Category Archives: Beach of the Month

A Tsunami Sculpted Beach, Sermermiut Beach, Jacobshaven Icefjord World Heritage Site, South of Ilulissat, Western Greenland; By Harold R. Wanless And John C. Van Leer

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By Harold R. Wanless, Professor and Chair, Department of Geological Sciences, College of Arts and Sciences, University of Miami and by John C. Van Leer, Associate Professor, Division of Meteorology and Physical, Oceanography, Rosenstiel School of Marine and Atmospheric Science, University of Miami;

A most remarkable pair of small pocket beaches are nestled among the granitic cliffs at the mouth of Jacobshaven Icefjord. This Icefjord is about a third of the way up the western coast of Greenland, 250 kilometers north of the Arctic Circle. Sermermiut Beach is near the end of the – km board walk south of the fabulous, growing tourism town of Ilulissat. This boardwalk takes you out to overlook the mouth of a major Icefjord that drains ice from 1/7 of the Greenland Ice Sheet.

“Sermermiut, in Greenlandic “the place of the glacier people,” includes evidence of all three major Inuit periods of migration and settlement.”
— Harold R. Wanless & John C. Van Leer

The Icefjord is over 1000 meters in depth, about 5-7 kilometers in width, extends about 60 kilometers inland to the edge of the Ice Sheet, and then continues in deep channels far inwards under the Ice Sheet.
Eight thousand years ago a glacial tongue of the Ice Sheet extended all the way out of this Icefjord and deposited a terminal moraine of gravel at the mouth of the fjord. This gravel ridge is now about a marine sill 200-250 meters deep and arcs across the mouth of the Icefjord just off of Sermermiut Beach. Further into the Icefjord, fjord water depths increase from 1,000 to 1,500 meters in depth. The calving front of the ice has now retreated some 65 kilometers inward beyond the Ice fjord, into and under the Ice Sheet.

The forward speed of the Ice Sheet ice moving to the calving front has accelerated 6 fold (to some 30 km/year) in the past decade and the frequency of calving at the front has increased from a few times a week to several times a day. Locals say that the number of huge icebergs has diminished because of more intense fracturing associated with this acceleration, but the number of 100-150 meter high icebergs temporarily stranded on the gravel moraine adjacent to Sermermiut Beach is still very impressive and their splitting, rolling and collapsing is a frequent source of tsunami energy to the beach.

The beach is called Sermermiut. It is the prehistoric habitation site there (studied but invisible). It is a spectacular beach of gravel and sand studded with small to large chunks of ice (bergy bits) stranded there by tsunamis created by the frequent breaking and rolling of nearby giant icebergs temporarily stranded on the 250 meter deep moraine at the mouth of the Icefjord.

The Ancient Inuit settlement of Sermermiut dates from about 2,500 BC and is a major element of this diverse World Heritage site, the adjacent Jacobshaven Icefjord is the most productive in Greenland. Sermermiut in Greenlandic means “the place of the glacier people.” It includes evidence of all three major Inuit periods of migration and settlement. Archeological evidence of the following cultures were found: 1) Saqqaq culture 2500-100 B.C.; 2) Dorset culture 500B.C. – 200 A.C.; and 3) Thule culture 1000 – 1850 A.C.

“ … people are warned against venturing down onto the beach because of these frequent and rapidly arriving tsunami surges which range up to about 10 meters.”
— Harold R. Wanless & John C. Van Leer

This “beach of the month” has open water offshore in summer, maintained by fjord’s circulation with outward flowing (about 1.5 kilometer / per hour velocity) melt water at the surface. Winter pack ice formed a convenient base for seal hunting and ice fishing for Greenlandic Halibut. So, this protected area along the northwest edge of an exceptional biologically productive fjord has been prime real estate throughout the millennia and supported the largest town in Greenland of about 20 dwellings in 1737, according to the first Danish missionary Poul Egede.

A number of rectangular depressions mark sod dwelling sites which were used as winter quarters as recently as the early Danish colonial period according to Egede. The walls of these homes were similar to Norse construction, except there were alternate courses of sod and flat stone for added structural stability. During the summers, when the Inuit were exploiting remote food sources, the roof skins and poles were removed and used as portable tents, so the inside of the sod homes could air out.

Importantly, today people are warned against venturing down onto the beach because of these frequent and rapidly arriving tsunami surges which range up to about 10 meters. The close source of tsunamis would give very little warning time. While large calving bergs sometimes sound like very large artillery, rolling bergs make little or no sound. We watched a small tsunami from the breakup of a large iceberg far out in the Icefjord.

Some beaches are amazing just to appreciate from a distance.

Volunteer Beach, Falkland Islands; By Joe Kelley

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By Joe Kelley, University of Maine

The Falkland Islands are a place distant from most people, but magical in their wildness and wildlife.

It is not easy to drive to wild beaches (Figure 1), but drivers for hire abound and they ARE NECESSARY to drive across the open country. It takes about 2.5 hours to get from Stanley to Volunteer Beach.

Volunteer Beach is one of the nearest big beaches to the only town in the Falklands, Stanley. The beaches near Stanley are lovely and can be seen from a distance, but they were mined by the Argentines in the 1982 war and remain surrounded by barbed wire. Penguins may not set off the mines, but a person can!

In the first view one gets of Volunteer Beach (Figure 2), it looks like many other barriers around the world. It has a white sand beach that is backed by a low flat area and a lagoon. The water is a beautiful shade of blue that reminds one of the tropics. A small bathroom is located in the center of the flat ridge behind the beach.

A closer inspection (Figure 3) shows that the beach begins with a cobble patch with a blue-green sand dune plant colonizing the beach. No large dune exists landward of the beach however. The wind in the area is fierce, but there is no proper sand dune at all. The flat area behind the beach (Figure 3) is a sheep-grazed, penguin-burrowed area that is eroding more than accumulating sand.

The beach proper is made of almost pure quartz sand. This “sugar sand” beach is very rare. One might think of someplace as near to Antarctica as a formerly glaciated landscape, but not this part of the Falklands. The landscape is ancient and the rocks have been weathered down to almost pure quartz with few other minerals remaining.

“ The beach proper is made of almost pure quartz sand. This “sugar sand” beach is very rare.”
— Joe Kelley

The main attractions to Falkland beaches in November, when I visited, are the penguins (Figure 4). King Penguins, standing more than a meter high, are everywhere and not very shy. Visitors are asked to keep 6 m from them, but they often walk towards people. They stand and face the sea for long periods of time, and then suddenly rush forward and swim into the surf using their wings like paddles.
Among the small sand accumulations trapped by kelp in the back of the beach are several kinds of nesting birds (Kelp Goose, figure 5). It is best not to approach too closely when they are nesting or they might walk away from their chicks, a cold prospect for the small birds.

Penguins do not nest on the beach, and they “run” up the bluff bank after fishing to return to their colony. Gentoo Penguins (Figure 6) are a lot more fearful of people than King Penguins and move quickly across the beach. Some penguins have eggs and chicks in burrows on top of the ridge behind the beach. This landform is a peat deposit that the birds easily dig into (Figure 7). The Tussoc Grass that formed the peat was destroyed long ago by burning and sheep and no other native grasses replace it.

The backside of the peat deposit contains several large colonies of nesting penguins (Figure 8). These are somewhat roped off, but it is not difficult to photograph the King, Gentoo and Magellanic Penguins back here. One has to wonder at the impact of the penguins on the coastal landscape, as well as the profound impact of the sheep who walk among them. Prior to European colonization, the Falklands were uninhabited and Tussoc Grass grew all around the perimeter of the island. Now Tussoc Grass is seen only on inaccessible ledges (Figure 9). This grass, that formed the peat behind Volunteer Beach, grows to 3-4 m in height and would make the landscape very different in appearance if it were re-established.

Kamchia-Shkorpilovtsi Beach, Bulgaria; By Margarita Stancheva, Rob Young & Hristo Stanchev

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By Margarita Stancheva, Rob Young and Hristo Stanchev

In the middle of the Bulgarian Black Sea coast is Kamchia-Shkorpilovtsi beach, the longest sand beach in Bulgaria. The beach lies between two rocky headlands (Ilandgik and Cherni nos) and is located approximately 30 km away from Varna Bay (Fig. 1 and Fig. 2). Kamchia-Shkorpilovtsi beach begins 2 km north of the Kamchia River mouth and ends 2.5 km south of the mouth of Fandakliyska River. The name of the beach originates from its close proximity to the Kamchia River and Shkorpilovtsi village located further inland.

Kamchia-Shkorpliovtsi beach is a popular site for swimming, both for locals and for Bulgarian and foreign tourists. The beach is fairly undeveloped and natural, in particular in its southern part. The northern portion of the beach near the Kamchia River mouth has a few hotels for tourists and children’s groups from Russia who spend summer holidays in Bulgaria. Thanks to the lack of large hotels, the beach looks almost wild, even in the summer, and it is a preferred area for people who are seeking natural beauty and relaxation. The coastline here is straight and has an eastern exposure and the dominant winds blow from NE, E and SE directions.
The strong waves approach the shore mostly from NE and E, which makes the beach area one of the best on the Black Sea to practice surfing, windsurfing and kite surfing.

The research base of the Institute of Oceanology (IO-BAS) is located on the beach near the mouth of the Fandaklyiska River and includes a research station and a pier. There is work and living space for 35 people. The pier itself is 230 m long and 7 m high, and is used for mounting research gauge and other measurement equipment.

Kamchia River Basin


The Kamchia River is the longest river in Bulgaria and on the Balkan Peninsula to flow directly into the Black Sea, with a length of 244.5 km, has a catchment basin of 5357.6 km2 and an average water amount of 19.25 m3/s. The Kamchia starts at the confluence of two rivers springing from Eastern Stara Planina (Golyama Kamchia and Luda Kamchia), flows eastward to the Black Sea and empties into it 25 km south of Varna (Fig. 3).

“ The Kamchia River basin contains the best preserved flooded forests along the Bulgarian Black Sea coast.”
— Margarita Stancheva, Rob Young & Hristo Stanchev

The Kamchia River basin contains the best preserved flooded forests along the Bulgarian Black Sea coast. These low-lying forests, called “Longoz,” are a unique example of this type of habitat across Europe. Because of the need for environmental protection, this area was declared a natural reserve in 1951 by the Ministry of Forests and in 1977 it was included in the global network of biosphere reserves as part of the UNESCO “Human and Biosphere” Program. This network of reserves includes the protection of the most representative ecological systems on the planet. The forest is typically flooded by the Kamchia River, related to seasonal water level changes, which has led to strong vegetative growth that in places is almost impenetrable.

After its expansion in 1980, the reserve covers 842.1 hectares (ha) of wet forests by the mouth of the river. The lowest lying sections of the “Longoz” forests resemble a jungle, with creepers interweaving with trees or hanging down like thick draperies. Twenty-three fish species and numerous mammal species are found in the waters of the river and the adjoining marshlands. One of the most interesting features of these forests is the feathered inhabitants. Kamchia is situated on the migratory flyway “Via Pontica,” which allows for the observation of various bird species that stop to rest and feed during migration. Many interesting and rare birds breed in the area, such as Black Stork, Lesser Spotted Eagle, Great Spotted and Lesser Spotted Woodpeckers, Tawny Pipit, Barred Warbler, Semi-collared Flycatcher and Icterine Warbler. Visitors traveling through Kamchia reserve must follow marked paths and specified rules.

Geomorphology


Kamchia-Shkorpilovtsi beach is 12.4 km long, with an area of 500 294 m2 and about 25 m average width. In the northern section, where the beach and sand dunes are leveled by bulldozing, it is up to 110 m wide (Fig. 4). The adjacent coast is built by limestones, Paleogene sandstones, marls and clays, and in Eastern Stara Planina by Upper Cretaceous sandstones, aleurolites, argillaceous rocks and limestones. The average rate of erosion of these rocks is 0.16 m/y.

The beach is composed of fine to medium quartz sands with low carbonate content (3-8 %), which originate from the erosion of the sandstone rocks outcropping at the coast. These sandstones consist of 80% quartz grains cemented with lime substance brought from the Kamchia and Fandakliyska rivers.

There are well-developed foredunes on the back side of the beach. Landward of these foredunes are vast fields of stabilized and vegetated dunes, followed by forested dunes located further inland. Dune systems occur behind the beach, where their development has been favoured by the dominant wind direction and ready supply of sediment (Fig. 5).

Near the mouth of the Kamchia River, there is a large dune bar parallel to the coastline, which has a maximum height of 6 m. Since the coast here is exposed to NE, E and SE winds, a number of dunes with heights up to 8 m are formed landward just behind the bar. Similar climate conditions (dominant winds from E, NE and SE directions) have also shaped a comparable dune landscape around the southern part of the beach, distinguished by large foredunes and parallel dunes located inland (Fig. 6).

Just offshore, the coastal slope is shallow and primarily comprised of sands and aleurolites (silt sediments). The northern section is commonly 500-600 m wide and the widest section is 1 km near the mouth of the Kamchia River. The boundary between sands and aleurolites is at a depth of approximately 20-25 m, but near the river mouth this boundary can be found at shallower depths (around 8-12 m). This is a result of the large amount of alluvial material being deposited by the river.

A rocky platform at a depth of 6 m and 30-40 meters wide stretches intermittently along much of the shoreline near the mouths of the Kamchia and Fandakliyska rivers. This platform consists of lime sandstones and has an asymmetrical shape, with the highest part next to the shore. This rocky platform is a natural defense of the existing beach from direct wave impact.

Beach morphodynamics


As the beach is still undeveloped and has no coastal protection structures, its dynamics remains natural and fairly stable. Winter storms commonly cause erosion, as strong waves reshape the beach profile and reach the backshore, thus causing erosion of the foredunes as well. However, in the summer the beach returns to its stable condition. Sands are transported alongshore from north to south, as it is the general sand transport direction for the entire Bulgarian coast. Although the beach is generally stable, strong storm waves can flood the beach and provoke erosion of the foredunes and even of relict dunes located at some distance landward (Fig. 7).

Until the early 1990s Kamchia-Shkorpilovtsi beach was characterised mostly by accumulation; previous research by Dachev et al. (2005) found that between 1958 and 1991 the shoreline migrated seaward 12.7 m. The situation has changed over the years as a result of human impacts on the Kamchia River, primarily hydraulic construction such as artificial lakes, long impermeable river corrections and engineered defense structures. The natural river flow and sediment load has been disturbed causing a sediment deficit along the shoreline. In addition, the decrease in discharge of solids has been exacerbated by the extraction of sands and shingle material from the river bed. In the entire catchment basin of the Kamchia River, 82 artificial lakes were built. After construction of three artificial lakes during 1972-73, the discharge of sediments of the Kamchia River decreased from 2 000 000 t/y to 500 000 t/y. As a consequence, the sediment balance in the Kamchia River area has been disturbed and this has adversely impacted Kamchia-Shkorpilovtsi beach by reducing beach area and width. The most recent observations (2013) for the period 1983-2011 indicate that although erosion rates are low, the shoreline has retreated 2.30 m or 0.08 m/y (Fig. 8).

Sand dunes


Sand dunes are active on the backshore of the beach and become more stabilized and fixed landward as they are covered with vegetation and forests. Located between the mouths of the Kamchia and Fandakliyska rivers, is the largest dune complex on the Bulgarian coast. This dune complex is made up of shifting, stable vegetated and rare grey dunes (grey stabilised dunes with wet dune slacks and forested dunes, Fig. 9) and is 7180 m long with an area of almost 2 km2. The complex is a priority conservation habitat in the European Union. The beach and foredunes (mobile) are characterized with typical psammophyte vegetation (Fig. 10).

“ As the beach is still undeveloped and has no coastal protection structures, its dynamics remains natural and fairly stable.”
— Margarita Stancheva, Rob Young & Hristo Stanchev

Even though the beach and dunes still remain less urbanized and are subject to legal protection, they have been exposed to some human-induced threats, such as litter from tourists. Additional litter and industrial pollutants regularly wash up on the shore, much of which comes from either the port of Varna or ships traveling just offshore.

Other threats to this coastal area include: 1) unregulated camping and “temporary” construction on the beach and dunes, 2) a lax regulatory environment that tolerates the re-zoning of protected sand dunes to “agricultural” areas (thereby allowing for easier transition for development), 3) sand compaction and destruction of rare dune habitats during the summer when large numbers of tourists cross the dunes to reach the beach, 4) off-road driving and parking, 5) illegal sand extraction, 6) afforestation with non-native species, such as Pinus Maritima which was introduced in the 1970s leading to the degradation of dune habitats here (Fig. 11).

The most impacted section of Kamchia-Shkorpilovtsi beach is to the north near the Kamchia River mouth. Along this developed portion of the shoreline, the beach and dunes have destroyed by bulldozing and leveling. Although the beach is not overdeveloped, it has been the most impacted over the past decades and it is unknown whether these dunes will naturally recover.
The expansive dune fields and beach are collectively referred to as “Kamchia sands.” In 2006, an investor succeeded in removing the protection status of these beach and dune areas. Due to its high conservational value, the protected area is also subject to the Environmental Network NATURA 2000 of the European Union, Ramsar Convention on wetlands, Council Directive 92/43 and other conventions. Therefore, one of the major threats to Kamchia-Shkorpilovtsi beach is the elimination of the protected status of “Kamchia Sands.” There is also a threat of ending the conservation status of the area because of logging and construction of hotels and supporting infrastructure on the shoreline.

Conclusions


Kamchia-Shkorpilovtsi beach is the longest beach in Bulgaria and is distinguished by vast areas of preserved rare sand dunes which are a priority habitat in Europe. For many years prior to human construction on the Kamchia River, the beach remained stable and did not experience significant erosion. Although erosion rates are still relatively low, the shoreline has been retreating since the early 1990’s. We suggest that if the beach remains naturally functioning, its dynamics and morphology will not experience large changes in the near future. The only real threat to the beach is associated with coastal development plans to build new infrastructure that will increase tourism.


References:

  • 1. Council Directive 92/43/EEC of 21 May 1992 on the conservation of natural habitats and of wild fauna and flora. Official Journal of the European Union L 206, 22.7.1992, p. 7.
  • 2. Dachev, V.Z., Trifonova, E.V. and Stancheva, M. K. 2005. Monitoring of the Bulgarian Black Sea Beaches. (In), Guedes Soares, Garbatov & Fonseca (eds.) ‘Maritime Transportation and Exploitation of Ocean and Coastal Resources’Taylor & Francis Group/ Balkema, 1411 – 1416.
  • 3. NATURA Project stuff, 2000. Preparation of the Bulgarian Natura 2000 Network of Protected Zones.
  • 4. Peychev V. and Stancheva, M. 2009. Changes of Sediment Balance at the Bulgarian Black Sea Coastal Zone Influenced by Anthropogenic Impacts. Compt. Rend. Acad. Bulg. Sci, 62, 2, 277-285.
  • 5. Peychev V. 2004. Litho- and morphodynamic of the Bulgarian Black Sea coastal zone. Publ. House “Slavena”, Varna, 231 p. (In Bulgarian).
  • 6. Sixteen cases of Natura 2000 vandalism in Bulgaria. Retrieved in pdf from: BirdLife International
    (http://www.birdlife.org/eu/pdfs/Nature_Directives_material/Portfolio_texts%20_final.pdf ; last accessed on 23.01.2014).)
  • 7. Stancheva, M., 2010. Sand dunes along the Bulgarian Black Sea coast. Compt. Rend. Acad. Bulg. Sci., 63 (7), 1037-1048.
  • 8. Stancheva, M., Ratas U., Orviku K., Palazov A., Rivis R., Kont A., Peychev V., Tõnisson H. and Stanchev H., 2011. Sand dune destruction due to increased human impacts along the Bulgarian Black Sea and Estonian Baltic Sea coasts. Journal of Coastal Research, SI 64 (Proceedings of the 11th International Coastal Symposium), 324-328, Szczecin, Poland, ISSN 0749-0208.
  • 9. Tzonev, R. 2011. Red Book of Bulgaria, Volume 3, Natural habitats. Issued by Bulgarian Academy of Sciences and Ministry of Environment and Water of Bulgaria.
  • 10. Tzonev, R.; Dimitrov M. and Russakova, V., 2005. Dune vegetation of the Bulgarian Black sea coast. Journal Hacquetia, 4 (1), 7-32.
  • 11. Kamchia (biosphere reserve)
  • 12. Bulgaria Travel- Kamchia Reserve
  • 13. Kamchia Biosphere Reserve

Black Sea Coast of Bulgaria, Flyover: A Photo Gallery, By The Program for the Study of Developed Shorelines (PSDS)

The Program for the Study of Developed Shorelines (PSDS) collaborated with the Bulgarian Academy of Sciences Institute of Oceanology (IO-BAS) to conduct the first comprehensive photo survey of the Bulgarian Black Sea Coast. Images were acquired July 10 and 11, 2013.

The flight progressed from the Romanian border in the north to the Turkish border in the south with close to continuous coverage. The project was funded jointly by PSDS and IO-BAS along with support from the Bulgarian Fulbright Commission.

Sand Beaches Of The Northeast Coast Of Saudi Arabia; By Miles O. Hayes and Jacqueline Michel

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By Miles O. Hayes and Jacqueline Michel, Research Planning, Inc.

Introduction

The purpose of this discussion is to describe the geomorphology and dynamic coastal processes of the sand beaches along the northeast coast of Saudi Arabia. As shown on Figure 1 (See above gallery), the study area extends from the Kuwait border to the southern end of Abu Ali. This is, in effect, the shoreline oiled during the Gulf War oil spill of 1991, the largest oil spill in history (11 million barrels). In 2002 and 2003, twelve years after the original spill, our field team determined that eight million cubic meters of oiled sediment remained on the shoreline, mostly in oiled crab burrows in the sheltered marshes and tidal flats. There was still some oil on the sand beaches, as will be discussed below.

The work described in this paper was conducted during two main field projects. Starting in January of 1992, our team participated in a study to determine the immediate impacts of the Gulf War oil spill that was sponsored by the National Oceanic and Atmospheric Administration (NOAA). This work included participating in the cruise of the NOAA R/V the Mt. Mitchell. In addition, at that time, 17 permanent beach profile stations were established that were monitored up through 1997. John Robinson was the contract monitor for the Mt. Mitchell portion of the project. Also, the Marine Spill Response Corporation (MSRC), with Don Aurand as contract monitor, provided support for the beach monitoring work. In 2002-2003, we directed a six-month field project to determine the long-term impacts of the Gulf War oil spill in the study area (Figure 1) with funding from the United Nations Compensation Commission. During this project, 3,107 intertidal transects were surveyed. Throughout all this work, we were grateful for the guidance and support of the Presidency of Meteorology and Environment (PME) of the Kingdom of Saudi Arabia.

Physical Setting


General
The Arabian/Persian Gulf is shallow, with an average depth of 35 meters (m) and a maximum depth of around 100 m. Rainfall is meager (50 centimeters [cm]/year) and evaporation rates are high, resulting in salinities averaging up to 38-41 parts per thousand (ppt). The ocean waters that enter the Gulf through the Strait of Hormuz generally flow to the northwest, hugging the shoreline of Iran under the influence of the Coriolis Effect (i.e., deflected to the right in the northern hemisphere). Some fresh water enters the Gulf at its northern end at the Shatt Al Arab.

“ On the exposed outer sand beaches of the study area, sand-sized particles, composed predominantly of quartz, carbonate shells, and coral fragments, are the most common sediment type.”
— Miles O. Hayes & Jacqueline Michel

Water exiting the northern end and flowing south is also deflected to the right, such that the surface flow trends southeast along the Saudi Arabian Coast, continuing on into waters of the United Arab Emirates, where the long-term evaporation of these waters has created some of the highest salinities in the Gulf. Salinities up to 70 ppt sometimes are recorded in the Gulf of Salwa, 200 kilometers (km) southeast of the southern border of the study area (Meteorology Environmental Protection Agency (MEPA), 1987).

The climate of the study area is hot and dry. The air temperature averages 37°C in August and 12°C in January. Water temperatures range from 15 to 33°C, a large range that is a result of the shallow and almost landlocked character of the adjacent waters (MEPA, 1987).

It is important to note that this shoreline is subject to neither tropical nor extratropical cyclones, nor are major impacts of the monsoon of importance. This fact makes this area somewhat unique in comparison with other coasts around the world.

Because of its shallow nature, the Gulf has undergone some major changes during the ice ages (Pleistocene epoch), in that during each of the four major glaciations, the Gulf essentially went dry. During the last one, the Wisconsin Glaciation, which peaked about 20,000 years Before Present (BP), sea level dropped as much as 120 m. Sea level started to rise about 12,000 years BP, and reached its present level around 5,000 years BP (with regard to the ocean surface; not necessarily with respect to the adjoining land mass). Consequently, the landforms along the present Gulf shoreline are relatively young, in a geological sense.

Geology/Geomorphology
The Gulf area is a low-lying area adjacent and parallel to a mountain belt formed as a result of the collision of two tectonic plates, the Arabian and Eurasian Plates (Figure 2). The Arabian/Persian Gulf is the marine portion of an extensive peripheral foreland basin formed as the Arabian and Eurasian Plates collided during the Zagros Orogeny, which took place in Plio-Pleistocene time (23 to 2.6 million years BP) (Lees and Falcon, 1952; Dickinson, 1974; Jordan, 1981). Up to the present time, the rivers in the north have filled in about half of the former Gulf with sediment, meaning that, if this process continues, the Gulf as we now know it will be no more after around another 10 million years or so.

Tides
Tides and the associated tide-generated currents are the most important dynamic physical process affecting sediment distribution and transportation in the sheltered bays of the study area. The tides are surprisingly complex in the Gulf (Defense Mapping Agency USA, 1975). They are driven by two amphidromic systems, the margins of which meet in the study area. From one spring tide to the next, the tides commonly range from semidiurnal to highly mixed and, at times, approach a diurnal configuration. Thus, complicated patterns of high and low tides, as well as asymmetric current patterns, occur within the area discussed here (Figure 1; referred to as the study area in the following discussion). During our research on the Saudi Arabian Coast, that continues to this day, tide-level conditions drive the scheduling of all fieldwork, inasmuch as the daily field surveys are conducted under optimum low-tide conditions.

The mean tidal range decreases along the western coast of the Gulf from 3 m at Kuwait to 1 m at Ras Tanura, Saudi Arabia (Defense Mapping Agency USA, 1975). Although the tidal range of the study area typically averages around 1.5 m, the intertidal flats in the region are extensive, reaching over 2 kilometers (km) wide in places, a phenomenon found most commonly in macrotidal areas (tidal range greater than 4 m). The wide intertidal zone is a result of the relatively flat hinterland and the shallow character of the adjacent Gulf floor.

Tidal currents are strong in the major tidal channels of the study area, with maximum velocities of 0.5-0.8 m/second (s) occurring frequently. Current data recorded by current meters established in the study area by Hayes, Michel, and Montello (1993) showed that ebb currents typically are stronger than flood currents in Dawhat al Musallamiyah and vice versa in Dawhat ad Dafi, two bays in the southeast corner of the study area. This difference probably is a result of the contrast in the morphology of the two bays, but this phenomenon has not been investigated in detail.

Shamal Winds
The meteorological explanation of Shamals, which blow consistently out of the northwest (see wind roses for Mina al Ahmadi, Kuwait and Ras Tanura, Saudi Arabia in Figure 3) and may occur throughout the year, is beyond the scope of this discussion. However, they are particularly strong in the late spring when dust storms are common (Edgell, 2006). Also, a winter Shamal is associated with the strengthening of a high pressure over the Arabian Peninsula after the passage of a cold front while a deep trough of low pressure maintains itself over areas east of the Arabian/Persian Gulf (see general model in Figure 4). This leads to strong northwesterly winds over the Gulf for periods up to five days (El-Baz and Makharita, 1994).

Waves and Longshore Sediment Transport
There are limited data on the wave conditions along the coastline of the study area. Field studies in Kuwait by RPI (1977) documented maximum heights of breaking waves to be less than 1 m. Wave heights obviously increase to the south along the Saudi Arabian Coast as the fetch in a northwesterly direction increases. The island of Abu Ali has an open fetch of 250 km to the north. Breaker heights greater than 1 m should be common on the headlands in the study area.

“ …this shoreline is subject to neither tropical nor extratropical cyclones, nor are major impacts of the monsoon of importance. This fact makes this area somewhat unique in comparison with other coasts around the world…”
— Miles O. Hayes & Jacqueline Michel

However, breaking waves greater than about 60 cm in height rarely were observed during our field surveys in 2002-2003. During the late spring and summer months, when strong Shamal winds usually occur, the waves also tend to be consistently larger, although according to Reynolds (2002), “The winter Shamal occasionally sets in abruptly with great force and speed above 10m/s, and gale force Shamals occur once or twice each winter and bring the strongest winds and waves of the season.” Our detailed field surveys were carried out between late September 2002 and early March 2003.

There is significant geomorphic evidence to suggest a dominant northwest-to-southeast longshore sediment transport direction along the Saudi Arabian Coast. There are a number of major depositional headlands, some of which are cuspate spits that have associated sand spits that trail off to the southeast. The general model and a typical example of one of these cuspate spits is illustrated in Figure 5.

Also, as observed while reviewing the aerial videotape of the shoreline of the study area taken as part of our field survey during October 2002, a number of crenulate bays show a classic fish-hook shape with the hook shank extending to the east or southeast, indicating sediment transport in that direction. Numerous other features observed on the videotape, such as oblique nearshore bars, rhythmic topography, natural groins, and other sedimentation patterns (e.g., subtidal sand flats with abundant large sand waves that project to the east and southeast away from the onshore spits) also reflect the dominant southeasterly longshore sediment transport direction. The cuspate spit headlands near the Kuwaiti border are more symmetrical than the ones to the south and are separated by sandy arcuate embayments, which is a reflection of the more limited fetch from the north along the Kuwaiti shoreline. This change in the cuspate spit shapes and orientations is illustrated in Figure 3.

Beach Sediments
On the exposed outer sand beaches of the study area, sand-sized particles, composed predominantly of quartz, carbonate shells, and coral fragments, are the most common sediment type. All eight of the outer sand beaches studied during the Mt. Mitchell scientific expedition in early 1992 were composed of medium – (0.25-0.5 millimeters [mm]) to coarse-grained (0.5-1.0 mm) sand (Hayes, Michel, and Montello, 1993). The mean grain size of the sediments on exposed outer sand beaches is 0.7 mm, and these sediments have the highest degree of sorting of all habitats that were studied.

Beachrock, Sabkhas, and Algal Mats
Beachrock is sediment consolidated into solid rock recently (relative rapid process) by the precipitation of calcium carbonate from sea water into the pore spaces between sand grains, a process enhanced by warm water and high salinities. Beachrock is very abundant in the intertidal and shallow subtidal areas all along the western shoreline of the Gulf.

Coastal sabkhas are very flat, supratidal surfaces that typically border the high spring tide line, being flooded occasionally during exceptionally high spring tides and storm surges. They are typically composed of carbonate mud sediments and wind-blown silt and fine sand of variable composition. These sediments typically contain an abundance of evaporite crystals, such as halite and gypsum.

Algal mats are sheet-like accumulations of blue-green algae (Cyanobacteria) commonly developed in intertidal environments in the Gulf. The algae cover the sediment surface and will in turn trap sediment to produce a laminated alternation of dark, organic-rich algal layers and organic-poor sediment layers. They commonly form a band in the mid to upper intertidal zone around sheltered bays. They are an important food source for some organisms. Some examples of these rather diversely shaped mats are pictured in Figure 6.

Wave Exposure
The 3,107 intertidal transects surveyed during our 2002-2003 survey were sorted into categories based on exposure to wave action and coastal habitat type. Coastal biologists long have used the concept of exposure to differentiate among coastal habitats, a classic reference being Ricketts et al. (1985). Also, exposure is used as a means of delineating the sensitivity of coastal habitats to oil pollution, with the most exposed habitats being least sensitive and the most sheltered being most sensitive (Hayes, Gundlach, and Getter, 1980). Accordingly, the coastal habitats of the study area were so classified. In this discussion, we will focus on the exposed outer sand beaches, moderately exposed sand beaches, and sandy tidal flats.

Generally speaking, all of the stations classified as exposed have open fetch distances measured in tens of kilometers. Sediments on these transects are medium- to coarse-grained sand (or gravel in some areas) that is subject to considerable wave action. The moderately exposed stations typically have fetch distances confined within the bays and the sediments, while still either sand or muddy sand, tend to be finer-grained than those on the more exposed transects. Most of the transects we classified as sheltered have open fetches less than 2 km and the sediments are either pure mud or sandy mud.

During the fieldwork, it was clear that exposure of the habitat had played a major role in the retention of oil within the sediments along the transects. A search of the literature revealed that wave data needed to make a distinction among exposure levels of the individual transects were not available. Accordingly, an index of wind-wave exposure in the northwestern Arabian Gulf was derived by our team using a raster wind-wave model. The details of the model are given in RPI (2003).

Exposed Outer Sand Beaches


Description
The sand beaches that occur in the exposure zone referred to as exposed extend along 141 km of shoreline and occur on 564 of the 3,017 transects (19%) surveyed in the impacted area during our 2002-2003 surveys. They represent 22% of all sand beaches.

Although wave data for these areas are lacking, the beaches are clearly exposed to frequent episodes of intense wave action, judging from the relatively large size of the beach berms, the excellent sorting of the sediments, and the presence of erosional and depositional features on the beaches. Examples of aerial views of these beaches are given in Figure 7.

Morphology and Sediments
A beach develops where sediment particles are available and waves are large enough to mold the sediments into a depositional berm. The exposed, outer sand beaches of the study area typically are made up of three basic morphological components:

  • Berm top:
  • A landward-sloping (0-5 degrees), smooth surface that is washed over during high spring tides and during periods of heavy wave activity.

  • Beachface:
  • The seaward-sloping (3-12 degrees), smooth face of the berm that is subject to the uprush and backwash of the waves at mid- to high-tide levels.

  • Low-tide terrace:
  • A gently sloping (1-3 degrees) surface exposed at low tide that may contain complex sandbar systems. This surface merges almost imperceptibly into a wider sandy tidal flat in many locations.

These components of exposed sand beaches are illustrated by the generalized topographic cross-section given in Figure 8. Such beaches are characterized by episodes of both erosion and deposition.

” In places, the accretion rates were quite impressive… The potential for burial of oiled sediment layers as much as tens of centimeters is possible on such beaches.”
— Miles O. Hayes & Jacqueline Michel

During periods of high wave activity, sandy sediments deposited on the berm during periods of lesser waves are eroded off the berm and deposited on the offshore tidal flat or perhaps even into the subtidal area further offshore. The sand thus displaced offshore of the high-tide area is returned during calmer weather in the form of intertidal bars (see Figure 8). Thus, the potential for burial of oiled sediment layers as much as tens of centimeters is possible on such beaches.

On the exposed outer sand beaches of the study area, sand-sized particles, composed predominantly of quartz, carbonate shells, and coral fragments, are the most common sediment type. All eight of the outer sand beaches studied during the Mt. Mitchell scientific expedition in early 1992 were composed of medium- (0.25-0.5 mm) to coarse-grained (0.5-1.0 mm) sand (Hayes, Michel, and Montello, 1993). For that study, the mean grain size of the sediments on exposed outer sand beaches was 0.7 mm, and these sediments have the highest degree of sorting of all habitats that were studied.

Oil Distribution and Characteristics
A field sketch of an exposed outer beach located approximately 10 km north of Ras az Zawr is given in Figure 9, and its topographic profile and oiling conditions one year after the spill are given in Figure 10. Hayes, Michel, and Montello (1993) estimated that 60% of the oil deposited on the outer beaches north of Ras az Zawr (northwest half of the shoreline in study area) had been eroded away 1 year after the spill. However, at this particular station, two layers of buried oiled sediments from the 1991 oil spill were still present in March 1992, one year after the spill.

Although the oil distribution patterns on the outer sand beaches showed considerable variation along the shore, in our 2002-2003 surveys we noted that there were three basic patterns that dominated twelve years later:

  • (1) Much of the oil originally deposited on these beaches had been eroded away by wave action during the twelve years following the spill.
  • (2) In areas where the beaches were undergoing long-term accretion, the oiled sediments had been buried.
  • (3) Heavily oiled beachface sediments had been consolidated into asphalt pavements in a few places, some of which was still exposed on the surface of the beachface.

Of the 564 transects classified as exposed outer sand beaches, 280 (50%) contained no visible oil at the time of our survey in the fall and winter of 2002/2003. Based on a study of satellite imagery and shoreline surveys conducted by MEPA (1991), most of these beaches were oiled during the 1991 oil spill. Therefore, it is assumed that in the areas that contained no visibly oiled sediments, the oiled sediment has been removed by wave action, a process that was observed during the 1992 and 1993 Mt. Mitchell surveys (Hayes, Michel, and Montello, 1993; Michel et al., 1994).

Though depositional patterns on these beaches were not studied in detail during the 2002-2003 surveys, at least half of them appeared to be undergoing long-term accretion, which had led to burial along transects where the oiled sediment was not eroded away within a few years after the spill. As noted earlier, the accretion of the beach is accomplished by the welding of intertidal bars onto the beachface/berm areas in the upper intertidal zone. This process is aided by the progressive alongshore migration of massive wedges of sand called rhythmic topography, an example of which is pictured in Figure 11A. An aerial view of a small shoreline rhythm and a welding intertidal bar is shown in Figure 11B. In places, the accretion rates were quite impressive. For example, at Mt. Mitchell station GWS-8, the backbeach area was erosional in January 1993, as is shown by the beach sketch in Figure 12. However, ten years later in January 2003, this beach had accreted 30 m (Figure 13). This resulted in burial of oiled sediment, such as that illustrated in Figure 14.

Asphalt pavements of at least two distinct origins were encountered in the study area in 2002-2003. A very hard, solid black pavement of oil derived from the Nowruz spill of 1983 essentially blanketed the intertidal zone of the exposed outer beaches on Abu Ali Island (Hayes, Michel, and Montello, 1993). The pavements formed from the 1991 oil spill typically were softer than the Nowruz pavement, were lighter in color (medium brown), and contained a significant amount of sediment. Photographs of these two types of pavement are given in Figure 15. Most of the asphalt pavement located north of Ras az Zawr was visually determined to be pavement from the 1991 oil spill (see photograph in Figure 15B), and generally speaking, it did not have either the continuity or the consistency of the Nowruz pavement. The longest continuous band of 1991 oil spill pavement, approximately 5 km and averaging 10 cm thick, coated the entire intertidal zone of the beach just south of the Prince Sultan Beach Resort.

Moderately Exposed Sand Beaches


Description
The sand beaches that occur in the exposure zone referred to as moderately exposed extend along 406 km of shoreline and occurred on 1,625 of the 2002-2003 transects. They represent 78% of all sand beaches in the study area. Although, as noted earlier, wave data for these beaches are lacking, they are clearly exposed to less frequent episodes of intense wave action than the outer exposed sand beaches, judging from the relatively smaller size of the beach berms, and the absence of clear-cut erosional/depositional features on the beaches. Ground views of two of these beaches are shown in Figure 16.

Morphology and Sediments
These beaches have a morphology similar to the exposed outer sand beaches in that they contain a berm with associated berm top and beachface, and an adjacent tidal flat that may contain intertidal bars. However, the berms on these beaches, which are located on shorelines more sheltered than the outer beaches, are much smaller. Also, because of the smaller waves, changes in morphology are slower and more subtle. Usually the tidal flats adjacent to these beaches are very wide, because they typically are located in bays with shallow depths. A general model of this beach type is given in Figure 17.

Similar to the exposed outer sand beaches, sand-sized particles, composed predominantly of quartz, carbonate shells, and coral fragments, are the most common sediment type. Grain size of sand in the study area is complicated by the fact that a significant portion of it is blown from the desert onto the shore where it mixes with sediment derived from other sources, such as erosion of rocky headlands. Therefore, in this area the environmental setting itself is not as important in determining the grain size of the sediments as it is on most shorelines. Three of the four moderately exposed sand beaches studied during the Mt. Mitchell scientific expedition in early 1992 were composed of medium-grained (0.25-0.5 mm) sand (Hayes, Michel, and Montello, 1993). In the 2002-2003 study, the mean grain size of the sampled beaches was 0.7 mm, or medium-grained sand, the same as the exposed outer sand beaches. However, the sand on the moderately exposed sand beaches is less well sorted, with a sorting coefficient of almost 6, compared to 3.5 for the exposed sand beaches. The mean grain size of the sand on all sand beaches in this area is similar because the sand is derived from the same sources, and wind-blown sand is a major contributor. The moderately exposed sand beaches have poorer sorting because the finer-grained sediments are not as frequently winnowed out by large waves.

Oil Distribution and Characteristics
Along the 406 km of moderately exposed sand beaches, 166 km (41%) were free of visibly oiled sediments whereas 240 km (59%) contained oil at the time of our survey in 2002-2003. The volume of oiled sediments was estimated to be about 632,500 m3, representing about 8% of the total volume of oiled sediments in the study area. Because the degree of exposure is lower than on the outer beaches, infauna can be more common. As a result, oiled burrows represented nearly 16% of the oiled sediments (compared to 0.2% on exposed sand beaches). An example showing the preservation of oiled burrows is given in Figure 18. Also, it is apparent that on these moderately exposed sand beaches, the rates of natural removal and burial of the sediments oiled during the 1991 oil spill are relatively minimal.

Highly Exposed Sandy tidal Flats


Description
According to MEPA (1987), a total of 92% of the area of the intertidal zone (at low tide) of the east coast of Saudi Arabia is occupied by intertidal flats. The mapping results of our 2002-2003 study show that 87% of the intertidal zone of the study area consists of tidal flats, by far the most abundant habitat type, with the possible exception of the sabkhas, which have an essentially limitless landward extent; hence, their areal extent was not measured. Based on the transect data from our 2002-2003 surveys, exposed sandy tidal flats were present on 300 transects and thus 75 km of coastline.

” Liquid oil in burrows was found in a number of localities during the 2002-2003 surveys, twelve years after the spill…”
— Miles O. Hayes & Jacqueline Michel

Morphology and Sediments
The more highly exposed pure sand flats, such as the ones pictured in Figure 19, show evidence of relatively high wave and/or tidal current action. Their sediments are coarse-grained sand (mean = 0.68 mm), which is typically well sorted. Many of these flats contain mobile sand waves and megaripples (e.g., Figure 19A).

Oil Distribution and Characteristics
For the most part, these highly exposed flats did not typically contain an over abundance of oiled sediments during our 2002-2003 surveys, because of the high level of sediment motion under the influence of waves and tidal currents, as well as the thin nature of the sediments over the underlying beachrock terrace. Of the 300 transects that included exposed sandy tidal flats, oil remained on 136 transects (45%). Reported another way, of the 75 km of shoreline that included exposed sandy tidal flats, 34 km contained oil residues. Exposed sandy tidal flats occurred more frequently than these statistics show, because the transects terminated at the end of the oil. Thus, the presence of an exposed tidal flat seaward of a beach that was visibly clean would not be recorded; nor when the visible oil ended before reaching the tidal flat.

Moderately Exposed Sandy Tidal Flats


Description
A typical example of moderately exposed sandy tidal flats is shown in the aerial photograph in Figure 20. A field sketch and topographic profile of the site shown in that photograph, produced during the Mt. Mitchell field survey in March 1992, are given in Figures 21 and 22. In 1992, the oiling of this transect extended from the high-tide line offshore for over 300 m. Note the occurrence of multiple sand bars on the middle and outer portions of the flat. It is also clear from the aerial view that the halophytes, which previously occupied about 70 m of the upper sand flat, had not recovered at that time.

Sediments and Oiling
Twenty-three of the 24 sediment samples collected during the 1992 survey on moderately exposed sandy tidal flats studied were composed of either medium-grained (0.25-0.5 mm) or fine-grained (0.125-0.25 mm) sand (Hayes , Michel, and Montello, 1993). In the 2002-2003 study, the average grain size of the sediments on moderately exposed sand flats was 0.48 mm, or medium-grained sand, and the sand was moderately well sorted.

The oiling characteristics of the moderately exposed sand flats changed slowly over time. As seen, for example, on the Mt. Mitchell transect GWS-VII, which was discussed above and is described in Figures 20-23>. The general oiling characteristics of transect GWS-VII changed little between 1992 and 1993. In fact, the hardening of the surface of the oiled bars on the flat made the site look even more impacted two years later. As shown by the photograph in Figure 23, footprints made during the previous year’s survey were still preserved on the oiled surface of the flat. The liquid oil in the crab burrows had been sealed over and was still in a liquid state 2 years after the spill (see Figure 24). Liquid oil in burrows was found in a number of localities during the 2002-2003 surveys, twelve years after the spill.

Water Level Concerns


Future Rise in Global Sea Level
Any consideration of the characteristics of the sandy beaches and tidal flats of the study area should involve some consideration of future changes in sea level in the Gulf, particularly the potential for sea level rise (SLR). A study by the U.S. National Oceanic and Atmospheric Administration Laboratory of Satellite Altimetry shows that between 1992 and 2008 global sea level has increased at the rate of 3.2 mm/year. This type of measurement is more reliable than land-based tide gauges, because of the tendency of many land areas to rise and/or fall as a result of tectonic influences (e.g., plate tectonics). A summary by the International Panel of Climate Change (IPCC, 2007) considered several scenarios for sea level rise by the year 2100. They were: B1 = 38 cm; A1B = 48 cm; and A1F1 = 50 cm. Scenario A1B, considered by some to be the most reasonable conclusion, assumed very rapid economic growth, with a global population that peaks in mid-century and there is a rapid introduction of new and more efficient technologies, at a balance across all sources. Scenario A2F1 is the same, but the use of fossil fuels continues to be intensive. As research on this topic continues at a rapid pace, hopefully more accurate predictions can be made.

Local Tectonic Influences
Another factor that impacts the actual potential sea level rise (SLR) along any shoreline is local tectonic influences (i.e., whether the land is rising or falling). There have been a number of studies that have dealt with land elevation changes around the Gulf area in the past 5,000 years, the time when sea level reached near its present level around the world (in the open ocean).
These numbers follow:

  • (1) Qatar – Rising at rate of 1.1 mm/year (Vita-Finzi, 1982). Please be reminded that the present rate of SLR is 3.2 mm/year, so the rising land in this area only nullifies one third of the impact of SLR, assuming both factors remain relatively constant.
  • (2) Al Jubail, Saudi Arabia – Rising at the rate of 0.3 mm/year (Ridley and Seeley, 1979).
  • (3) Musandam Peninsula, Oman – Sinking at rate of 8.5 mm/year (Vita-Finzi, 1982).
  • (4) Indian Ocean shoreline of Oman – Rising at rate of 0.35 mm/year (Hayes and Baird, 1993).

The rate we determined in Oman (near the UAE border) was based on measuring topographic beach profiles in which an “old raised beach ridge” presumably formed about 5000 years ago was 177 cm higher than the present high-tide line.

Clearly, the tectonic changes listed above are relatively minor compared to SLR, except for possibly along the Strait of Hormuz.


References Cited:

  • Defense Mapping Agency, USA. 1975. Sailing directions for the Persian Gulf: Defense mapping agency, Hydrographic Center, Washington, DC, 352 pp.
  • Dickinson, W.R. 1974. Plate tectonics and sedimentation. In: W.R. Dickinson, (ed.), Tectonics and Sedimentation. Tulsa: Society of Economic Paleontologists and Mineralogists, Special Publication 22, pp. l-27.
  • Edgell, H.S. 2006. Arabian deserts: Nature, origin, and evolution. Dordrecht, The Netherlands, Springer, 592 pp.
  • El-Baz, F. and R.M. Makharita. 1994. The Gulf War and the environment. Gordon and Breach Science Publishers S.A., Philadelphia, pp. 131-161.
  • Hayes, M.O. and W.F. Baird. 1993. Shoreline erosional/depositional patterns in Oman. In: Coastal Engineering Considerations in Coastal Zone Management, American Society of Civil Engineers, NY, pp. 144-158.
  • Hayes, M.O., E.R. Gundlach, and C.D. Getter. 1980. Sensitivity ranking of energy port shorelines. In: Proceedings of the Specialty Conference Ports ’80, American Society of Civil Engineers, Norfolk, VA, pp. 697-709.
  • Hayes, M.O., J. Michel, and T.M. Montello. 1993. ROPME sea oil spill nearshore geochemical processes study. Volume 1. Distribution and weathering of oil in intertidal and subtidal sediments for year 1 (1992). Prepared by Research Planning, Inc. Marine Spill Response Corporation, Washington, DC, MSRC Technical Report Series 93-002.1, 230 pp.
  • IPCC. 2007. Fourth assessment report of the intergovernmental panel on climate change. Cambridge University Press, Cambridge and New York.
  • Jordan, T.E. 1981. Thrust loads and foreland basin evolution, cretaceous, western United States.
  • American Association of Petroleum Geologists Bulletin, 65(12), 2506-2520.
  • Lees, G.M. and N.L. Falcon. 1952. The geographical history of the Mesopotamian plains. Geographical Journal, 118, 24-39.
  • Meteorology and Environmental Protection Administration (MEPA). 1987. An assessment of biotopes and coastal zone management requirements for the Arabian Gulf. MEPA Technical Report No. 5, Coastal and Marine Management Series, Kingdom of Saudi Arabia. 249p.
  • Meteorology and Environmental Protection Administration (MEPA). 1991. Coastal surveys summary report. Unpublished report.
  • Michel, J., M.O. Hayes, T.M. Montello, and T.C. Sauer. 1994. ROPME sea oil spill nearshore geochemical processes study: Distribution and weathering of oil in intertidal sediments for year 2 (1993). Prepared by Research Planning, Inc. Marine Spill Response Corporation, Washington, DC. MSRC Technical Report Series 94-009, 140 pp.
  • Reynolds, R.M. 2002. Meteorology and climate, section 1: The Gulf ecosystem: Biogeophysical setting. In: N.Y. Khan, M. Munawar, and A.R.G. Price (eds.), The Gulf Ecosystem Health and Sustainability, Backhhuys Publishers, The Netherlands. 510pp.
  • Ricketts, E.F.; J. Calvin; J.W. Hedgpeth, and D.W. Phillips. 1985. Between Pacific tides. Fifth Edition. Stanford, California: Stanford University Press, 652 pp.
  • Ridley, A.P. and M.W. Seeley. 1979. Evidence of recent coastal uplift near al Jubail, Saudi Arabia. Tectonophysics, 52:319-327p.
  • Research Planning, Inc. (RPI). 1977. Beach processes study: Master plan final report, Kuwait waterfront project. Research Planning Institute, Inc., Columbia, SC. Sasaki Assoc., Inc. Technical Paper 1, 53p.
  • Research Planning, Inc. (RPI). 2003. Oiled shoreline survey in support of the marine and coastal damage assessment. Columbia, South Carolina, Research Planning, Inc. Publication, RPI 055/2003/008, 387p.
  • Vita-Finzi, C. 1982. Recent coastal deformation near the Strait of Hormuz. In: Proceedings of Royal Society of London. A. Mathematical and Physical Sciences, 382(1783), 441-457.

East Florida’s Barrier Islands: Natural vs. Man-Made; By Dr. Charles W. Finkl

Figure-10LR

By Dr. Charles W. Finkl

Florida is world famous for its white sandy beaches, as seen in Figures 1 and 2 which respectively show a portion of Fort Lauderdale Beach in Broward County and part of the beach at the Breakers Hotel in Palm Beach County. Many if not most of the beaches in southeast Florida have been renourished. That is, they are man-made beaches that are periodically replenished with sand dredged from the floor of the ocean. In spite of the fact that most beachgoers are unaware that many Florida beaches are artificial, even more people do not realize that the barrier islands along the southeast Florida shore are man-made coastal features, much larger and more imposing than the beach itself.

The notion that beaches are artificial may not be that big of a surprise, especially to those beachgoers who have seen ocean dredges at work pumping sand onto the beach from the seafloor. The reason most folks are not aware of artificial barrier islands is that they were formed when artificial inlets were cut in the 1920s. What follows is the interesting story of how this happened. In fact, what we see today is the unintended result of this inlet cutting that occurred many decades ago; a process that changed the face of the southeast Florida coast forever. These artificial barrier islands are not true barrier islands at all, but the result of these coastal engineering efforts.

Geomorphology of the Southeast Florida Coast


The central and northern Atlantic coasts of Florida are commonly depicted as a chain of barrier islands (Figure 3) that are separated by capes and headlands (e.g. Cape Canaveral). In contrast to this coastal depiction and perhaps surprisingly, as described below, the southern coast is mainly mainland and keys. The transition from barrier islands to mainland occurs near Palm Beach whereas the transition to keys takes place at Miami (Key Biscayne, the northernmost key). So what happens in between, from northern Palm Beach to Miami? This stretch of coast is not insignificant when one considers that about five million people live on this man-modified shore (e.g. Finkl and Makowski, 2013).

The geomorphological processes associated with barrier island systems are different from those of mainland coasts, and require a closer look. The distinction is important because the coastal frameworks of barrier islands, mainland shores, and keys develop their own sets of morphodynamic processes that respond differently to coastal resource management. Barrier islands, for example, are formed and maintained by such processes as island lowering and thinning, washover, rollover, and migration (e.g. Masselink, Hughes, and Knight, 2011; Pilkey 2003; Pilkey et al., 2011). Mainland coasts and keys are stabilized by bedrock; they are susceptible to inundation and erosion, but do not rollover or migrate like natural barrier islands.

” What we see today is the unintended result of this inlet cutting that occurred many decades ago; a process that changed the face of the southeast Florida coast forever…”
— Dr. Charles W. Finkl

Definition, Recognition, and Development of Coastal Barriers


It is fair to ask how barrier islands are defined and how are they separated from concepts of mainland. The question is not rhetorical, theoretical, or academic and answers may be obtained without resorting to the points of view of those with opposing arguments, even though they may be persuasive in their opinions. As we are not interested in opinions, or legal and administrative (jurisdictional) definitions, the scientific facts will suffice to draw some conclusions that may contradict popular conceptions. But, before we can consider characteristics of barrier islands, it is perhaps worthwhile to briefly review the geomorphological setting of the southeast Florida coastal environment.

The coastal configuration of southeast Florida is controlled by the underlying bedrock (e.g. Banks et al., 2007; Banks et al., 2008; Finkl and Banks, 2010; Hoffmeister and Multer, 1968). Several studies (Finkl and Warner, 2005; Finkl and Andrews, 2008 Lovejoy, 1983, and Precht and Miller, 2007) report that local exposures of bedrock formations (i.e. Miami Oolite, Key Largo Limestone, Miami Limestone, late Pleistocene coral reefs, and the Anastasia Formation), (see Banks et al., 2007; Hine, 2009; Randazzo and Halley, 1997), provided bedrock control of seafloor morphology and shoreline position. Finkl and Warner (2005) specifically showed how the geomorphological configuration of the present-day southeast Florida shoreline in relation to the continental shelf was ultimately influenced by pre-Holocene bedrock structural transitions. Banks (1999), Finkl (1993), and Finkl and Andrews (2008) also showed how depressions in the bedrock provided accommodation space for marine sediments between shore-parallel lithified paleoshorelines (now drowned offshore or buried onshore by Recent sediments) (Lovejoy, 1983).

Small rocky ridges along the shelf break, with up to 10 m vertical relief, mark positions of paleoshorelines that were referred to as “prominent sonic horizons” in the seismic reflection profile surveys conducted by Duane and Meisburger (1969a). Numerous lower-relief, shore-parallel ridges, separated by depressions, occur shoreward across the shelf. The depressions between the rock outcrops contain marine sediments that have accumulated to 15 m in thickness, forming a series of linear step-like inter-reefal sand flats between paleoshorelines (Banks et al., 2008; Duane and Meisburger, 1969a, 1969b; Finkl, 1993; and Finkl, Andrews, and Benedet, 2003). The inter-reefal sand flats contain calcarous sands, limestone gravels, coral fragments, and intercalated clays and slits (DaPrato and Finkl, 1994). Gorsline (1963) and Macintyre and Milliman (1969; 1970) previously showed that continental shelf sediments in this area contain an oolitic component along the seaward side of the reefs with concentrations of planktonic Formainifera and pteropod shell remnants on the descending slope of the continent slope. The relict rocky ridge coral reef facies surrounding these inter-reefal flats rise up from the underlying bedrock to form the Florida Reef Tract (FRT) (Macintyre, 1988, and Moyer et al., 2003). Studies of the FRT (e.g., Agassiz, 1852; Lidz et al., 1991a, 1991b; Hoffmeister and Multer, 1968; Murdoch and Aronson, 1999; Precht and Miller, 2007; Shinn, 1963) describe a shelf-edge coral reef system that extends 260 km alongshore, which becomes most extensively developed offshore of the Florida Keys. Today’s so-called ‘barrier islands’ parallel the offshore coral reefs and linear exposures of bedrock on the seafloor. As described below, coastal sediments (shoreface, beach, dune, and marsh sediments) have accumulated on top of landward extensions of these bedrock highs.

Natural Barrier Islands Versus Man-Made Barriers


This is the backdrop to the man-made barrier island setting. At first glance, the coastal plain barrier islands of southeast Florida appear to meet the formational requirements laid out by Pilkey (2003) and Swift et al. (1985): a rising sea level, a gently sloping mainland surface, a supply of sand, energetic waves, and a low to intermediate tidal range. The brief comments here are not a story about island genesis (see discussion in Pilkey, 2003), but rather an explanation of how the ‘barrier islands’ of southeast Florida were man-made. The interesting point is that the Holocene evolution of the coast did produce, according to the criteria listed above, barriers. Although some may have been barrier islands, most appear to have been barrier spits connected to the mainland as evidenced from early aerial photography. Figure 4 is an oblique aerial photograph (looking from the southeast towards the northwest across the shore) of Lake Mabel that was eventually turned into Port Everglades. Comparison with Figures 5 and 6, modern views of the coast, shows the extent of coastal modification that took place with urban-industrial development along the shore and in coastal wetlands. Going back to Figure 4 (circa 1925), note the jetties at the New River inlet to the north (upper right hand corner of photo) (now closed). The spit originally extended southwards past Lake Mable to the town of Dania Beach, some 9 km down coast. The intact barrier beach – dune system, clearly visible in the lower left corner of the photo, has now become a true barrier island due to beheading by inlet cutting. The upper or northern part of the barrier has already been destabilized by the stabilization of the New River inlet. Because the barrier was starved of its alongshore sediment supply, it became unstable and migrated shoreward becoming welded to the mainland. By 1935, the process was essentially complete and the remaining portion of the barrier island (formerly a barrier spit) had become welded to the mainland.

At this time what remains is a mainland coast. But, this is not the end of the story. At about the same time, the Intracoastal Waterway (ICWW) was being dredged through freshwater marsh at variable distances inland from the shore. These marshlands were part of the Florida Everglades that nearly reached the coast (Finkl and Restrepo, 2007). Comparison of Figures 4, 5, and 6 shows the location of the ICWW that is more or less parallel to the shore and which lines up with the natural waterway on the north side of Lake Mabel (now the turning basin of Port Everglades, a major cruise ship, container, and petroleum port).

By 1935, the ICWW was completed along this section of coast and a new, modified biophysical setting had been created by inlet dredging, harbor development, and dredge and fill operations. This setting thus appeared to show a shore (beach-dune system) that was backed by wetlands that were cut by man-made canals. The land area between the shore and the ICWW was gradually referred to as the ‘barrier island’ (Finkl, 1993). The true barrier spits and islands, from a geological point of view, had long disappeared and this strip of land thus became known as the barrier island. The process of inlet dredging and stabilization along with construction of the ICWW continued all along the Florida east coast, southwards to Miami and northwards up the coast past Palm Beach and further.

When Is a Barrier Island a Barrier Island?


Such a question to average beachgoers may seem inconsequential and without merit for further consideration as a beach is a beach. Or is it? As we know from global studies of beach morphodynamics, there are many different kinds of beaches from both a process and morphology (shape) point of view (e.g. Benedet, Finkl and Klein, 2004; Finkl, 2004; Short, 1999; Davis and FitzGerald, 2004). Beaches are also different in terms of composition and grain size as well as geographic positions from tropical low latitudes to high polar zones. Beaches can be very different and so can barrier islands. Pilkey (2003), for example, has summarized the main types of barrier islands as Arctic, bay mouth, sandur, composite, accidental, man-made, and lagoon barrier islands. Barrier islands thus occur in a wide range of environments and beaches are normally associated with them. In the case of these examples from Florida, it is interesting to note that the land area between the shore and the ICWW is treated as a barrier island by the State of Florida for administrative purposes. Jurisdictional or not, this has nothing to do with the geological perspective of barrier islands. The case is interesting because the designation of ‘barrier island’ carries connotations as to modes of formational development, use, protection, hazards, and management. The political or managerial point of view is divergent from the geological facts because we now know the pathway of historical evolution for these coastal strips of land.

Most barrier islands are composed of unconsolidated sediments that rest unconformably on a variety of substrates, as seen for example in the Carolinas and elsewhere when a barrier migrates shoreward and overrides marsh sediments. The Florida east coast so-called barrier islands are rock cored and cannot migrate. Rather spectacular examples of the rock core is seen in the 15-m deep road cut thru the Anastasia Formation (Lovejoy, 1983) on the island of Palm Beach (Figure 7), or the rocky coastal cliffs at Blowing Rocks Preserve (Tequesta) on Jupiter Island (Figure 8). On the shore, the Anastasia Formation is characteristic of a wave-erosion coast with notches forming at the bottom of sea cliffs. There are often small sea caves and most cliffs have a wave abrasion platform at the base, which is often covered with sand.

” The Florida southeast coast beaches are in fact sand starved, and must be periodically renourished so that the shallowly underlying limestone bedrock is not exposed by erosion to produce a rocky shore. …”
— Dr. Charles W. Finkl

Small sea arches occur at the base of promontories that jut into the ocean making for a very interesting seascape. With an age of about 130,000 years old, the Anastasia Formation is the youngest lithified (solid rock) marine deposit found along Florida’s coast. It was formed during what scientists call the Marine Isotope Stage 5 (MIS 5e) when sea level during an Interglacial time was a few meters higher than today. In addition to occurring on land and along the shore, the Anastasia Formation also occurs offshore on the continental shelf where it forms exposed bedrock surfaces that serves as a template for geomorphological development of seafloor features such as structural sand flats and interesting reticulated patterns (Finkl, Benedet and Andrews, 2005).

The rocky nature of the shore is also illustrated in Figures 9 and 10 where rock outcrops of the Anastasia Formation form structural sand flats and more or less flat bedrock surfaces that are clearly visible in the nearshore at the South Lake Worth (Boynton) Inlet and at the Boca Raton Inlet, respectively. Both figures show former shoreline positions associated with bedrock highs on the south or downdrift sides of the stabilized inlets. The exposed bedrock is darker colored than the lighter colored surrounding sand on the seafloor.

Inspection of the shore along the southeast coast shows that the beaches are perched on top of limestone bedrock (Miami Limestone or the Anastasia Formation). Note the dramatically perched beach in Figure 8 as an extreme example. Prior to the late 1970s (Miami Beach was first renourished in 1977), native beaches typically had about 2 m of sand over the limestone bedrock (based on beach probe studies by the author), but now most beaches have been artificially renourished by dredging sand from the seafloor increasing the thickness of berms that in turn gives a false impression of this coast’s sand-worthiness. The Florida southeast coast beaches are in fact sand starved, and must be periodically renourished so that the shallowly underlying limestone bedrock is not exposed by erosion to produce a rocky shore. This would be bad for tourism and consequently enormous amounts of money are spent to maintain the appearance of natural beaches.

From a bureaucratic point of view the southeast coast is regarded as a barrier island and the beaches as barrier island beaches. This regulatory definition is in sharp contrast to a geological point of view that relies on coastal configuration, morphology, and coastal dynamics that define this as a mainland shore. The barrier spits and barrier islands have long ago disappeared (cf. Figure 4)> at the hands of coastal engineering efforts to cut and stabilize inlets.

The beaches, whether designated as barrier island beaches or mainland beaches, are still beautiful and constitute major tourist attractions. Although most beachgoers do not know the difference between a barrier island or a mainland beach along the southeast coast because of misinformation, for all intent and purposes the beaches look great but do not function as a true barrier-island beach. And because most beaches are artificially renourished and the so-called barrier islands are engineered, the southeast coast of Florida is a good example of an artificial or man-made coast. It is replete with artificial beaches and man-made barrier islands. Although not specifically studied by the author, it is suspected that the central and northern Florida coasts may also be lithologically controlled but construed as true barrier islands.

Implications of Barrier Island Misidentification


The misidentification of a man-made barrier island coast for a mainland coast may seem like a moot point or a trivial matter, but this is not so because managerial procedures appropriate for natural barrier islands and beaches cannot be applied to man-made coasts. Neither barrier island rollover is physically possible, nor are other natural processes such back stepping or regression, when the ‘barrier’ is rock cored. Beach erosion is a problem along the southeast coast, as in many other areas, but erosion over the short term can only erode beach and dune sand back to bedrock. The problem is, however, exacerbated by construction too close to the shore. Erosion of the rocky cliffs takes place over the long term and is not an urgent problem. One might have thought, however, that the presence of rocky shores does not match the definition of a barrier island composed of unconsolidated sediments. Nonetheless, with the present situation of misidentification of the present shoreline there exist numerous implications for proper management of these coastal segments.

What’s in a Name or Does a Name Matter?


In order for speech or writing to be intelligible to others, beliefs about the word must largely cohere. The term barrier island has specific meaning to geologists, but when the term is misapplied because of incomplete understanding or misidentification of landforms or types of coastal systems, it is a disservice to the public and scientific community. In the example of southeast Florida we see that natural barrier islands and spits became welded to the mainland shore as a consequence of engineering works. The mainland shore today is fixed by limestone bedrock and the land area between the ocean and ICWW does not constitute a (natural) barrier island in the traditional sense of the word (see Swift et al., 1985) because it is rock cored.

This technical clarification does not, however, detract from the beauty or allure of south Florida’s perched beaches that are artificially maintained on what we now clearly recognize as man-made barrier islands. Tourists and beachgoers can enjoy them just as before, but now with a more informed view of reality. One would hope that politicos and natural resource managers come to appreciate the significance and importance of scientific and technical terminology. Words have meaning and their application or misapplication has consequences in the real world. We should not be indifferent to the truth because misidentification of geologic features by application of incorrect terminology leaves researchers unequipped to distinguish truth from falsity in matters that most concern them.


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Perranporth Beach, Cornwall, England; By Norma Longo

perranporth-beach-full

By Norma Longo, 
Nicholas School of the Environment, Duke University, Durham, North Carolina

Cornwall, the southwesternmost county of England, is famous for Land’s End, St. Michael’s Mount, St. Ives, numerous beautiful beaches, and a past history of extensive mining of a variety of minerals, particularly tin and copper (1). In Cornwall, some beaches and mining activities are so interconnected that it’s practically impossible to study one without garnering some knowledge of the other.

Facing the Atlantic Ocean and Perran Bay on the north coast of Cornwall is Perranporth Beach, one of the best in the country, a popular beach for surfing, rock- pooling, horseback riding, walking, and engaging in various other sporting activities. Recently, online reviewers ranked Perranporth as the 13th best beach in the UK (out of over 300 beaches) in the 2013 Travellers’ Choice Beach Awards (2). (Figure 1 – Perranporth Beach.) The beach can be very crowded in primary bathing times (July and August) but can seem practically deserted during other parts of the year. The wide stretch of sand is a great place to play fetch with dogs, and dogs are allowed all year, with leash restrictions only during July and August on the main, busiest part of the beach, known as Perranporth Village End. (Figure 2 – dogs on beach)

The beach is oriented northeast-southwest and the coastal setting includes dunes, cliffs, tidal pools, and a stream mouth, plus various reminders of Cornwall’s ubiquitous mining history. As with most seaside towns, tourism is important to the area, with The Watering Hole, a popular pub located right on the beach, plus a variety of hotels and B&Bs available nearby. The Royal National Lifeboat Institution (RNLI), an almost all-volunteer life-saving force, has a lifeguard station situated on the beach, with safe swimming areas patrolled and flagged as needed during the busier months. (Figure 3 – RNLI)

The beach lies between two rocky headlands, Ligger Point to the northeast and the smaller Droskyn Point toward the southwest. The entire county is underlain with mine shafts and tunnels, and at the site of Wheal Droskyn at Droskyn Point, the Millennium Sundial was constructed overlooking the beach, displaying the fact that Cornwall time is about 20 minutes behind Greenwich Mean Time (3). Inevitably, time and tide wait for no one. When the tide is out, Perranporth Village End to the southwest and Perran Sands to the northeast are combined into a beautiful 3-mile (5 km) stretch of light tan sand about 770 yards (700 m) wide, but at high tide this length of beach is split into two separate areas by rocks (called Flat Rocks) protruding onto the beach. (Figure 4 – Flat Rocks) The incoming tide covers the flat beach quickly and cuts off passage via the beach from the Ligger Point headland to the widest section of the beach in front of the pub and the car park.

“Mining in the area of Perranporth Beach was what used to bring people here, but now it’s a surfing paradise and a popular tourist holiday spot.”
— Norma Longo

Perran Sands is backed by cave-riddled cliffs and rocky shoreline features at the base of large, vegetation-covered sand dunes, the Penhale Sands (also called Penhale Dunes and Gear Sands). (Figure 5-dunes-WateringHole-river) These dunes are mobile to some extent, encompass over 1500 acres (625 ha), and stretch for about a mile inland (4,6). In addition to animals such as rabbits, Shetland sheep and ponies, the dunes host a variety of dune grasses, wildflowers, and insects (e.g., numerous butterfly and moth species). Unfortunately, they are sometimes marred by commonplace litter strewn where beachgoers have picnicked and left their debris. A golf course and an army training camp are located atop the dunes, which are also used for orienteering competitions. A portion of one of the UK’s numerous public footpaths, the South West Coast Path, runs along the top of the dunes and cliffs, with part of the path on the beach itself (5). According to Cornwall Council, the Penhale Sands are the highest dunes in Britain, reaching to a maximum of about 300 feet (90 m), with a depth of nearly 165 feet (50 m) of sand before rock is reached (6).

The dune field is designated a Special Area of Conservation by the European Union (EU) and an Important Plant Area by Plantlife, a wild plant conservation charity based in England that describes the area as being part of the most extensive dune system in Cornwall. The dunes, composed of windblown calcareous shell fragment sands which create highly calcareous soils with little organic content, extend about 2.5 miles (4 km) in length. Because of the beneficial lime content, these dune sands were mined by farmers in past centuries, for use on their lands (7). Plantlife also notes that four very rare plant species (Babington’s leek, wild leek, fragrant evening primrose, and Shore-dock) grow at Penhale Dunes, and the dunes are also home to at least 19 species of moss and 66 lichen species, including the scrambled egg lichen. Climate change and sea level rise will almost certainly be threats to this important ecosystem (8).

The name Perranporth is derived from St. Piran, an Irish priest who brought Christianity to the area, built the earliest Christian church, and was named the patron saint of Cornwall and miners. Various legends tell of his arrival in Cornwall and his possible discovery of tin and tin smelting. The sand dunes hold the now-buried ruins of St. Piran’s Oratory and an ancient Celtic Cross, as well as the remains of several famous mine workings, primarily in the foredunes area (9). The Great Perran Iron Lode, worked in the 19th and early 20th centuries, crossed underneath the area, with openings onto the beach and in the dunes (10). Other mines there included Wheal Ramoth, a tin mine, and Wheal Vlow, both with adits exiting onto the beach. A 1908 map of the area shows three adits that exit onto Perran Sands and Perranporth beach. (Figure 6 – 1908 map) Most mine entrances on top of the dunes are now covered with protective grates or have been buried under up to 65 feet (20 m) of sand, to prevent adventurous passersby from falling down open shafts (4).

Mining in the area of Perranporth Beach was what used to bring people here, but now it’s a surfing paradise and a popular tourist holiday spot. From the car park, the Ponsmere Bridge takes you across a river that runs through the beach. In winter, storms and high tides have been known to change the course of the river and leave the bridge with only sand underneath (7). The river is formed by the Bolingey and Perrancoombe streams that originate in farming lands inland and combine on the beach before flowing into the ocean. Downstream, stepping stones create a neat walkway across the shallow river from the broad, sandy beach to the sea arches and the rocky cliffs toward the southwest, making for a beautiful and interesting landscape. (Figure 7 – stepping stones).

A sand scarp of a foot or more in height runs alongside parts of the river where children commonly play. The river runs south of the solitary outcrop, Chapel Rock, ancient site of Chapel Engarder (the ruins of which remained there at least in 1733) (11). The rock is completely surrounded at high tide and is eroding away, like parts of the cliffs nearby, a process that will be amplified by sea level rise. A salt-water bathing pool covered with mussels and other sea creatures is a prominent feature on the ocean side of the outcrop. (Figure 8- pool) A news article from The West Briton noted that construction of this pool was approved by the Perranzabuloe Parish Council in October 1958. It would be a place where youngsters could learn to swim. The pool fills with sea water at high tide and the sun warms it. Rectangular in shape, approximately 35 feet (10 m) long and 20 feet (6 m) wide, portions of three sides of the pool are concrete while the remaining sections are part of the rock itself. This interesting landmark is one of several special tidal sea-water pools that can be found on the UK coasts (12).

Cornwall’s Atlantic Coast beaches consist of sand derived from the erosion of rocky shores and cliffs and include shelly sand washed in from the sea floor by swell. Ancient slates and sedimentary rocks provide an immediate sediment source, as does the reworking of the dunes and stream sediments. Historians believe that tin ore (cassiterite) was first taken from streams by very early miners, the Ancients, before true underground mining began (13). By the 18th century, underground mining, with shafts, adits, and engine houses with steam engines, became the most important occupation in Cornwall.

South of the river is Droskyn Point, an eroding cliff that was mined for copper and tin in the early 1800s. (Fig. 9 – Droskyn Point-Chapel Rock) Writing about Perranporth, A.K.H. Jenkin (1962) said that “the scouring action of the sea upon the beaches has on rare occasions revealed deep pits which could not possibly have been excavated under present conditions, covered as they would be now by every high tide. It is assumed that these were, in fact, the bottoms of old workings which were sunk when the cliffs stood many feet above them before their erosion by the action of the sea”(14). With the removal of the Droskyn Lode by miners of long ago, some of the mine shafts were dug to a depth of 10 or 15 fathoms (60 or 90 feet) below sea level. Tin and wolfram were frequently concentrated by tidal action on the beaches, allowing some miners to earn a meager living by collecting the tin particles from the sand. Action of the sea eroded away shafts and adits leaving large sea arches with rocks on the shore below them (14). (Figure 10- sea arch) Mine adits here have remained open to view in the cliff face, apparently since the 1800s. A report by Cornwall Mining Consultants Ltd. in 2010 found 24 mine features on the beach (15).

The site at Droskyn Point (known as Sunny Corner) is commonly enjoyed by families with children for exploring the rock pools and the cliffs where mining took place. Undoubtedly, some disasters occurred in working Cornish mines (16), and tragedy struck again, in 2010, when an accident at Perranporth took the life of a youngster. On a family outing to the beach, an 11- year-old girl was boosted up by her father into an unfamiliar and dark opening in the cliff while they were exploring the rock pools below. She walked about 15 feet into the pitch-black tunnel, then tumbled into a hole, reported to be 30 feet deep, with a pool of water at the bottom. The adit and shaft are remnants of mine workings in the cliff (17). Around the corner, facing the beach and Chapel Rock, danger signs had been posted and some adits were already blocked. (Figure 11 – adit & sign) Now, a metal grate also blocks the entrance to that particular adit.

“…the Penhale Sands are the highest dunes in Britain, reaching to a maximum of about 300 feet (90 m), with a depth of nearly 165 feet (50 m).”
— Norma Longo

All the same, Perranporth Beach will likely always be a popular destination for surfers and other holiday-makers. The swash zone here is gently sloping, with spilling breakers ranging from 2.5 to 7 feet (0.8 to 2.2 m) in height, and the beach is macrotidal (tidal range > 13 feet (> 4 m)) with a mean spring tide of about 16 feet (5 m) (18).
Macrotidal beaches, besides creating good surfing conditions, often form bar and trough systems offshore, but waves breaking over the nearshore bars also create a rip circulation which is anti-clockwise at Perranporth. A study of rip current circulation at this beach found that the currents were controlled by gaps in the bars (19). Rip currents can be a particular problem with the outgoing tides, sometimes giving the lifeboats and lifeguards a workout. Danger flags are evident on the beach when rips are active, with the strongest rip flows around low tide. A news report noted that in 2012, Perranporth Beach was the busiest spot for the RNLI in Cornwall, as lifeguards dealt with 615 varied incidents, including rescues from rip currents, and 2013 will likely be just as busy (20).

Beach visitors might be surprised to learn that some mine shafts went many miles under the sea, and a number of beaches, including Perranporth, once were dotted with mining-related buildings. (Figure 12-1890 mining buildings on beach) According to Bill Trembath (7), “Wheals (mine workings) in the area are complex and some are very ancient. In some cases, mining villages have been buried/drowned by sand and some adits exited onto the beaches.” In the first half of the 19th century, Perranporth was dominated by two great copper mine complexes, Wheal Leisure and Perran St. George (21). A song called “Two Mighty Mines” recalls the troubles that purportedly occurred between these two Perranporth mines. Wheal Leisure sued the other, claiming encroachment of mineral rights, i.e., wrongful removal of copper ore, and won. In retaliation, the Perran St. George adventurers stopped pumping the water out and both mines flooded.

Two Mighty Mines
Two mighty mines Near two hundred years ago Where Perran men did copper find ‘neath Perranzabuloe.
Two mighty mines With their workings intertwined The tunnels of Wheal Leisure And of Perran Great St. George.
And all of the time The water lay in wait Soon to reclaim its dark domain The depths obliterate.
Two mines at war Over tons of copper ore Won from the veins Wheal Leisure claimed St. George should now restore.
Two mighty mines Each dependent on the other To pump the lower levels dry As soon they might discover.
And all of the time The water lay in wait Soon to reclaim its dark domain The depths obliterate.
Two mighty mines With their limits undefined They went to law both hoping for The judge to draw the line.
Two mighty mines But St. George they had to pay A fine of such proportions Their investors wouldn’t stay.
And all of the time The water lay in wait St. George they stopped their pumping. Left Wheal Leisure to her fate.
Two thousand men Worked underground to stay alive Two thousand men thrown out of work So Perran mining died.

Words and music © Nigel Hallworth 2010 (used with permission) (22)

Cornish mining had a boom-and-bust lifestyle throughout the 19th century, with the last great boom around the 1870s-1880s. With Cornish mining coming to an end, primarily due to foreign competition, many miners left Cornwall for North America, Australia, Peru, and other parts of the world. Some arrived on the scene and worked in North Carolina, where the first gold in the United States was discovered (23). The gold mining in North Carolina didn’t last, and neither did the mining in Cornwall, where most mine workings ceased by the end of the 19th century. Nevertheless, the potential for mining to affect today’s beaches remains.

An entrepreneurial Cornish company, Marine Minerals Ltd. (MML), has plans to harvest tin from the seafloor sand offshore between St. Ives and Perranporth. During the county’s mining days, some metals would have made their way onto the beaches and into the ocean. MML anticipates an average of around 8,800 tons (8,000 tonnes) of tin-bearing sand per month will be brought ashore (24, 25). “MML believes that there are millions of pounds worth of tin reserves off the north coast of Cornwall which are in high demand as a valuable resource with applications in many global technological industries” (25). MML has performed environmental studies by taking core samples from the seafloor along the coast, but as of this writing, the project permitting or licensing process has not been completed. The proposed project would last 10 years and is estimated to cost £15M (about $23M). However, the possibility of sand mining along the coast is disturbing to some, particularly surfers in the area. Even though MML states that their high-tech method of extraction will not damage the environment, the Surfers Against Sewage (SAS) group is campaigning against what they term the dredging or mining of seafloor sand to extract remnants of tin, because they believe the activity will change the shape of the seafloor and thus the shape and size of the waves (26, 27). (Figure 13 – waves)

The north coast of Cornwall is credited with having eight of the best 100 surf spots in the world. Perranporth, one of these eight, has three quality breaks (“big, grinding, low-tide barrels”), one at Droskyn Corner, the best off Chapel Rock, and the third at Flat Rocks (28). Cornish waves break on sand bars offshore, so the shape of the seabed is essential to the important surfing and tourist industry of the area. MML states that they will use one ship that will vacuum the sand off the bottom well beyond any breaking waves, more than a half-mile (km) from shore, where it will be in about 30-65 feet (10-20 m) or more of water. On board the ship, the tin will be extracted from the sand, and the remaining sediment will immediately be returned to the sea bed. It sounds fine in theory, but the results may not be satisfactory. The company does say they will not undertake the actual project unless it can be done in an “environmentally, socially and economically viable way” (24, 25).

“Cornwall’s Atlantic Coast beaches consist of sand derived from the erosion of rocky shores and cliffs and include shelly sand washed in from the sea floor by swell.”
— Norma Longo

SAS members, however, believe that the environment is at risk. One possibility is that increased turbidity in the water could have a detrimental effect on some marine organisms. The surfers reportedly are “concerned that disrupting the sediment close to river mouths could reanimate pathogens associated with sewer overflow discharges and heavy metals,” negatively impacting marine animals such as seals, lobsters, and fish in the area (26, 27). Several studies on other beaches of the world have shown that beach sands as well as waters may contain a variety of pathogens that can cause severe gastrointestinal and other illnesses (29-31). This could possibly be a factor at Perranporth, given the river there, and it is uncertain whether the beach and river sands have been tested for pathogens. Since 1986, the Bolingey and Perrancoombe streams themselves have been monitored upstream from where they join, with the finding that their water quality is worse during and after heavy rainfall, which means that the bathing water quality downstream can be reduced. Also, the outfall from Perranporth sewage treatment works (STW) discharges to the sea about a mile (1.3 km) southwest of the bathing water. However, this discharge is disinfected to protect bathing water quality. The UK Environment Agency (EA) tests the bathing waters at Perranporth weekly during the bathing season for E. coli and Enterococci, and the waters of the ocean at this location are said to be clean “the majority of the time” (32).
Notably, throughout the European Union, information about water quality and potential sources of pollution is required to be displayed at beaches and inland waters that have been identified as bathing (i.e., swimming) waters (32).

Sand mining or vacuuming by MML is still in the planning stages, and some Cornish people look forward to the new jobs that the company says will be created, believing that the mining will be good for the area. Ultimately, fishing, a historically important occupation in Cornwall, could be adversely affected by the offshore sand mining, as could wave action and, as a result, the occupation of professional surfers in the area. Tourism probably will not suffer significantly, as the beautiful beach and town will still be there. (Fig. 14 – Perranporth seen from the beach) Given that larger waves from more numerous storms in the North Atlantic likely will come with the sea level rise, what does the future hold for this beautiful beach? Only time will tell. (Figure 15 – Sunset over Perranporth Beach)

Acknowledgments:

Material and comments have been gratefully received from Angela Broome, Librarian Archivist, Courtney Library and Cornish History Research Centre, Royal Cornwall Museum; Kim Cooper, Principal Library Officer, Cornish Studies Library, The Cornwall Centre; Nigel Hallworth, acclaimed Cornish musician/singer/ songwriter; Peter Joseph, Curator, Trevithick Society, Camborne, Cornwall; Gina Longo, intrepid UK traveller who introduced me to Cornwall and Perranporth; William Neal, Professor Emeritus, Grand Valley State University, Allendale, Michigan; and Orrin Pilkey, Professor Emeritus, Duke University, Durham, North Carolina.

References:

View map of Perranporth Beach, Cornwall, UK here.

Note: URLs were current at the time of publication.

Cemeteries in the Sea; By William J. Neal & Orrin H. Pilkey

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By William J. Neal, Grand Valley State University, Allendale, MI and Orrin H. Pilkey, Duke University, Durham, NC

Sea level is unaware of the political controversy over the reality of climate change; the sea continues to rise. Many of the world’s shorelines continue to retreat landward, as they have been doing since the great melt-off of the continental glaciers that began about 10,000 years ago. In the short-run experience of human history, or even shorter spans of an observer’s lifetime, we often measure the continuum of the sea’s advance using human structures as reference points. Old lighthouses are classic examples. These structures were built to withstand the rigors of storms, placed in positions where those rigors were known agents of erosion, and at the time of construction, the position of the lighthouse with respect to the shoreline was mapped with precision. Comparisons of today’s shoreline to those recorded on the old maps, with respect to the lighthouse position, show us how far and how fast the shoreline has retreated, or, in some exceptional cases, has accreted.

“Cemeteries by the sea are silent sentinels. Like lighthouses and coastal fortifications, they bear dates of former times when they were on high and dry land..”
— William J. Neal & Orrin Pilkey

The Morris Island Lighthouse near Charleston, South Carolina, was built in 1876, about 1,300 ft. (370 m.) inland from the water’s edge. By 1940, it was on the beach, and today the lighthouse sits 2000 ft. (610 m.) on the sea floor offshore in front of the island (figure:Morris Island lighthouse). The island migrated out from under the static lighthouse, in part because of sea-level rise, but the main cause for the island migration was the loss of sand supply to the island due to the construction of the jetties at the entrance to Charleston Harbor in 1889. In contrast, North Carolina’s Bodie Island Lighthouse was originally built in 1872 near the north side of Oregon Inlet. Today the lighthouse stands two miles away from that inlet which has migrated to the south. Had this lighthouse been sited south of Oregon Inlet, it would have fallen into the sea long ago as did its two predecessor light structures.

Many lighthouses were built with the expectation that they would someday be lost to the sea. A good example is the Montauk Lighthouse on eastern Long Island, New York. Legend has it that when this structure was built in 1796, George Washington required that it be located far enough back from the bluff edge to last for 200 years. It was built 300 ft. back from the edge of the bluff, and, sure enough, by the 1990s coastal erosion had moved the bluff edge 200 ft. toward the lighthouse. Old mapped water-line surveys from 1838 to 1956 showed an average retreat rate of 1 ft./year, about the distance anticipated 200 years ago. In contrast, the Cape May Lighthouse, New Jersey, is the third such structure, the first two having fallen in to the sea – perhaps reflecting that their builders were not as aware of coastal retreat as was George Washington.

Cemeteries as References for Shoreline Retreat


In our coastal work over the last four decades we’ve observed another common historic landmark by which to mark the pace of coastal retreat (and sea level rise), namely, cemeteries. Cemetery headstones are marked with dates, and sometimes the burial grounds are noted on maps, again allowing an approximation of how rapidly the shoreline has retreated by inundation and/or erosion. Inundation is often indicated by the presence of a cemetery in a salt marsh, obviously not a place that burials would take place.

The cultural tradition of burial is that a cemetery is a place of respect for the dead, and for many, even that it will be there at the end of time. Cemeteries aren’t sited with the expectation that our loved ones’ remains will be falling into the sea! Yet, we have seen numerous examples where this has been the case. Shackleford Bank, North Carolina, now part of the Cape Lookout National Seashore, was once home to the settlers of Diamond City and Wade’s Hammock who, after experiencing 3 powerful hurricanes in 1899, packed up and moved to the mainland at the beginning of the 20th Century, leaving behind three small cemeteries, only one of which remains today. This site is near the eroding back side of the island. One tombstone reads, “Remember Youth when this you see, prepare for death and follow me.” The rejoinder to this once common epitaph is, “To follow you I’d be content, if only I knew which way you went.” Not far to the north, at the ghost town of Portsmouth village on Portsmouth Island, another of the Outer Banks barrier islands, an old cemetery is nearly completely lost. Again, located on the back side of the island, the sea-level rise has flooded what was once dry land from the sound side, and the only evidence of the cemetery is a few remnant stones in the salt marsh. Clearly, this 19th century cemetery was not originally placed in the marsh, so its current location is evidence of sea level rise.

The custom of some churches on the Outer Banks of North Carolina is to place headstones with the epitaphs facing the road. For example, the tombstones in the cemetery at Rodanthe, North Carolina, dating from the 1900s to present, face Highway 12, but the older stones face the opposite direction, toward the sound or back side of the island. Apparently, prior to the late 19th century, the road ran along the back side of the island, and the stones faced that road. Then, rising waters eroded that road away, and a new one was built on the seaward side of the cemetery. Since then, the newer headstones have been given the traditional orientation and now face the new road (Hwy 12).

Farther north, in Chesapeake Bay, a cemetery was once part of the small town of Broadwater on Hog Island, Virginia, but the small barrier island literally migrated out from under the town. Most of the houses, hotels and even a lighthouse fell into the sea, although a few buildings were moved to the mainland. Years later, fishermen reported catching tombstones in their nets as they trawled over what was once island.

Sinking Cemeteries


Hog Island is but one of Chesapeake Bay’s disappearing islands, once inhabited but abandoned as they were slowly eroded and/or inundated (e.g., Holland’s Island, Sharp’s Island, James Island, Shanks Island, Poplar Island), victims of subsidence and erosion (Los Angeles Times, 23 Oct. 1987: 4).

“Cemetery headstones are marked with dates, and sometimes the burial grounds are noted on maps, again allowing an approximation of how rapidly the shoreline has retreated by inundation and/or erosion. .”
— William J. Neal & Orrin Pilkey

Little is left of Holland’s Island and its coffins have been reported floating out to sea. In 2007, the Washington Post (13 Feb.:A.1) reported that “water is evicting the dead” on the Bay’s Eastern Shore, noting in particular the cemetery being claimed by the eroding bank of Hoopers Island. The article noted 12 burial sites around Chesapeake Bay that were being washed away, or destroyed from below due to rising ground water, often salty, that kills trees which then topple, exposing graves. As a result of storms in 1996, two small cemeteries near Dorchester (Bishops Head) were washed away, resulting in people “progging” (searching the marsh) for “dentures, bones and coffin parts.” In addition, older Indian burial sites are being lost (Press of Atlantic City, NJ, 4 Mar. 2007). The Western Shore of the Bay has similar examples (e.g., Gloucester County, Jenkins Neck, VA: Daily Press, Newport News, VA, 14 Oct. 2006: C2).

Reports of floating coffins don’t always indicate erosion. Coffins sometimes virtually float up to the ground surface when inundated by storm surges. On Ocracoke, North Carolina, after a hurricane flooded the island, two coffins (a husband and wife, side by side burial) floated up and were found at the surface of the cemetery after the storm passed by and the flood receded.

Chesapeake Bay is somewhat of a geologic anomaly, resulting in the region sinking, so the rate of sea-level rise is 4 to 6 inches greater than the projected global sea-level rise for the century. This subsidence is due to the fact that during the ice age the great ice sheet depressed the lands to the north and caused the Chesapeake Bay region to bulge upward. After the ice retreated, the land to the north rebounded, while to the south, what is now the Bay area readjusted by sinking (isostatic adjustment).

Delta Subsidence


Of course, some towns do not pack up and move, but try to hang on in the face of rising sea level and coastal erosion. In some cases, they live in the face of a rising sea level out of necessity – fishermen of the small communities built on the levees of the fingers of deltas that extend into their working environment, like the Mississippi delta. And deltas are in double jeopardy because they contend with both global sea-level rise and even more severe local sea-level rise due to the sinking of the delta caused by natural compaction of delta muds and drilling for water or oil. Unfortunately, the existing high ground is not long-lived in the time frame of a community’s history, and sinking turns dry-land cemeteries into flooded wetland marsh or submerged memorials (figure: NOAA photo of graves-marsh-birds). Nevertheless, the local residents can be surprised by this loss of familiar dedicated ground, even knowing that deltas are unstable environments.

In late 2012 and early 2013 there was a rash of media reports of cemeteries in south Louisiana being swallowed by the sea. The ABC News website ran photos of crumbling crypts, broken headstones in overwash sand, offshore grave sites, and crypts in marsh land (Louisiana Cemeteries Swallowed by Sea, ABC News). An Associated Press article quoted a resident saying, “We did not bury people in marshes. We buried them on high ground.” (Grand Rapids Press, MI, 6 Jan. 2013: D5).The Montgomery Advertiser, AL (5 Jan. 2013: 3) noted 11 cemeteries in Jefferson Parish repeatedly flooded after Hurricane Katrina, and more than a dozen other cemeteries in Lafourche, Terrebonne, and Plaquemines Parishes have “succumbed to tidal surge.” Caskets float away during flooding and human remains become separated and dispersed. Tree kills by salty ground water cause toppling that adds to the losses.

Indeed, the graves dating from the 19th century to more recent times were built on high ground above the marsh and well-back from the shore, but they are now threatened at the water’s edge or falling into ruin in and below water level. The land loss is due to the combination of delta subsidence, global sea level rise, and the loss of protective marshes due to canals dredged in the 1930s that allowed salt water intrusion. Waves and storm surge during hurricanes raise the water levels even more and erode into the cemetery sites (e.g., 7 feet of loss at the Leeville cemetery during Hurricane Isaac, 2012). After Hurricane Isodore, 2002, boaters found coffins floating in the marsh in Terrebonne Parish (The Courier, Houma, LA, 5 Mar. 2012). The ultimate culprit, however, is sea-level rise, magnified by local subsidence and storm erosion.

Other Coastal Cultures


Other cultures also are at the shore by necessity. Alaskan coastal subsistence communities, entire Pacific Islands, and the coastal fishing communities of most continents, especially 3rd world nations, all provide examples of cemeteries going into the sea.

In Barrow, Alaska, a burial site (due to an accident) was discovered when a boot containing a skeletal foot appeared on the face of an eroding bluff. The foot turned out to belong to one of 5 family members who were crushed in their Inupiat winter house by a sheet of ice that was pushed ashore by winds. The family became known to archeologists as the Frozen Family See: The Frozen Family of Utqiagvik: The Autopsy Findings). The ice push catastrophe occurred as much as 500 years ago. One of the well-preserved female bodies proved to be a lactating female but no baby was found at the site.

Army Corps of Engineers “Alaska Baseline Erosion Assessment” studies indicate that numerous subsistence coastal communities are threatened by coastal retreat, including their cemeteries, an important part of their culture (e.g., St. Paul on one of the Pribilof Islands, Metlakatla on Annette Island, and Ouzinkie on Spruce Island in the Gulf of Alaska, to name a few).

On Majro Atoll, in the community of Majuro in the Marshall Islands at least two cemeteries were toppling into the sea within town limits and no apparent effort was being made to save them (Marshalls, Kiribati, Tuvalu noted in Assoc. Press release, 12 June 2010) (figure: Marshall Islands photo). Reports of coastal storm damage to cemeteries on Pacific islands are common news items (e.g., the Independent, London, 10 Jan. 2001; BBC, 25 Dec. 2008).

The Global Pervasiveness of Threatened Cemeteries


A search of the world-wide web provides ample global examples of cemeteries in or at the edge of the sea. Google any of the following names: Caye Caulker Cemetery, Belize; Cemitério a beira mar, Brazil; Cemitério do Apiques, Brazil; Caherdaniel Cemetery, Abbey Island, Kerry, Ireland; Banjul Cemetery, Gambia, Africa; ; a cemetery on the Ivory Coast of Africa (San Francisco Chronicle, 13 March 1989: B6), or beach front Municipal Cemetery, Lubang, Philippines.

Hurricane Wilma, 2005, unearthed coffins from coastal cemeteries in the Bahamas (Palm Beach Post, 1 Nov. 2005: 8A). In Canada, a January 1998 storm exposed bones from the cemetery in Terence Bay, Nova Scotia, worthy of news note because this cemetery is where many of the victims of the SS Atlantic’s sinking were buried in 1873 (McClean’s, 1 June 1998: 70). And by the late 1990s, the sea was claiming graves on the shore of Colac Bay, New Zealand; both more ancient graves but some from the 20th century (Southland Times, Invercargill, NZ, 28 April 1999: 9; 23 June 1999: 5; 1 July 1999: 10).

St. Mary’s Graveyard, Whitby Abby, Yorkshire, England (famous as the setting for Bram Stoker’s story of Dracula), at the edge of a crumbling cliff, was receiving attention at least as early as 2000 (Coventry Evening Telegraph, 1 Dec. 2000: 2) when it was reported that gravestones were being moved from the cliff edge and tests were being conducted to determine the slope stability. Boulders were brought in from Scandinavia to ‘protect’ the bottom of the cliff from coastal erosion. But the problem was not solved, and as noted in The Guardian article cited above, bones were coming out of the cliff face as graves were exposed, and in January 2013 another major landslip put more of the cemetery in jeopardy.

The continued loss of St. Mary’s graveyard comes as no surprise for the Yorkshire Coast of England. Books have been written documenting the loss of at least 29 coastal towns that once flourished along this coast, but only recently have studies shown that the rate of erosional retreat has accelerated (The Guardian, 24 Sep. 2012). A 14th century account of a once thriving town, Ravenser Odd on the England’s east coast, noted the sea’s destruction of the town chapel and its associated graveyard between 1349 – 1360. Old church records are historical documentation of such losses, for example, Dunwich and its ancient churches have all been lost to the sea, along with cemeteries such as that associated with All Saints Church. The last remaining gravestone fell from the cliff’s edge in the early 1990s. Even more ancient burial grounds around England, Scotland and Wales are being lost to the sea or threatened as archaeologists race to study these sites before they too are erased.

However, we generally do not place the same sense of threat from the rising sea level as measured by losses over hundreds or thousands of years, but the loss of cemeteries that are a century or less old should generate a greater sense of urgency that sea level is rising at a rate that calls for planning a rational retreat.

Responses to Cemetery Losses


An interesting aspect of the pervasive global loss of cemeteries to the sea is that the cultural responses are the same as when buildings are threatened by erosion, falling into one of three categories: 1) harden the shore and construct a ‘protective’ barrier against the sea, 2) move the cemetery, or 3) let the cemetery fall in, but in some cases gather historic information before complete loss:

1. Save Our Cemetery: Along the shores of Galveston Bay, Texas, where sea level rise is particularly rapid due to land subsidence, a church put up a road sign pleading for contributions to a special fund to save their cemetery (figure: Save Our Cemetery banner, Texas). “Save our cemetery” is usually another way of saying “build a sea wall” – thinking that will be a solution. A micro-example is a tiny cemetery on the south end of Daufuskie Isand, South Carolina, where development resulted in properties being threatened by on-going coastal erosion. In response, home owners built seawalls which in turn shifted the erosion points to the ends of the walls. By 2004, there were lawsuits over the structures, and erosion of the bank threatened a cemetery. Around 2005, bones were found along the shore, and consideration was given to moving the cemetery, but it was decided to keep its existing site (McClatchy-Tribune Business News, 17 Aug. 2006: 1; 25 Aug. 2006: 1; 11 Oct. 2006: 1). By 2006, graves were falling in as erosion worsened. Controversy arose over the delay in constructing a seawall, and a year later the delay continued, although a 400-foot rip-rap seawall had been approved (McClatchy-Tribune Business News, 18 Oct. 2007; 8 Nov. 2007). Moving the cemetery would have been more timely, less costly, and a longer term solution. Yet, again and again, shore hardening is seen as the better choice.

“The global pervasiveness of cemeteries going into the sea is evidence of the global sea level rise..”
— William J. Neal & Orrin Pilkey

That previously noted Colac Bay, New Zealand, cemetery was ultimately fronted by a ‘protection work’ but it appears that when a three-meter tide hit at a later date, the wall shifted the erosion point and the coastal road suffered damage (The Southland Times, Invergargill, NZ, 12 July 2000: 12; 21 Aug. 2001: 1). And as previously noted, the imported rip-rap at the base of St. Mary’s cliff in Yorkshire did not stop the cliff-face retreat. Many subsistence villages previously mentioned initially opted for seawalls of various types, but in the end they are still faced with the relocation solution. And one of the great ironies we observed was a chunk of man-made rip-rap on the shore of San Juan, Puerto Rico, made up of cemented broken gravestones. That wall too had failed and been replaced by a bigger wall. Similarly, an uncemented pile of tombstones, forming a small revetment, was noted on the landward side of Wrightsville Beach, a North Carolina barrier island. Local opinion concerning the tombstones was that they were thrown out because of misspelled names!

2. Relocate: At Maarup Kirke, on the west coast of Denmark, the grave diggers move graves one-by-one as the sea gnaws away the crumbling cliff (The Independent on Sunday, London, 19 June 2011: 74). The community of Port Heiden on the shore of Bristol Bay, Alaska, has moved two of the settlement’s cemeteries since 1981, according to the USACE. In some cases, the only solution is to move entire villages, including moving the cemetery, or abandonment. But even developed shorelines face this dilemma. At North Cove, Washington, the Pioneer Cemetery was moved after a citizen’s campaign to save the site from loss to coastal erosion.

3. Let Nature take its course: Like the early settlements of the Outer Banks and the island communities of Chesapeake Bay, the cemeteries were left behind when the people resettled to the mainland. Similarly, when small island nations must abandon their disappearing islands there is no real choice other than abandonment of cemeteries. The same is true of all low-lying coastal communities where ‘high ground’ will never be high enough to preserve a cemetery and shore-hardening is folly. The Louisiana delta parishes are learning this lesson, but with a response that has an eye on history and remembering the dead. A regional mapping project has been undertaken by the Louisiana Sea Grant Program to map the locations of all coastal cemeteries, focusing initially on those closest to the water, e.g., Pitre in Cocodrie, Holy Family in Dulac, and Isle de Jean Charles (The Courier, Houma, LA, 8 Mar. 2012). By January 2013, the project had documented 43 sites in 13 of Louisiana’s 16 coastal parishes, including the Cheniere Caminada Cemetery near Grand Isle which holds a mass grave of approximately 700 people killed in the community by the 1893 hurricane — the marsh is now at the edge of this cemetery (HoumaToday.com, 12 Jan. 2013). Historical documentation by this mapping project will be of value to future historians and genealogists and serves as a good model for facing the cultural and economic reality of the global sea-level rise.

Similarly, a historic cemetery (1737-1920) that is being lost to erosion on Rainsford Island in Boston Harbor is being studied for conservation by determining erosion rates, flood potential, and using ground penetrating radar (GPR) to identify unmarked grave sites (Gontz, A.M., Maio, C.V., Wagenknecht, E.K., and Berkland, E.P., 2011, Assessing threatened coastal sites: Applications of ground-penetrating radar and geographic information systems: Journal of Cultural Heritage, v. 12, 451-458).

If the Dead Could Speak


Cemeteries by the sea are silent sentinels. Like lighthouses and coastal fortifications, they bear dates of former times when they were on high and dry land. And even if the dead can’t speak, headstones in or on the edge of the sea or in marshes tell a story of the sea’s advance. The global pervasiveness of cemeteries going into the sea is evidence of the global sea level rise. Individual graveyards add witness to other processes that have accelerated the local/regional rate of that rise, both natural and man-made. Examples of natural processes include flooding during storms (e.g., storm surge during hurricanes & nor’easters) and tsunamis, subsidence (sinking of deltas, isostacy, earthquakes), and wave attack — the plague of all shorelines affected by sea-level rise. In almost all cases, waves are the erosional agent, inducing shoreline retreat by the beach moving onto former upland, or through the waves undercutting bluffs and cliffs, resulting in gravity-induced landslides and slumps. Rising sea level results in a rise in the water table, allowing salt-water intrusion to reach tree roots, causing kills that result in tree blow-downs which can ‘uproot’ graves. Examples of humans contributing to cemetery losses are mainly from building shore-hardening structures (e.g., seawalls, groynes) that cut off the sediment supply to protective beaches which then erode, exposing adjacent cemeteries. In some instances the erosion may be due to up-drift sand mining, and flooding may be due to dredging of marshes or removal of protective wetlands such as marshes or mangrove stands.

That ancient burial grounds have met this fate is not surprising, but the loss of more recent cemeteries or grave sites in the short span of one’s lifetime is another wake-up call that the sea-level rise is real. If the dead could speak, they would tell us that locating a cemetery in a vulnerable coastal location is a poor choice, and trying to hold back the sea is folly. And would they not ask, why do we do the same with buildings?


Rising Seas Wash Dead Away from Marshall Islands Graves (06-06-2014)

Washaway Beach, Cape Shoalwater; By Eddie Jarvis

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By Eddie Jarvis,

The Outer Banks. New Orleans. Surfer’s Point. Cape Shoalwater. All of these places may be swept away a hundred years from now but I’d be willing to bet you’ve only heard of the first three. However, despite its relative anonymity, Cape Shoalwater, Washington is the fastest eroding stretch of land on the west coast, maybe even the entire Western Hemisphere.

It’s OK, the only reason I’ve heard of it is because I live nearby. But if erosion to the tune of over 100 feet a year for the past century doesn’t get you some national publicity, I don’t know what will. Granted, Cape Shoalwater doesn’t haveMardi Gras or the Governator but it’s not as if the place is deserted. 100 years ago and a mile out to sea there was a lighthouse, coast guard station, cannery, cemetery and a post office. Now there’s a gas station that doubles as a video store and a small Indian casino. Cape Shoalwater will never be mistaken for the Big Easy, but to the 435 people that make up the town of North Cove, Washington and the nearby Shoalwater Bay Indian Reservation, its home. Although if the next century is anything like its predecessor, home will be on the bottom of the Pacific Ocean quicker than you can say Army Corps of Engine…

“Condemned houses sit precariously on small bluffs, waiting to fall into the icy Pacific at any moment, serving as a constant reminder that at Washaway Beach it’s not if your house will fall into the ocean, it’s when.”
— Eddie Jarvis

The stretch of coastline from the southern tip of Grays Harbor to the mouth of Willapa Bay is truly Washington State’s lost coast. Not only is it eroding at a phenomenal rate, but the American Dream died around these parts right around the time the spotted owl got itself endangered.

On a rare sun drenched winter day I found myself driving down State Highway 105 past a steady stream of dilapidated trailers, the occasional cranberry bog and some very rustic beach cottages on my way to Cape Shoalwater, in particular a place known locally as Washaway Beach.

What the 9th Ward is to New Orleans, Washaway Beach is to North Cove, albeit on a slightly smaller scale. Dilapidated ground water pipes and severed rebar poke out of the sand. An old World War 2-era gun turret (that was later used as a septic tank, but that’s a different story) serves as a tidal pool during low tide. Freshly fallen Cedar and pine trees lounge on the beach, waiting to be carried away during the next winter storm. Condemned houses sit precariously on small bluffs, waiting to fall into the icy Pacific at any moment, serving as a constant reminder that at Washaway Beach it’s not if your house will fall into the ocean, it’s when.

The mysterious case of the disappearing beach can be traced back to the year 1895, when the Army Corps of Engineers built the first jetty on the entrance to the Columbia River. Probably unbeknownst to them, the Corps had just altered the landscape of every beach lying to the north by changing the natural process of sediment migration. For thousands of years the beaches of the Pacific Northwest had relied on sand from the mighty Columbia to replenish themselves after a winter full of harsh, violent storms that ate away at the coastline. The jetty trapped and altered the flow of the sand, thus leaving the places like Shoalwater Bay starving for its natural defense against erosion.

Years later the Corps exacerbated the already insufficient supply of sediment by dredging the entrance to Willapa Bay, creating a sizable channel. The new channel trapped any incoming sediment that was directed towards Cape Shoalwater. To top it off, 274 dams have been built on the Columbia River Basin in the last 80 years, trapping sediment intended for all Pacific Northwest beaches, not just Cape Shoalwater. In all, the carrying capacity for sands on the Columbia River has been reduced by 2/3rds.

The coastline’s inability to regenerate itself means it is at the mercy of Pacific storms. The more storms, the more erosion occurs. Not a good situation to be in when you live on the doorstep of the powerful Pacific Ocean. During the winter of 2009-10 a weather phenomenon called El Nino Modoki (Modoki meaning replica in Japanese) in which the equatorial Pacific is unseasonably warm, caused massive storms on the Washington coast. The weather phenomena hit North Cove hard, causing an average of 345 feet of shoreline to erode along its beaches. At the end of Warrenton Cannery Road (Just off Highway 105, in case you were wondering) 605 feet were lost. On Washington’s lost coast, erosion has become a way of life. As local resident, photographer and blogger Ericka Langley puts it, “at Washaway, you don’t really own the land. The water owns you.”

Much to the chagrin of the locals, the state and federal governments have done little to stop, or even slow down the erosion. Because of the low cost housing and the area’s impoverishment, North Cove is easy to ignore. In 1976, a local resident named Don Pickinpaugh fought to relocate the eroding Pioneer Cemetery. The Army Corps of Engineers recommended against structural solutions to the erosion problems because they were not economically justified and the environmental impacts were not known. The response from the Corps sums up condescending nature of local and federal government relations. The Corp’s response now sits on display at the local Tokeland Hotel while the Pioneer cemetery was moved across the highway.

In 1995 the federal government was forced to step in when the expanding tidal channel threatened to undercut Highway 105, but their solution left many environmentalists shaking their heads. Led by a local cranberry farmer named Nick Wood, who coincidently lives next to the stretch of highway in question, lobbied the Federal Highway Administration to build $27 million dollar groin protecting Highway 105…and Nick Wood’s cranberry bogs.

“On Washington’s lost coast, erosion has become a way of life.”
— Eddie Jarvis

At the time, Dr. Orrin Pilkey, then Director of the Program for the Study of Developed Shorelines at Duke University, claimed the groin was “…one of the larger atrocities built on the American shoreline in the last couple of decades. There is every possibility this will ultimately increase the rate of erosion. What it will do to the channel is anybody’s guess. I’ve lost sleep over that.”

The groin is even more egregious when you consider for $13 million dollars more, or .034% of the FHA’s budget, Highway 105 could have been relocated…at the expense of Nick Wood’s cranberry bogs.

Almost immediately after the groin was built, the Shoalwater Bay tribe’s square-mile reservation began to erode substantially. In response to pressure from the tribe, the Army Corps of Engineers pledged $12 million and implemented a plan to use dredged sand to replenish a barrier dune offshore of the reservation. Tune in next week when I interview Nick Wood and taste the world’s most expensive cranberries.

The unwilingness of the Army Corps of Engineers hasn’t stopped the residents of North Cove from trying to save their homes. In the 1960’s locals built a makeshift jetty out of junk cars then proceeded to sue the Corps, claiming the dredging of Willipa Bay had directly influenced the erosion on Washaway Beach (which it had). The jetty was completely destroyed after the first winter storm and the lawsuit was eventually dismissed. More recently, a concerned homeowner has built a large seawall around his house, much to the disdain of his neighbors. The seawall is apparently doing its job, but the property itself will be on an island sometime in the near future as the beach around it continues to retreat.

Maybe if it were million dollar beach houses falling into the ocean instead of double wide trailers falling into the ocean things would be different. According to the National Oceanic and Atmospheric Administration the federal government spends an average of $150 million a year on beach re-nourishment and preventing erosion but the majority of the money goes to vacation getaways such as Palm Beach, Florida or Ventura, California. Two cities that will never be mistaken as North Cove.

Meanwhile, life on Cape Shoalwater continues the way it has for the past century, the beach erodes, homes fall into the abyss while others wait their turn. Residents don’t so much as own property, they lease it from the Pacific Ocean. In fact, North Cove might be the only place in America where housing is more expensive the further you get away from the beach. Mankind has always been fascinated by nature’s fury and no place is more adept to witness the wrath of a storm than Cape Shoalwater. Asked why people continue to live on such a fickle stretch of Earth, Ericka Langley replied, “It is a reminder of our place in nature. It is more powerful than we are. It is one of the great wild places in the Pacific Northwest.” Ms. Langley should enjoy it while it lasts.

Anclote Key, Florida; By Richard A. Davis, Jr

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By Richard A. Davis, Jr.

Anclote Key is a wave-dominated barrier island on the Gulf peninsular coast of Florida near Tarpon Springs. This is the northernmost barrier in this system of 30 barrier islands and a like number of tidal inlets. It lies about 4 km from the mainland and is in the State Park system of Florida. Because of its relatively remote location and the fact that it must be accessed by boat, the barrier is pristine as Florida barriers go. There is ferry service from Tarpon Springs. It is densely populated during the weekends and it has become a favorite place for campers although camping is primitive with no facilities.

Anclote Key is about 5 km long and only a couple of hundred meters wide at most places. There is a non-functional lighthouse at the southern end that was built in 1887; it operated until 1984 (figure 1; see above photo gallery). Initially there was a resident keeper and then it was automated by the U.S. Coast Guard in 1952. There has been a strong effort to maintain and restore the lighthouse by an organized group of citizens. Recently a residence for a park ranger was constructed.

Geomorphology
This wave-dominated barrier is subjected to a mean annual significant wave height of about 0.5 meters and a spring tidal range of 0.90 meter. It has a channel at each end that functions as a tidal inlet although there are no barriers adjacent on each end of the island. The channels are about 3 m deep and are being filled with sand. The island has an excellent beach that shows accretion although erosion has taken place with washovers during the past few decades. Dunes are present throughout the extent of the island but the maximum elevation is less than 3 meters. Landward of this foredune complex on a relict washover apron are mangroves that comprise the entire backbarrier shoreline.

This barrier island rests on only a few meters of Quaternary sediment which is on top of Miocene limestone. In fact, landward on the mainland these limestones crop out near sea level. Gulfward from Anclote Key the substrate is sand with scattered shells and shell debris. These sediments extend only for a kilometer or so and thin out exposing the same Miocene limestones at about 6 m depth.

Morphodynamics
The aspect of Anclote Key that is most interesting is the rapid rate of change that has taken place over the past few decades and that is continuing. These rapid changes have taken place in the absence of major weather events. The impetus for these changes has been a major change in the offshore environment along this part of the Florida coast. Field observations and aerial photos show that until about 1960 seagrass covered most of the bottom of the shallow Gulf up to only a few hundred meters of the shoreline. This situation existed for a significant reach of the coast from north of Anclote Key to at least the northern part of Clearwater Beach Island, about 25 km in extent.

“…The island has an excellent beach that shows accretion although erosion has taken place with washovers during the past few decades.”
— Richard A. Davis, Jr

Sometime shortly after 1960 these seagrass beds were gone. Multiple reasons have been given including increased water temperature, harvesting by sea urchins and general decrease in water quality. None of these has gained significant acceptance. The bottom line is that the demise of these seagrasses is a mystery. The consequences of their demise has had significant changes in the shore area sedimentation.

Huge volumes of sand were transported shoreward and accreted at the shorelines of multiple barriers along the coast beginning in the 1960s and continuing today. As an example, northern Clearwater Beach Island was experiencing erosion in the early 1950s as was the case for much of this coast. A vertical concrete seawall was constructed to protect expensive homes that lined the coast. At the present time there is about 200 meters of beach and dunes in front of this seawall, all due to natural accretion.

Anclote Key itself has experienced considerable sediment accretion. It was a narrow barrier in the early 1970s (figure 2). The north end of the island was initially the most affected by this additional sand (figure 3). The demise of the sea grass community released the sand substrate to mobility and the wave climate moved it to the shoreline. Longshore currents in this area persist from the south to north, thus the huge additional sediment on the north end of the barrier. Its northern movement was halted by the tidal channel.

There was also accretion on the south end of Anclote Key but not as much as on the north. The old boat dock used by the lighthouse keeper and the Coast Guard was rendered useless by this accretion. Historical data show that little change in the size and shape of the island took place until this release of sediment in the 1960s (figure 4).

Although no hurricanes impacted this area since 1921, there was a tropical storm, Elena (1984), that passed offshore heading toward the Florida panhandle. Because of the nature of the shelf gradient offshore of Anclote, there was a modest surge and washover did take place on the north end of the island where dunes had not yet been developed (figure 5).

Little happened to Anclote Key morphology until the late 1990s. Huge amounts of sand where transported toward the shore of the southern part of the island in the form of large ridge and runnel systems. These did have some benefit of relative high energy in the form of winter cold fronts. During these frontal passages the strong wind is from the north leading to southerly sediment transport. This was combined with formation of ridge and runnel morphology which has become a rather stable because of its elevation well above high tide (figure 6).

There are indications that Anclote Key is slowly evolving into a drumstick barrier because of the multiple ridges that have developed (figure 7). These ridges are not making their way to the shoreline very rapidly and the possibility does exist that a major storm could destroy them and spread the sand over a large area.

At the present time these ridges are becoming stabilized to the point that vegetation is beginning to develop. The beach on the island is in good shape. Beaches on this part of the Florida coast tend to accumulate considerable Thalassia after winter storms (figure 8). This situation indicates that there is still significant seagrass offshore of Anclote. Perhaps storms caused the removal of the seagrass in the early 1960s.


Summary
Anclote Key has been in existence for about 1500 years based on a coring study by Kuhn (Davis and Kuhn, 1985). It has had a fairly consistent morphology and size from most of its existence. Because of a series of events this tendency has changed. Over the past few decades Anclote has experienced major changes in its size and its morphology. There are indications that more changes are likely in the future.

References Cited
Hine, A.C., M.W. Evans, R.A. Davis and D.F. Belknap,1987, Depositional response to seagrass mortality along a low-energy, barrier-island coast: west-central Florida. Jour. Sed. Petrology, 57:431-439

Davis, Jr., R.A. and B.J. Kuhn, 1985, Origin and development of Anclote Key, west-peninsular Florida.Mar. Geol., 63:153-171.