Savanna) in 1968 and converted our book-learning into first-hand information.
John ==> Ah — formatting. Yes, there was something very wrong with the original formatting, which puzzled me and took me some time to figure out and correct.
Traveling in the ICW and visiting the eccentric little communities on the barrier islands is fascinating — we always skip the tourist destinations.
Jekyll Island is classified as a barrier island though it doesn’t have the long skinny profile more common to the type. We have sailed past Jekyl in the ICW only once in our years of traveling up and down the East Coast — we usually sail offshore in the Atlantic past Georgia — north or south.
Assateague sand has formed the southern hook that created Tom’s cove. That same sand has made Assateague Light a mile from the ocean now. I can’t wait to see what CO2 does next with Assateague.
Like Sarichef Island in Alaska, which is moving, not shrinking
Kip. Another problem is that of sand migration and submarine canyons. Sediments tend to move along the coast over time in the direction of prevailing currents. That is until they reach a canyon whereupon they tend to drop into the canyon and find their way outward down the continental slope. Those canyons are quite numerous worldwide. Something like 13 of them I’m told between Hatteras and the Gulf of Maine.
Not that big a deal as long as there’s a source of new sediment as there was until about a century ago. But flood control and river navigation efforts on major waterways like the Mississippi as well as smaller streams often substantially reduces the flow of sediments to the sea. This is quite evident in the Mississippi Delta which is losing 3000 or so acres of land every year to the Gulf of Mexico. But it’s happening lots of places, I doubt that in the long term that’s going to bode well for barrier islands.
One catastrophist Jurko showed a photograph of what he said was a town on he US east coast in an area of more stable barrier islands – but in fact was of flooding in Texas with a photograph of the town sign grafted in.
Of course flooding will occur if dikes are not properly maintained:
New Orleans has five canals used to move water north, out of the city. Until 2005, all but one of the pump motors were antique, open frame style. One had been replaced with a modern, sealed motor. When Katrina breached the dikes and canal walls, those pumps were flooded. The antique motors shorted out, the modern one kept running.
But the pumps were useless because while they were running, the water they pumped into the canals ran right back into the city through the breaches in their walls.
What should be done is cut those canals through the city to the south and pump drainage water formerly forced north into them to flow south to the gulf. That would allow sediment to flow through the city to start rebuilding the eroding / subsiding tideland and river delta.
Another project that should be done is raising the below sea level parts of the city. A large part of Seattle, Washington, was elevated in the 1890’s. It can be done now with New Orleans.
Chicago was raise also.
There’s a whole string of islands down the US east coast.
There’s a settlement near Melbourne FL built on a a barrier island, Cape Canaveral is on another.
The Wright Brothers did their initial testing on North Carolina’s Outer Banks, near Kitty Hawk town whose elevation is 7 feet. Outer Banks – Wikipedia
(I understand that much of the east coast of the US is sinking from plate tectonics, other locations in the world such as parts of SW BC/NW WA are rising (the plates are smaller there).)
Very informative Kip.
Made me think of Pat Conroy’s book, “The Water is Wide”:
Youtube movie: “Conrack” https://www.youtube.com/watch?v=VYQt7xK7IT0