Category Archives: Beach of the Month

Beachfront Development along the Pacific Coast of Colombia: A good thing? By Orrin H. Pilkey & William J. Neal

By Orrin H. Pilkey and William J. Neal

Although it seems to defy logic, building a home right next to an eroding beach may be a good idea in some cases.

When the two of us, along with Jaime Martinez and Juan Gonzalez, were studying the Colombia’s Pacific Coast barrier islands, we visited a couple of small villages perched on the edge of rapidly eroding beaches (Martinez, et al., 1995). In one instance we watched as a house was being dismantled to be moved back. Local people told us that two men could dismantle and move most of the village houses in a matter of weeks (figure 1). At the time, they were keeping the village in the retreating back-beach position, yielding to beach retreat of a few meters per month due to extra high spring tides during an El Niño (figures 2 and 3).

We described the nature of these beautiful tropical beaches in our August 1, 2011, Beach-of-the-Month article.

Although there is a good sand supply coming via rivers from the nearby Andes Mountains, a combination of high wave energy, sea level rise due to global climate change, regional effects of seismic activity and El Niños, and local subsidence, cause beach retreat (shoreline transgression).

… At first the high-risk location of these villages didn’t make any sense to us. Why should the locals live so dangerously?”
—Orrin H. Pilkey and William J. Neal

The black to dark gray sandy beaches are littered with fallen trees, drift wood, and wrack lines of flotsam. Stands of mangrove forest that grew behind barrier beaches are now dead or dying (Figure 4).

At first the high-risk location of these villages didn’t make any sense to us. Why should the locals live so dangerously?

After a few days, however, we began to understand. Living in such a remote area, the villagers had no means of communication with the outside world, no phones, and no radios. The law and medical help were a long way away. Malaria-transmitting mosquitoes inhabit the nearby rain forest.

Ivan Correa and Juan Gonzalez summed up the reasons for such village sites in their 2000 article.

• The villagers know at any time the sea and weather conditions, in order to plan activities.

• The possibility exists of having eye contact with fishing teams at a short distance offshore (in dugout canoes).

• Being aware of travelers along the coast allows villagers to be able to provide or to demand
assistance in an emergency, especially useful because of the lack of radios.

• A minimum tourist infrastructure had been developed as a source of income, an important
alternative, considering that the two main economic activities, fishing and timber, were
becoming increasingly difficult.

• Directly facing the sea takes advantage of the sea breeze for a more comfortable climate and
especially to keep malaria-transmitting mosquitoes away.

Erosion rates along this coast are sporadic. Periods of stability of a few years are followed by catastrophic erosion and/or transgression rates resulting from earthquakes on the adjacent continental shelf (e.g., Tumaco, 1979) (See Correa and Morton, 2010, for a review of Colombia’s Pacific Coast). On Soldado Island along the central portion of the coast, we found that local sea level rise could be as high as 10 feet per century. As noted above, times of El Niño also accelerate the erosion rate.

Different strokes for different folks. In the remote Pacific coast of Colombia, beachfront development has been a necessity. But even there in a subsistence economy that depends on being next to the sea, the rising sea level is changing this option. As Correa and Gonzalez note, the village of El Choncho that had persisted for 91 years, being moved laterally or back from the retreating beach as necessary, finally had to move inland to a higher elevation in 1997. The move, however, was facilitated by the fact that all of the dwellings were built in such a way that they could be easily disassembled and reconstructed in a short period of time, and at a low cost.

… In a time of rising sea level we can only view such beachfront development as imprudent and irresponsible.”
—Orrin H. Pilkey and William J. Neal

Not so in the first world where beachfront development is placed in high-risk zones by choice, rather than necessity, and increasingly using construction that does not favor being easily moved out of harm’s of way in the future.

Even though widespread awareness of the importance of impending sea level rise is only a couple of decades old, post WWII beachfront development in the first world usually took place on shorelines that were clearly retreating.

In a time of rising sea level we can only view such beachfront development as imprudent and irresponsible.

References
Correa, Ivan D. and Gonzalez, Juan Luis, 2000, Coastal Erosion and Village relocation: A Colombian case study: Ocean and Coastal Management, 51 – 64.

Correa, I. D., and Morton, R. A., 2010, Coasts of Colombia: U. S. Geological Survey.

Martinez,J., Gonzalez J., Pilkey, O.H. and Neal W.J, 1995, Tropical Barrier Islands of Colombia’s Pacific Coast: Journal of Coastal Research, 432 – 453.

Colombian Pacific Beaches at the Mouth of Bahia de Buenaventura, By Orrin H. Pilkey and William J. Neal
Among the world’s most remote beaches are those that line the 62 barrier islands of Colombia’s Pacific Coast. Only two roads lead over the Andes to access points from which the islands and their few, very small, subsistence coastal villages can be reached by boat.

Padre Island National Seashore, Texas; By Katie McDowell Peek

By Katie McDowell Peek, Program for the Study of Developed Shorelines / Western Carolina University

Stretching 80 miles along the Texas shore is Padre Island National Seashore, the world’s longest stretch of undeveloped barrier island. Padre Island is located along the Gulf of Mexico in southern Texas about 50 miles north of the US/Mexico border (Figure 1).

In addition to being 80 miles in length, a large portion of the island is well over two miles in width and contains elevations up to 50 feet. Because of its size, Padre Island National Seashore preserves many unique coastal environments, including complex dune systems, coastal prairie, wind tidal flats and a hypersaline (salty) lagoon environment known as the Laguna Madre.

The dunes & coastal prairie
The dynamic dune system on Padre Island is quite impressive with dune heights up to 50 feet above sea level. The fore-island dune ridge system (high dunes running parallel to and just back from the beach) is the most continuous dune system on the island and also boasts the highest dune heights (Photo 1). Although these dunes are dynamic features shaped and reshaped by winds and storms over time, most of the dunes behind the fore-island dune ridge have stabilized due to the vegetation (Photo 2).

The coastal prairie (also known as grasslands) environment makes up the majority of the islands area, and consists of low areas and small ridges covered by vegetation. This part of the island is home to many plants and animals, including birds, reptiles and mammals (Photo 3).

The lagoon and wind tidal flats
Two environments of Padre Island National Seashore that are closely linked are the wind tidal flats and the Laguna Madre. The Laguna Madre (Fig. 1) is a shallow hypersaline (salty) lagoon that separates the island from mainland Texas. The lagoon is extremely important both ecologically and economically, as it is the home to an enormous population of fish, shrimp, crabs and birds. The wind tidal flats adjacent to the Laguna Madre are the island’s primary wetlands (Photo 4). These flats are only periodically flooded by northerly wind tides and therefore are dry for a large portion of each year. Although these ephemeral marshes may appear barren to the casual observer, this portion of the island is extremely biologically active.

… The beaches of Padre Island are themselves unique because of the long stretch of uninterrupted coast that has not been developed….
—Katie McDowell Peek

The beaches
The beaches of Padre Island are themselves unique because of the long stretch of uninterrupted coast that has not been developed. The beaches are feeding and nesting grounds for many different species of birds and both the threatened green sea turtle and the endangered Kemp Ridley sea turtle use the beaches for nesting. Unfortunately, beach dr

Cumberland Island National Seashore, Georgia USA; By Chester W. Jackson Jr. & Carol Ruckdeschel

By Chester W. Jackson Jr., Ph.D, Assistant Professor of Geology, Georgia Southern University and Carol Ruckdeschel, The Cumberland Island Museum, St. Marys, Georgia.

With a barrier island shorescape composed of kilometers of dune ridges, expansive maritime forest, and dynamic shorelines, Cumberland Island is a complex landscape fashioned by natural processes intertwined with a history of human and non-native biological impacts. Cumberland Island is the largest (28.5 km long) and southernmost barrier island along Georgia’s coast and has a geologic framework composed of Holocene sediments mostly along the oceanfront region welded to a Pleistocene paleobarrier. The Pleistocene core of the island contains some of the highest elevations of the Georgia coast and ranges from 8 to 10 meters high in areas within the northern half of the island. Migratory Holocene dunes exceeding 10 meters can be found along southern and northern areas of the island. The recreational beach is generally tens of meters wide and fronted with well-developed ridge and runnel topography exposed at low tide. The backbarrier shoreline is composed of a mixture of dense to moderately vegetated dunes and sediment banks, maritime forest, and marsh platforms.

Although most of Cumberland is undeveloped and managed by the National Park Service, there are a number of issues concerning the impacts that human activity and non-native species are having on the coastal landscape. One of the most notable changes to the coastal landscape is rapid shoreline accretion that has taken place along the oceanfront following the emplacement of a jetty at the south end of the island in 1882. Since the emplacement of the jetty at St Marys Inlet, the adjacent updrift shoreline along Cumberland advanced seaward approximately 1.6 km at a rate of 10.8 m/yr based on the current position of the shoreline in 2012.

Although most of Cumberland is undeveloped and managed by the National Park Service, there are a number of issues concerning the impacts that human activity and non-native species are having on the coastal landscape…
—Chester W. Jackson Jr and Carol Ruckdeschel

At first glance, the addition of a large area of sand along Cumberland’s oceanfront near the southern end appears to be a great situation for the island, however, modifications to the inlet system are likely enhancing rapid shoreline erosion along the backbarrier shoreline adjacent to the inlet. Erosion rates increased along the backbarrier from the Dungeness Dock/Wharf southward toward the jetty since 1882. Engineering and dredging within St Marys Inlet, coupled with the construction of a seawall along the wharf area, enhance erosion along the backbarrier shoreline. The Dungeness shoreline along the southern end of the island is one of the fastest eroding backbarier shorelines along the Georgia coast with erosion rates exceeding 1.5 meters per year in places. Erosion now threatens cultural resources managed by the NPS and is likely further enhanced by grazing activity of feral horses and hogs on the island, especially along salt marsh shorelines. The salt marsh suffers enormous damage from feral livestock. Heavy animals, such as horses, churn and chop the stabilizing marsh cordgrass, turning the area into a quagmire.

During the time of free-ranging cattle, the understory on Cumberland Island was greatly reduced and presented a park-like appearance. The cattle spent much time on the beach to escape biting insects and there eliminated the typical interdune Wax Myrtle habitat by keeping the myrtle bushes browsed to 30-45 cm (1-1 1/2 feet) in height. They also consumed other dune stabilizing vegetation which frustrated normal dune dynamics. Blowing sand was stopped by the inland tree line, but there was nothing to stop it between there and the ocean, so the system was greatly compromised. On the south end of the island where accretion was predominant due to the effect of the jetty, primary dunes were lacking and unable to become established because of the lack of vegetation. This precluded use of that area by sea turtles, and it was not until several years after the cattle were removed that the beach on the south end was suitable for sea turtle nesting. With a 15 to 25 year maturity period, and young returning to their natal beach to nest, only recently has the island sea turtle nesting distribution begun to equilibrate between the north and south ends. In the 1970s there was rarely a nest from Willow Pond Rd. South.

Today, the movements of the shoreline and adjacent coastal features, especially noticeable along the southern portion of the island can be linked to vehicle and foot traffic in addition to grazing and trampling by horses and other non-native feral animals. Some visitors consider the horses to be part of the charm of Cumberland, however, they are a destructive force to the island’s natural landscape. However, the main attraction of Cumberland Island is its rich coastal landscape that attracted visitors long before horses, hogs, and armadillos arrived on the island.

D-Day’s Legacy Sands, Omaha Beach; By Earle F. McBride & M. Dane Picard

D-Day’s Legacy Sands

Omaha Beach Sand Retains Evidence of the Invasion on June 6, 1944
By Earle F. McBride and M. Dane Picard

Originally published in EARTH Vol. 56 (No. 6), p. 38, June 2011.All text and image courtesy of © EARTH Magazine; Copyright © 2011 American Geological Institute. All rights reserved.

Before dawn on June 6, 1944, more than 160,000 Allied troops began storming the shores of Normandy, France, in what would be the turning point of World War II.

Troops poured out of planes and off ships along an 80-kilometer stretch of coastline. More than 5,000 ships and 13,000 airplanes supported the ground troops. The battles were bloody and brutal, but by day’s end, the Allies had established a beachhead. Gen. Dwight D. Eisenhower said the operation was a crusade in which “we will accept nothing less than full victory.” Less than a year later, the Germans surrendered, and the Western Front of World War II came to an end.

Omaha Beach was the code name for one of the five Allied landing points on D-Day. The 8-kilometer-long beach faces the English Channel, and was the largest of the D-Day beaches. Today, the only visible indications of the horrific battles fought at Omaha Beach are some concrete casements above the beach and nearby cemeteries that quietly mark the thousands of lives lost.

…there is more to the legacy than just the memorials: The sand at Omaha Beach retains remnants of the devastation.
Earle F. McBride and M. Dane Picard

If you look a little closer, however, you will see that there is more to the legacy than just the memorials: The sand at Omaha Beach retains remnants of the devastation. A study of the sands revealed bits of shrapnel, and iron and glass beads that have been reworked by the English Channel’s waters over time, a microscopic record of the battle.

THE BATTLE
Capturing Omaha Beach was the objective of U.S. Army forces commanded by Lt. Gen. Omar Nelson Bradley. They numbered 34,250. The U.S. and British Royal Navies provided sea transport. Strategically, this landing was necessary to join American forces at Utah Beach to the west and British forces at Gold Beach to the east.

The Germans were ready for the Normandy invasions. In early June 1944, German forces under the overall command of Field Marshal Erwin Rommel occupied strong points along the northwest coast of France, entrenched in high ground above the beaches of Normandy. At Omaha Beach, arching bluffs as high as 60 meters offered strategic positions, and the Germans left no part of the beach uncovered. The entrances of gullies, running from the shore to the bluffs, were especially fortified with soldiers, 7,800 men of the German 352nd Infantry Division,commanded by Gen. Dietrich Kraiss. Rommel’s plan was to stop any invasion at the water line, which he and Kraiss believed was possible.

Very little went as originally planned for the Allies. Most of the landing craft missed their target; many of them never reached the beach at all. The pre-landing Naval bombardment was ineffective and likely inadequate, killing few Germans (but many cattle). Engineers struggled to remove obstacles. At Omaha Beach, for many hours, Allied troops could not get off the beach, and the landing nearly failed. It was the most tenuous of all Normandy landings. At one point, Bradley considered evacuating his forces. But in the end, the invasions succeeded. Despite losing more than 9,000 Allied forces on D-Day, the invasions opened up a path for 100,000 Allied troops to march across Europe, pushing back the Germans as they went.

THE BEACH
Forty-four years after D-Day, on the morning of June 8, 1988, we visited Omaha Beach. Like most visitors, we started at the War Memorial. The thousands of small white crosses and Stars of David evoke the ghosts of those who perished in the battle. From there, we wandered down to the beach itself.

Bound at each end by rocky cliffs, Omaha Beach is a gently sloping tidal area; on average there are about 275 meters of land between low and high water marks. The beach looks pristine. It rained the night before our visit, and it was still raining as we hiked through the sand. Fragments of mollusk shells glistened, and water ran through rills.

As collectors of sand and sandstone around the world for more than five decades, we never miss an opportunity to gather sand. So as we walked, we bent down and scooped up sand samples at the high-tide point. Little did we know what we would find when we got home and started studying the sand.

THE SAND
When we returned to our labs, we examined the sand using several microscopes: a binocular optical microscope, a polarizing optical microscope and a JEOL scanning electron microscope, each of which provides different information on grain size, shape, roundness and composition.

A thin section of the sand revealed a large number of angular opaque grains that were magnetic…we concluded that the metal and glass particles were human-made particles generated from the explosions of munitions during the Normandy landings.
Earle F. McBride and M. Dane Picard

The sand is light-gray, well-sorted, subangular to subrounded, fine to medium-grained and dominantly detrital quartz (78 percent), with about 9 percent feldspar, 4 percent carbonate grains (bioclasts and limestone clasts), 3 percent heavy minerals, and 2 percent chert and other rock fragments: Although beach sand varies widely, the sand composition of Omaha Beach reflects typical sand eroded from sedimentary rocks inland and carried to the shore by the Seine and several small rivers. But the sand also contains some artifacts that took us a while to recognize.

A thin section of the sand revealed a large number of angular opaque grains that were magnetic. Shard-like, they were only slightly rounded. Some were well-laminated. These grains were also associated with small spherical beads of iron and glass. At first, we were uncertain of what we were looking at. However, in a few days, we concluded that the metal and glass particles were human-made particles generated from the explosions of munitions during the Normandy landings. After further testing, we determined the sand does indeed contain 4 percent shrapnel and trace amounts of beads of metal and glass. Because waves and currents on any given day can selectively concentrate sand grains of a given specific gravity, we cannot be certain that our sample is representative of the entire beach, that shrapnel grains make up 4 percent of Omaha sand as a whole.

We found that the shrapnel grains range from very fine to coarse sand size (0.06 to 1.0 millime- ters) and display a variety of shapes and degrees of roundness. Nearly all of them retain their original nonspherical shapes, but all grains, even the most shard-like, have had some of their sharp edges blunted as can be expected by abrasion in the swash zone of a beach (the area where waves break, carrying sediment up onto the beach and dragging it back into the water). The coarsest grains generally have undergone more rounding than finer grains. The majority of grains have a laminated structure visible under magnification.

The shrapnel grains have a dull metallic luster, except where red and orange rust survives on parts of grains protected from abrasion. They display various degrees of roughness, due to microporous surfaces produced during iron production and post- explosion corrosion. Corrosion products such as hematite, other iron oxides and biofilm made by iron-oxidizing microbes coat almost all surfaces, even those not visibly covered by rust.

In addition to the shrapnel, we also recovered 13 intact spherical iron beads, five hollow broken ones and 12 glass beads. The iron beads range in size from 0.1 to 0.3 millimeters in diameter. Most of them display a shiny luster on their outer surfaces and are nearly free of corrosion products.

Exactly how long the shrapnel and glass and iron beads will remain mixed in the sand at Omaha Beach is uncertain…..
Earle F. McBride and M. Dane Picard

The glass beads are remarkably uniform in size, between 0.5 to 0.6 millimeters in diameter, and are almost all spherical. The surfaces of beads are mostly smooth, with a few scattered divots, rare scratches and conchoidal spall pits. The beads are composed of clear glass, but they have various degrees of cloudiness, depending on the abundance of bubble inclusions.

Interestingly, the glass is not a pure silica glass, like one might expect to see. Energy dispersive spectrometer data show the presence of small amounts of calcium, sodium and magnesium, in addition to silicon and oxygen. We soon figured out the source of the unusual glass components and the other strange bits in our sand sample.

HOW THE GRAINS GOT THERE
It’s probably not surprising that we found shrapnel and glass and iron beads in the sand at Omaha Beach. The hardness of shrapnel ensured its survival in the sand. But what’s interesting is that the disparity in degree of rounding of shrapnel grains of the same size shows that, although originating on the same day and barring no major differences in hardness, the grains have not all had the same abrasion history and have not undergone continuous abrasion on the beach. It appears that some grains spent variable amounts of time in residence on the storm beach, the coastal berm, or an inner- shelf setting.

We think the glass and iron beads that we found were formed by munitions explosions glass beads from explosions in the sand and metal beads from explosions in both the air and in the sand. Such explosions would have been hot enough, at least 1200 degrees Celsius, to melt iron and heat quartz. Michael Martinez, supervising forensic scientist for Bexar County, Texas, says bomb explosions commonly produce hollow metal beads: Heat melts the iron, causing it to rain down in little pieces.

The explosions on their own probably wouldn’t have been enough to melt the quartz and form glass, but sodium and calcium present in seawater would have lowered the quartz’s melting temperature, allowing it to melt along with the iron upon explosion. It is likely that the scratches on the exterior of the glass beads formed while the beads were soft and undergoing turbulent rotation and impact with other particles just milliseconds after the explosion that generated them. Divots and chips formed from impacts with other particles after the glass had solidified, although whether this occurred in the air following the explosion (most likely), or on the beach, is uncertain.

THE LASTING TRUTHS
Not all of the sands from the D-Day beaches resemble the sand at Omaha Beach. Sands from Utah Beach, where the combat was less fierce, had no shrapnel in the sample we collected. We haven’t checked the other landing sites.

It is of course not surprising that shrapnel was added to the Omaha Beach sand at the time of the battle, but it is surprising that it survived 40-plus years and is doubtless still there today.

Exactly how long the shrapnel and glass and iron beads will remain mixed in the sand at Omaha Beach is uncertain. Iron on its own can probably survive beach abrasion for hundreds of thousands of years. But the combination of chemical corrosion and abrasion will likely destroy the grains in a century or so, leaving only the memorials and people’s memories to recall the extent of devastation suffered by those directly engaged in World War II.

About the Authors:
McBride is a professor emeritus at the University of Texas at Austin. Picard is a professor emeritus at the University of Utah in Salt Lake City. Both are sedimentary petrologists students of sedimentary rocks, the most common rocks on Earth’s surface.

Decades of collecting sand


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© D-Day’s Legacy Sands by Earle F. McBride and M. Dane Picard, published in EARTH Vol. 56 (No. 6), p. 38, June 2011.

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In The News

Tiny remnants of war found in Omaha Beach sand, Reuters, June 5th, 2012

Quand le sable raconte le Débarquement, Le Figaro, June 6th, 2012

Motu One, Tubuai, French Polynesia; By Andrew Cooper

By Andrew Cooper, University of Ulster

Tubuai is a small island in the Austral Island Group of French Polynesia, about 600km south of Tahiti.
The volcanic island is surrounded by a lagoon and a nearly continuous reef. On the reef flat there are several small islands of sand and coral rubble, known as motus.

Most motus are quite well vegetated, but one small example at Tubuai is completely bare and composed of a white coral sand beach. Called Motu One (pronounced O-nay), it is barely 250m long and 50m wide and is located on the reef crest on the north side of Tubuai.

The fact that such a small and isolated pile of sand survives even hurricanes is a perfect illustration of the ability of natural beaches to adapt to changing conditions….
—Andrew Cooper

On its seaward edge, Motu One has a ridge of beachrock which encloses a small lagoon. There are also a few small patches of beachrock on the lagoon side of the motu. The motu is affected by ocean waves on the north side and lagoon waves on the south and so water flows into the enclosed lagoon from both sides.

The seaward-facing beach is very steep but it is sheltered from the direct effect of ocean waves by the reef platform that absorbs a lot of the incoming wave energy. On the lagoon side, waves are less energetic but they are still able to carry sand and shells onto the beach surface.

The motu has changed shape several times but is anchored by the beachrock that helps keep it in place.

Motu One survived Hurricane Oli in 2011, which caused much damage on adjacent Motus and beaches on mainland Tubuai. The fact that such a small and isolated pile of sand survives even hurricanes is a perfect illustration of the ability of natural beaches to adapt to changing conditions.

The accompanying photos (supra) show the motu sitting on the reef crest, the beachrock ridge on its seaward side and the small lagoon that it encloses. The steep slope on the seaward-facing beach contrasts with the more gentle slope of the beach on the island side.

Playa Mar Chiquita, Puerto Rico; Pablo A. Llerandi-Román

By Pablo A. Llerandi-Román, Grand Valley State University

Playa Mar Chiquita, or the beach of the small sea, is located near the eastern end of the long ridge of eolianite exposed on the coast of Manatí in northern Puerto Rico, about 40 kilometers (25 miles) west of San Juan. Eolianite is a fossil wind-blown deposit that turned into a sedimentary rock. In this case, the ridge is an old line of sand dunes that formed at the back of an earlier beach when sea level was lower during the Ice Age. Water seeping down through the carbonate sand of the dunes deposited a natural cement of calcium carbonate, turning the dunes into rock.

Playa Mar Chiquita formed after wave erosion opened a gap in the eolianite ridge and water entered the basin forming a small lunate embayment. Today, the gap measures about 24 meters (80 feet) wide.

C. A. Kaye described the embayment “a small lunate resonating basin” in his classical work Shoreline features and Quaternary shoreline changes Puerto Rico (1959). Kaye suggested that the basin was almost completely excavated by resonating waves entering the embayment. He also observed that the waves inside the basin are of considerable height. Any visitor trying to swim in the basin today will observe the same phenomenon! Kaye interpreted the large size of the waves as the result of the backwash meeting the incoming waves at their breaking point, building up the size of the waves.

Playa Mar Chiquita formed after wave erosion opened a gap in the eolianite ridge and water entered the basin forming a small lunate embayment… The waves inside the basin are of considerable height…
—Pablo A. Llerandi-Román

Playa Mar Chiquita was once a popular secluded beach with a beautiful setting of palm trees, golden sand, and the imposing ridge of pitted eolianite that serves as a contrasting background for the blue clear sky, blue water, and sand. Today, Playa Mar Chiquita is still a gorgeous beach, but it is no longer as secluded as it once was due to the major urban development occurring on the coastal plains of Puerto Rico. However, the beach’s popularity has not declined. On any given day of the week you can see a few family picnics, visitors playing beach sports, or simply enjoying the landscape and sunbathing. One popular activity is to climb and explore the eolianite ridge that forms the rocky headland of Punta Mar Chiquita, on the northeast side of the beach. Hikers can see coastal processes in action as they experience the wave energy coming from the mighty Atlantic Ocean being expended on the rocks, and spraying the ridge, causing erosion and karstification that form interesting rock shapes due to the dissolution of the eolianite.

The eolianite of Playa Mar Chiquita is intensely pitted, with spikes and narrow sharp edges dividing the pits and pools. Cross-bedding in the calcareous sandstone forming the eolianite is easily observed on the edges of the ridge. Tidal terraces are a common feature on the ocean side of the ridge. Occasionally, water from the small basin, and water sprayed over the eolianite, reaches the back edge of the eolianite ridge, forming shallow, warm pools of calm seawater that are perfect for kids and adults looking for a relaxing environment away from the high waves of the embayment.

Playa Mar Chiquita also offers a few food kiosks and carritos operated by local neighbors that sell beverages, pinchos and frituras for the delight of visitors. Trees and uvas playeras provide much needed shade and the limestone geologic formations to the south expose the typical geomorphology of the Northern Karst Belt. The beach is off route PR-648 between the Reserva Natural Hacienda La Esperanza and Laguna Tortuguero.

Isles Bay Beach, Montserrat; Katie Peek & Robert Young

By Katie Peek and Rob Young, Program for the Study of Developed Shorelines / Western Carolina University

Isles Bay Beach is a small, embayed beach located on the western side of the Caribbean Island of Montserrat. This mountainous island is a British oversees territory, less than 20 square miles in area and dominated primarily by the Soufriere Hill Volcano. In 1995, the volcano began to erupt for the first time in recorded history, spewing ash and deadly pyroclastic flows directly on the capital of Plymouth, south of Isles Bay. Because the volcano continues to be active, the southern part of the island surrounding the volcano has been deemed an “exclusion zone” (See Map). These eruptions have forced over half of the population to relocate to other countries, primarily the United Kingdom.

Isles Bay Beach is located at the mouth of the Belham River, which runs west down from Soufriere Hills Volcano. Although the river is often no more than a trickle, the valley has been the recipient of significant volcanic debris flows since the eruptions began. In fact, the valley has more than doubled in width since 1995, with sediment flows covering many properties, including the island’s golf course.

As a result of the continued eruptions, the island has a large resource of volcanic sand located inland of the coast. The mining and exportation of this sand has steadily increased over the past 15 years. Originally, the sand mining was predominantly along the eastern, less populated side of the island, near the town of Trants. An eruption in 2010 covered this region with fresh pyroclastic material, destroying equipment and roads, and forcing the sand mining companies to look for another location. Recently, the sand mining has moved to the Belham Valley on the western side of the island.

… the current plan to export sand through the construction of new infrastructure along one of the most pristine, undeveloped beaches in the Caribbean, is not the answer…
—Katie Peek and Rob Young

The sand mined in Belham Valley is transported over 10 miles north to Little Bay, the location of the only viable pier (jetty) outside of the exclusion zone. The transport of this material by truck through Montserrat has caused much concern within the community, due to the noise, pollution, and the wear and tear on small residential roads. Therefore, the government is entertaining the option of building a new pier (jetty) for shipping the mined sand much closer to the source on the south end of Isles Bay Beach, just down Belham Valley.

This proposal has been criticized by property owners on the flanks of the Belham Valley, in the communities of Old Towne and Isles Bay Hill. Although a pier on Isles Bay Beach would eliminate the need to truck the sand across Montserrat, there is concern about the impacts the pier could have on the beach and coastal zone of Isles Bay.

The beach is currently used by fisherman, used as a recreational resource for the people of Montserrat, as well as a nesting beach for hawksbill turtles. Construction of this pier and an access road along the beach could potentially cause harm to the natural environment.

A recent Environmental Impact Assessment (EIA) of the mining activities was completed at the request of the Government of Montserrat. The EIA raises significant concerns about the impact that vehicular traffic will have on turtle nesting along the beach. This alone would kill the project in most places. Unfortunately, the EIA does not address the potential impacts that the new pier (jetty) will have on coastal process or nearshore habitat. The beach protects significant wetland ecosystems just landward of the sandy berm.

We have always advocated for the use of inland sources of sand in the Caribbean, and the Island of Montserrat has good sand. We hope that all parties can work together to find an organized approach to exploiting the resource that is sustainable, environmentally friendly, and economically rewarding.

We fear that the current plan to export the sand through the construction of new infrastructure along one of the most pristine, undeveloped beaches in the Caribbean is not the answer.

Morris Island Lighthouse & the Moving Beach; By Celie Dailey

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Morris Island Lighthouse, SC. Batik on silk, by © Mary Edna Fraser.
44” x 36”

By Celie Dailey

Morris Island Lighthouse is now located over 1,500 feet out to sea on a sand shoal surrounded by a small seawall. The relatively deep 35-foot foundation of the spindle has allowed it to continue standing as the land moved out from under it. Originally constructed a quarter-mile behind the beach, the lighthouse has survived storms, rising sea level, and barrier island migration since 1876.

In 1962, the light was extinguished. Managed by the US Coast Guard, it was let to stand as long as it was in good shape, but by 1965 there were plans to demolish it. The public alongside the Preservation Society of Charleston petitioned to let it stand, and so it was roped off as a dangerous structure, although no one took control of its maintenance. It was not until 1996 that citizens’ group Save the Light formed, acquired the structure for $75,00 and commenced its stabilization.

Seeing the lighthouse out in the sea is a clear reminder that our beaches and barrier islands are dynamic. It is thought that barrier island migration is related to sea level rise, but in this case the huge shoreline retreat is almost certainly due to sand loss caused by the jetties. The sand that has widened the south end of Isle of Palms just north of the jetties is the sand that would have flowed to Morris Island.

The huge ebb tidal delta, on the seaward side of the Charleston Harbor inlet believed to have been more than a billion cubic yards, began to break up after jetties were built in 1889. The breakup occurred because tidal currents and waves that combined to form the tidal delta over thousands of years were suddenly changed. Intended to deepen shipping lanes into the Charleston harbor, which were only about 12 feet deep at the time, the jetties were eventually extended to a length of 3 miles.

Seeing the lighthouse out in the sea is a clear reminder that our beaches and barrier islands are dynamic.
—Celie Dailey

Ebb tidal deltas can contain more sediment than the adjacent barrier islands and are the reason why navigation into harbors can be dangerous. As the tidal delta at the entrance to Charleston Harbor broke up, islands to the north and south were furnished with sand, causing Morris island to build out. (The landform now called Morris Island was three distinct islands in the 1700s). However, this source of sand did not last long and in the 1930s, after more than three decades of Morris Island building up, it suddenly started to erode. By 1938, the ocean shoreline had reached the lighthouse. A shallow shoreface allowed for the rapid migration of Morris Island across a hard layer of rock.

The Morris Island lighthouse can be seen as a tiny structure in the yellowed waters lit by the sun in Mary Edna’s batik image. In the foreground is Second Sister Creek, forming the estuary and inlet between Morris and Folly Island. Artist and photographer Mary Edna has been flying this landscape close to her home as long as she has lived in Charleston so her visual memory is loaded with renditions of this scene. For this batik, she combined an inspiring evening shot of a nearby scene with a mid-day shot of the actual geography of this area for her depiction.

Along the east coast, many lighthouses are threatened by their dynamic environments. The necessary proximity to the coast makes them vulnerable to sea level rise and erosion. Nationally there is a push to save these historic structures for their cultural, educational, and recreational uses. Many, like the Morris Island Lighthouse, have been validated as an object of preservation by being placed on the National Register of Historic Places.

Cape Hatteras Lighthouse (Outer Banks, NC) is seated on the highly erosive Outer Banks and was moved about 2,000 feet away from the its location in 1999 to prevent its demise. This relocation was controversial because local citizenry wanted the lighthouse to remain in its historic location. Although there was opposition, the year that the lighthouse was moved showed a spike in the number of tourist to the park (based on the National Park Service Statics Office report) and the lighthouse continues to be a major attraction. The National Park Service provided $9.8 million for its relocation, with a total cost of $12 million for the total relocation and restoration project.

Other lighthouses that have been moved include Block Island’s Southeast Light (Rhode Island) in 1993 and the Cape Cod Light (Massachusetts) in 1996. The Block Island Southeast Lighthouse Foundation is said to have raised $2 million in funds to pay for the relocation of the light 300 feet inland away from the eroding cliff of Mohegan Bluffs. The Cape Cod Light was moved 453 feet at a cost of $1.54 million when it was 100 feet from cliff’s edge. To date the tactics used to keep the Morris Island Lighthouse from succumbing to the sea have cost $5 million for a reconstruction of its foundation. $3 million was spent to build a steel cofferdam around the base of the lighthouse and $2 million was spent to replace the foundation with cement pilings.

Letting lighthouses succumb to the sea might be a reasonable thing to do in the face of rising ocean waters. It would show that we don’t have total control over nature and that sometimes human engineering fails. On a dynamic shoreline, there is no guarantee that lighthouses can be saved long-term when they remain in close proximity to the ocean. Allowing Morris Island Lighthouse to stay in its current location and strengthening its foundation might accommodate a rising sea, but direct impact from a hurricane will always be a danger along the Eastern seaboard.

Orrin H. Pilkey, co-author of Global Climate Change: A Primer (Duke University Press, 2011), served as editor of this article. Much of the material was drawn from his knowledge and published books. Orrin was a public advocate for moving the Cape Hatteras Lighthouse to its current location. Mary Edna Fraser illustrated regions around the world for “Global Climate Change: A Primer” with her batiks on silk.

Jurmala Beach, Latvia; By Andrew Cooper

By Andrew Cooper, University of Ulster

Situated on the Baltic Sea coast of Latvia, Jurmala Beach runs unbroken for over 30km along the Gulf of Riga. It forms a coastal barrier behind which the Lielupe River flows into the sea. The beach is about 100m wide, with about 50m being dry sand and 50m intertidal wet sand. There are well developed offshore bars along the whole length of the beach.

On the dry beach, small clumps of dune grass form embryo dunes, but the beach is backed by a distinctive 10m-high sand dune covered with a forest of small trees. This gives way landward to a flat coastal plain that is also forested. The beach is frozen and snow-covered in winter but in summer is a popular bathing area.

In addition to its beautiful sand beaches Jurmala has natural springs and mud from the adjacent river apparently has beneficial properties. The area was thus recognised as a popular spa resort since at least the 18th Century. It is easily reached from Riga by train. In addition to Latvian visitors, it is the closest beach for a large part of southwest Russia and Belarus. Russian soldiers recuperated there during the Napoleonic Wars and Tsars and Kings holidayed there as did Soviet Dictators.

The spectacular beach is well known for its powdery golden sands and a variety of curious ripples and bars are formed by the Baltic waves.
—Andrew Cooper

Since Latvia regained its independence in 1991 and joined the European Union, the resort has continued to be popular with Latvians and foreign visitors.

The spectacular beach is well known for its powdery golden sands and a variety of curious ripples and bars are formed by the Baltic waves. In addition, there are abundant trails of many creatures that live in the beach. Part of the beach has a Blue Flag award, identifying clean water and beach facilities and it is crowded with holidaymakers in the summer. Even in winter, however, dozens of beach walkers can be seen with thick coast and hats.

There are many hotels and dachas (holiday houses) of various styles and ages. Houses range from wooden shacks to small palaces, while several hotels originated and continue to exist as spas. Fortunately most of this development has taken place behind the coastal dune, so that the beach has not been blighted with sea defences. The dune forest extends right to the beach creating a wonderful natural vista along much of the beach.

Seawalls have been built in front of the few hotels that are built on the dune, but most of the beach infrastructure (pathways, shops, restaurants) is assembled in the summer and dismantled in the winter which avoids the need for defences.

It is to be hoped that as the resort continues to develop, these sustainable approaches to managing a beach resort will be continued and the temptation and pressure for development on the frontal dune can be resisted.