Through The Sandglass

Sylt? No, it's sand (mainly) - a German island on the move

 

A couple of weeks ago, in the midst of the series of posts on Gulf of Mexico berms, I encountered one of those odd coincidences that are odd only because we forget the statistics behind coincidences.

The travel section of the newspaper I was reading had a piece extolling the delights of the endless expanses of dunes and beaches on the German island of Sylt - the tile of this post immediately jumped into my deranged mind. And then, browsing through the geoblogosphere, I came upon an enjoyable post by Ole Nielsen on hooked spits - which highlighted the dramatic sedimentary architecture of Sylt. Ole referred to a recent paper in Sedimentology, and so, intrigued, I took myself off to the Geological Society Library and looked it up. The story is, indeed, intriguing.

Sylt is a form of barrier island and, given the role that these shape-shifting piles of sand play in the ongoing saga in the Gulf of Mexico, they link in to the inexhaustible theme of coastal dynamics. As Ole commented, " Barrier islands are sedimentary islands separated from the mainland by bays or lagoons, and some originate as sand spits. A hooked spit is a landform created by the water currents and may be described as a curved sand bar. In fact barrier island systems often terminate with hooked spit morphologies." Barrier islands come in many shapes and sizes, and the conditions for their formation and their evolution, regardless of whether they terminate in a hooked spit or not, continue to retain many mysteries.

Sylt faces the North Sea and is the northernmost German island - indeed, the mainland across from its northern half is Denmark and the place was Danish until 1864 ; it's 38 kilometres from one end to the other (when last measured) and is connected, artificially, to the mainland. At its northern tip is a beautiful hooked spit. Sylt is geologically young, its core built from debris left over from the melting of ice sheets at the end of the last ice age: these materials were reworked by the onslaught of the rising seas and the main island began to develop around 6000 years ago. Today, the strength and complexity of tides, waves, and currents produces a dynamic playground for sand, dramatically illustrated in low and high tide images, the Wadden Sea to the east festooned with ever-shifting sand bars:  

 

This playground has, as usual, been a difficult place to live. Historically, villages on Sylt have been swept away in storms and inundated by migrating and growing sand dunes, and lighthouses have found themselves in locations no longer effective for their original purpose. The west coast, facing the energy of the North Sea, is subject to constant erosion, the sand being flushed northwards or swept out into offshore bars. The western shoreline of Sylt is now perhaps 10 kilometres east of where it used to be, and today erosion rates reach more than a meter a year; the southern tip of the island has on occasion been severed after a violent storm. But it's an important tourist destination, and so something must be done, and that something, as usual, is beach nourishment. According to Wikipedia, which cites the reference (in German), " Since 1972 an estimated 35.5 million cubic metres of sand have been flushed ashore and dumped on Sylt. The measures have so far cost more than €134 million in total, but according to scientific calculations they are sufficient to prevent greater loss of land for at least three decades, so the benefits for the island's economic power and for the economically underdeveloped region in general would outweigh the costs." Aha - those scientific calculations again..... But these measures require annual replenishment, and so understanding the sand dynamics and sediment budgets of Sylt is important, and this where the four authors, from institutes in Hamburg and on Sylt, of the paper in Sedimentology come in. While the paper itself is not directly available, the PhD thesis of the lead author, Sebastian Lindhorst, that formed the basis for this and other publications, is available to read online.

This work has demonstrated that the sedimentary systems of the main part of Sylt and the hooked spit that forms its northern tip are quite distinct - the spit is growing at the cost of erosion further south; but the way in which the spit grows is far from simple. The work was conducted using ground-penetrating radar, a relatively simple and inexpensive technique that nevertheless has powerful applications in engineering and archaeology (there's quite a good summary on Wikipedia and various commercial companies such as GeoModel). Essentially, the reflections of the radar energy from subsurface layers and objects are recorded when they bounce back to the surface; the reflections are caused by changes in the velocity of the radar waves as the nature of the material they are travelling through changes. Use some clever computer processing and an image of what these subsurface reflections look like can be generated as a profile, a vertical "slice"; the vertical scale on such an image is actually time, in that what you are measuring is the time taken for the radar pulse to travel downwards, be reflected, and return to your recording instrument on the surface ("two-way time", TWT). But, if you know fairly well the nature of the materials underground, then this can all be converted to a depth scale. Importantly, Lindhorst and his colleagues calibrated the radar data with cores and so the character and velocity of different sands, wet, dry, fine-grained, coarse-grained, could be integrated with the radar data.

Here's an example of one of the profiles from their work:

 

The profile at the top is the processed radar data; TWT in nanoseconds (1 ns is a billionth of a second) is the vertical scale on the left, depth in meters, with mean sea level as zero, is on the right. In order to display an image where the components are more clearly shown and interpretable, the whole thing is vertically exaggerated by a factor of five. If it weren't displayed this way, the true-scale version would look roughly like this - accurate, but difficult to interpret:

So, back to the main figure. The profile runs at right angles to the coast of the spit, with the surface topography at the top: the higher ground on the right shows the dunes at the back of the low beach ridges that run parallel to the shore. Now, with experience, local understanding, some cores (and a little imagination), the darker layers that are the reflectors of the radar pulses can be interpreted as successive sedimentary features, and the relationships between them examined. The one significant "layer" that is not a sedimentary feature is the strong, essentially horizontal, reflector that runs across the profile just above sea level: this is the top of the groundwater table, the boundary between dry sands above and wet sands below, a velocity contrast so dramatic that it bounces back a lot of the radar energy. The lower part of the figure is the geological interpretation of the radar data, with the main components of the architecture of the spit identified (my apologies for this only being in black and white, but it's still quite clear). The main elements are all inclined (dipping) towards the right, the shoreline, and represent episodes of growth of the spit, building through time, younger swathes of sand on top of older ones, from right to left (elements G to D).  

But this growth is not continuous, it takes place in episodes, so that surfaces such as F represent the sea floor following a phase of sand build-up where the actions of waves and currents gently scour away at the sand surface. The result is a discontinuity in the sedimentary pile, the next flush of sand being deposited onto that somewhat modified surface. The boundary between the two building events shows up as a radar reflection, with the geometries of the sand layers above and below being slightly different - these surfaces are what are marked on the profile as unconformities. These are vital as they divide the foundation of the spit into successive episodes of deposition and quiescence. But even more important are the features labelled "C." These mark something far more dramatic than the normal ebb and flow of sand deposition: the base of each of these packages of sand is marked by a pronounced discontinuity - the layers beneath are chopped off, scoured, removed, with new piles of sand then dumped on top of them. These "cut and fill structures" are, as the notes on the figure record, telling us of periodic major events, storm surges scouring into the edge of the spit. They are essentially scoop-shaped excavations of the pre-existing sands, filled in, and, like the succession of layers beneath them, recording sequentially younger events from right to left (shorewards).

From numerous radar profiles and the core data, Lindhorst and his colleagues construct a model of how the spit evolves, each major episode of growth, ironically, spurred by an episode of erosion. Each storm surge event leaves a scarp, a small cliff, at the back of the eroded section, and this then acts as a sand trap, leading to the development of "embryonic dunes" along its length. Sand transported along the coast builds up the beach and is periodically recycled out to the edge of the spit. Fast-growing vegetation (largely marram grass, Ammophila arenarea) stabilises the dunes which form "foredune ridges," common features of hooked spits, and a new element of the spit is now firmly established. This sequence of events repeats itself every year or so, and the spit grows.

This work also established that the hooked spit of Sylt is considerably younger than the main island: it began forming perhaps as recently as 1300 years ago. Its growth is supplied by sand eroding from the coast to the south, and that supply has increased by a factor of two or three over the last few decades - most probably as a result of the increased efforts at beach nourishment. So tourists cause landscape changes.....

I'm still not quite clear why this spit is hooked, but presumably it's a reflection of the currents swirling around the entrance to the Wadden Sea, and the dramatically complex playground of sand.

 

[Header image: creative commons license, from Temporalata; satellite images from Eovision; reference for the Sedimentology paper: Anatomy and sedimentary model of a hooked spit (Sylt, southern North Sea), SEBASTIAN LINDHORST, JÖRN FÜRSTENAU, H. CHRISTIAN HASS, CHRISTIAN BETZLER, Sedimentology
Volume   57 ,  Issue   4 , Pages935  -  955;]

Sands of the Solway: Guest Writer, Ann Lingard

 

Late last year, I reported in a couple of posts on my visit to Cumbria and the Solway Firth. The first was a description of the appalling floods that had just occurred and the second, following my ramble on the beach with my host, writer Ann Lingard, was a guest post from her. Now, she has recently written a piece for Cumbria, “Lakeland’s favourite magazine,” and it gives me great pleasure – and great memories - to reproduce it here as another guest post.

 

THE GROUND BENEATH YOUR FEET

THE SANDY SOLWAY SHORE

ANN LINGARD

It's easy to take the Solway's sandy shores for granted: sand, sea, and sometimes sun -- life's a beach, isn't it?

But walk across firm damp sand at Mawbray or Beckfoot, say, and you will see that your footprints have left pale dry treads that quickly darken again with water. Or stand still and stamp your feet up and down, like a seagull 'paddling' for earthworms in a field - and in less than a minute the firm sand turns to 'quicksand' and your feet start to sink as water wells up around them.

Sand mixed with varying amounts of water has strange properties, as sand-sculptors and sandcastle builders know. Sand grains that have settled through the water, like those in the intertidal zone on the beach, become very well-organised and closely packed. When you walk along the beach, you tread on that orderly arrangement and disrupt it and, completely contrary to what you would expect, the spaces between the grains expand. Water drains down into the gaps, so that on the surface your footstep appears paler and drier. Continue paddling in one spot and you enlarge the gaps between the grains, so that more and more water flows in and pushes the grains apart, forming a slurry of quicksand - which may then seize up solid again and cement your ankles in place!

Every time I visit the Solway the shore looks different, as the tides and wind constantly scoop and re-sculpt the sandscape, whether between the tidemarks or higher up, on the edges of the dunes. Longshore drift, the direction in which the tide and waves travel up the coast from Liverpool to the upper Solway, brings animals and objects from further South -- including all kinds of unexpected things washed down by the River Derwent in the terrible November floods. Sometimes the current creates large 'sand-waves' to mark its progress, the hollows between them trapping pools of water when the tide goes out.

But it is in the mid- to lower-shore that the sandscape becomes staggeringly varied and beautiful, the patterns of ripples changing from metre to metre, locked into their patterns until the tide comes in again to re-mould them. Chevrons, fish-scales, dimples: you look around and there doesn't seem to be any logical reason why the ripples near your feet should have a rounded profile but ripples a few metres away are taller and sharper, or closer together. Some ripples, often those nearest pools, have tiny gullies on their faces, perhaps where water drained down and eroded them as the tide went out.

Do the ripple-patterns form when the tide comes in or when it goes out? Do they form and reform all the time they are submerged, according to the ebb and flow of the water? The shore is a good place for stimulating simple questions.

A few years ago, I took some Year 7 and 8 students to look at 'the science of the shore', and a couple of the boys (part of a group who experimented very vigorously with quicksands - to the extreme detriment of their white trainers) became really hooked on trying to find out how sand ripples formed. I thought it would be easy to find an answer -- but was intrigued and even excited to discover that nobody seemed to know. I asked physicist Philip Ball who has written three excellent books on patterns in nature, and geologist Michael Welland who has written a fascinating book called 'Sand, a journey through science and the imagination'; but they both agreed that science has only found partial answers at best.

Michael Welland had been here in West Cumbria to talk to our Cockermouth Café Scientifique, and we had all enjoyed a very entertaining evening with his practical demonstrations of some of the strange properties of sand grains. So I was especially pleased to be able to take him down to Beckfoot the following morning - here, especially, some of the ripple patterns are spectacularly contrasty, the valleys between the ridges being accentuated with a fine black sediment of powdered mussel shell, thrown up from the vast mussel beds on the rocky scars lower down the shore.

And at Beckfoot, too, there is the added delight of walking on the dunes, on sand that was piled and sculpted by the 'aeolian' effect of the wind. Sadly, the seaward side of this nature reserve, part of the Solway Coast AONB, is being continually eroded; the biggest tides in the Solway can rise and fall by as much as 10 metres and if the barometric pressure is low and the wind is strong from the South-west, the waves pound high up on the shore, battering the free edges of the dunes so that large vegetated plates from their margins tumble down onto the sand. But the erosion at least gives you the chance to look at a cross-section through the dunes, to see how they have grown over hundreds of years: the alternating layers of pebbles, sand, dark organic layers of earth and rotted vegetation, more pebbles, more sand -- and the youngest, upper surface bound together by marram grass, silvery sea-holly and other dune vegetation.

If you take a box of muesli and shake it, the biggest heaviest pieces rise to the top - the 'brazil nut effect'. So it is with sand grains of different sizes - they sort themselves out according to size, under the stirring effect of the wind or of water. And the agitation by wind or water has other effects too, a weathering effect so marked that you can tell (with the help of a magnifying lens) whether the grains were deposited in a river-bed or on a dry plain. As we wandered along the beach on that breezy day, Michael took small samples of sand from the shore and from the dunes. A few days later he sent me photographs of the samples as seen through his microscope.

The sample from the dune is full of beautiful rounded and frosted quartz grains, typical of sand blown in the wind; it also contains quite colourful metamorphic rock grains, presumably from the Lake District. The beach sample in contrast is very fine grained and angular, with lots of quartz and colourful rock fragments; sharp-edged and fairly typical of water-borne sand.

So, next time you wander along the beach at Allonby, enjoying one of Twentyman's icecreams, think about the sand beneath your feet. And build a large sandcastle.

[Ann Lingard's latest novel, The Embalmer's Book of Recipes (Indepenpress 2009}, which is set in Cumbria, is available from all good bookshops; see www.annlingard.com for related pictures and reviews. For details of Cockermouth's Cafe Scientifique: www.cafescientifique.org . Sand grain photos by me, others copyright Ann Lingard]

Life and art, sand and glass: the wonders of Difflugia

 

Inspiration has no respect for scale: the images from the Hubble telescope are no more or less wondrous than those from the nano-world. An exhibition at London's Natural History Museum, titled "The Deep," explores the wonders of life in the oceans on all scales, macro, meso, and micro, and included are some exhibits that have been gathering dust in the museum's cavernous store rooms for decades. The creatures in the illustration above are Difflugia pyriformis, a common, but as is so often the case, rather extraordinary, microbe. Difflugia are members of a genus of amoeba or protozoa, single-celled organisms; pyriformis means pear-shaped (as in "things have gone pyriform"), and all Difflugia share an amazing and mysterious common skill that we shall come to shortly.

The central image above is a real Difflugia pyriformis - the ones on either side are glass sculptures of it. These exquisite examples of hand-blown glass biological sculptures are amongst those treasures that have been hidden away at the museum since the Victorian enthusiasm for such things was no longer in vogue. This meticulous art was the work of father and son craftsmen, Leopold and Rudolf Blaschka, whose studio in Dresden was a prolific source of fine glass work during the second half of the nineteenth century. The family had a long tradition of glass-making, originally in Venice, home of the famous Murano glass wrought from the quartz sands and pebbles that cascaded out of the eroding Alps. They moved to Northern Bohemia, now in the Czech Republic, then the centre of craftsmanship in glass and gemstones - making glass eyes for taxidermists was amongst their specialities. Leopold's interest in natural history led to him beginning to make models of flowers in glass and this work became a commercial mainstay of the business when the Dresden Natural History Museum ordered a series of glass sea anemones for their exhibits, and further commissions began to come in from museums around the world. The young Rudolf joined his father in the workshop, and by 1888 the two of them , working alone, had produced a catalogue of more than 400 models, including not only anemones but also squids, sea octopi, cuttlefish, sea squirts and jellyfish; the demand for these lifelike representations reflected the poor preservation methods for real specimens. The Blaschkas' methods were unique and creative, using paint and powdered glass to add further texture and colour to the meticulous sculptures. Examples in the Boston Museum of Natural History were spotted by George Lincoln Goodale who was preparing to set up the Harvard Botanical Museum; Goodale travelled to Dresden and persuaded the Blaschkas to return to their early plant and flower sculptures, the results eventually being the 4000 or so exhibits for the now famous collection.  Rudolf continued to make glass sculptures until a couple of years before his death in 1929; the family secrets went to the grave with him.

In making their Difflugia pyriformis sculptures, the Blaschkas may well have used as a reference illustrations from Joseph Leidy's monograph, "Fresh-Water Rhizopods of North America," published in 1879. A plate illustrating nothing but examples of this species is below, together with a live example:

 

But why should an amoeba like Difflugia pyriformis have such a strange appearance in Leidy's plates, the Blaschkas' work, and in real life? Simply because, like all Difflugia, it builds its shell out of sand. There is thus a delicious self-reference in the sculptures: to replicate the appearance of the amoeba's sandy shell, the Blaschkas used shards of glass, much of which they made themselves, from, of course, sand.

Now, to describe the shell of Difflugia pyriformis as being constructed from grains of sand is not quite accurate - the creature itself is only as large as a single grain of fine sand, and so its construction materials are finer, strictly, than sand. But there are countless species of Difflugia, all tiny but some larger than others. Take, for example, Difflugia coronata:

 

I first came upon this extraordinary piece of living art in the fascinating book by Mike Hansell, "Built by Animals: the Natural History of Animal Architecture." In an online essay, Hansell describes this wonderful creature as follows:

...I give you this structure: It is a sphere composed of a few hundred stones cemented together, on top of which there are seven or eight sturdy spikes, each a cairn of stones, larger ones at the base, smallest at the tip creating a sharp point. At the bottom of the sphere there is a large circular hole ornamented with a pleated collar of particles too small to be distinguishable from the cement that binds them. The diameter of the whole dwelling, for that is what it is, is about 150 thousandths of a millimetre. Smaller than the punctuation mark at the end of this sentence. It is the portable home of Difflugia coronata, a species of amoeba.

An amoeba, as you very likely know, is a single celled organism. The one cell does everything. It feeds, excretes, moves and reproduces and, in this species, it also builds a home. The cell has no nervous system at all, let alone a brain. Can its extraordinary achievement really be said to be building? Well, as the organism's amorphous bulk glides gently round the bottom of some pond, engulfing food particles and growing, it also picks up tiny sand grains that accumulate as a mass inside it. When it grows to a certain size, the cell then reproduces by dividing its body equally into two. One of these inherits the ancestral home; the other is left the bundle of building material. These stones, we know not how, are then moved to the body surface and arranged to create the distinctive architecture of this species. Just enough particles of the right sizes, big and small, have been picked up to accomplish this.

So, here is a single-celled wonder that ingests sand grains and then divides, one half to all intents and purposes turning itself inside-out to create its shell. And we really don't understand how it does it. Inspiration for the art of the Baschkas - and for us? In the same vein of what we might learn from nature's construction methods, reviewed in Hansell's book, the "Ask Nature" project on biomimetic application ideas asks: what are the possibilities of building from the inside out, perhaps for self-healing materials? And what is the glue that Difflugia uses? These are echoes of a couple of nature's wonders that I've written about before, Bacillus pasteurii mending concrete, and sandcastle worms using natural superglue. Inspiration comes on every scale.

 

[The Design Museum and the Corning Museum of Glass have good sites on the work of Leopold and Rudolf Blaschka. Difflugia images reproduced under a Creative Commons License from Ado Out  and Microagua.  Read more on these microbes at the Tree of Life Web Project]

OK, OK, I said I was done - but this is a "must watch"

I may have called a halt to my posts on the berms, but, naturally, I continue to track developments. Via Len Bahr's LaCoastPost that I've cited before, I discovered that a couple of nights ago, Rachel Maddow on MSNBC did a piece on the sad saga, and an interview with Rob Young (whom I have also often quoted), titled "Berm after reading." It's excellent, and I felt I should draw attention to it. Watch it here.

Further sources on oil-eating bacteria - and a line in the sand

I'm a geologist, not a microbiologist, but there's something compelling about the idea of using the natural processes of hard-working bacteria to help clean up the oil - bioremediation. They're doing it already, and always have done, which is why our oceans are not charged with oil from natural seeps. But their appetite is not limitless and they need nutrients to be able to continue their activity, so the concepts of adding to their numbers and boosting their appetite would seem attractive. But of course nothing is simple: there are arguments for and against bioremediation, it does not have a history of success, crude oil contains a vast array of chemicals, not all of which are appetising for all bacteria, and the food for bacteria must be fertilizer - nitrogen and phosphorus - the pollution from which already severely degrades two-thirds of the coastal waters of the US.  And, as an article from the New Scientist, "Clean-up of oil spill may cause long-term damage," notes:

Even benign-sounding proposals like spraying nutrients to boost oil-munching bacteria can be damaging. When Eugene Turner of Louisiana State University in Baton Rouge added phosphorus to plots in a Louisiana salt marsh, it reduced the growth of roots of the dominant grass, Spartina alterniflora, undermining the integrity of the marsh (Estuaries and Coasts, vol 31, p 326).

But there is another point - I've referred to the potential of Alcanivorax borkumensis earlier, but this microbe is not alone. There are hundreds of genera of bacteria adapted to eating hydrocarbons, adapted because hydrocarbons occur so ubiquitously naturally. 

For example, there are recent reports of the discovery of a new strain of a microbe that has been known for a long time, Pseudomonas aeruginosa. The new strain, NY3, was discovered at a site in China contaminated by oil; what it does is to produce rhamnolipids, non-toxic natural "biosurfactants."  As a report in Scientific Blogging describes, "Even at a very low concentration, rhamnolipids could remarkably increase the mobility, solubility and bioavailability of PAHs, and strain NY3 of P. aeruginosa has a strong capability of then degrading and decontaminating the PAHs." PAHs, polyciclic aromatic hydrocarbons, are one of the most harmful components of crude oil. There's another report on this work at Science Daily. But although "this new bacterial strain could be of considerable value in the long-term cleanup of the massive Gulf Coast oil spill," "More research to further reduce costs and scale up production would be needed before its commercial use and the researchers are filing for a patent on the discovery," so who knows what to think.

And, speaking of who knows what to think, the Discovery News site has a piece on another possibility titled "A Florida start-up thinks it can save the Gulf; experts doubt it." So it's, as always, well worth listening to experts, among whom are certainly Ronald M. Atlas, Professor of Biology and Public Health at the University of Louisville and D. Jay Grimes, Professor in the Department of Coastal Sciences, Marine Microbial Ecology, at the Gulf Coast Research Laboratory, University of Southern Mississippi; read their informative commentary at Small Things Considered: the Microbe Blog, and watch their discussion at the American Society for Microbiology's 2010 General Meeting in San Diego.

There are many people and organisations who believe they have a bioremediation solution - the researchers at Bangor University, and a local company, Osprey Biotechnics, among them. And of course that's another problem: well over 100,000 calls have been received at BP's call centre and thousands of ideas submitted on paper. I would guess that there are many that fall into the category of "crank calls" and snake-oil salesmen, but that leaves a huge number that have to be filtered and tested - after all, who would want untested remediation methods randomly thrown at the problem? I'm tempted to say "well, except for the bermers," but I won't, I'm too exasperated. At least, after all the fuss, Costner's centrifugal separators are now being deployed.... 

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

And so, I draw a line, not really in the sand, but under this series of posts on the catastrophe in the Gulf. I have tried to address topics that I know something about, or, if I don't, report the views of people who do. And I have (largely, although some reading between my lines might be revealing) tried to remain objective and to refrain from expressing my personal views. But, quite frankly, I give up. The effort and frustration involved in seeking sense among the eruptive volumes of rhetoric, political posturing, attention-seeking, hypocrisy, ignorance, and hysteria in the midst of a national, local, individual and environmental crisis is simply infuriating. There seems to be no distinction between the critically important and the trivial, the facts and the fictions, or the myths and the realities when it comes to who can make the most noise. The whole mess is a sad reflection on us as a species and on the way our society works.

As and when there is substantive news on the berms or related issues, I'll come back to these topics, but, meanwhile, I shall return to my usual ramblings.    

Berms: the USGS, a timely conference, and some quotes

In earlier posts, I have referred to, and used extensively, the critical contributions of the USGS that are vital to the risk analysis and decision-making associated with the plans for "The Great Wall of Louisiana." And I have expressed concerns that these studies - conducted in their usual thorough and objective way by the people who, after all, know this issue best - have not received the attention that they deserve. Yes, a USGS group has just released the results of its (depressing and alarming) analysis of the volume of the spill, but with respect to management of the response, the headlines have been conspicuous by their absence. Yet the USGS is, arguably, in the best position to be the lead agency in what should be a concerted and coordinated urgent and multidisciplinary blitzkreig on the spill. In the words of Marcia McNutt, Director of the USGS, speaking before the Committee on Appropriations, Subcommittee on Interior, Environment and Related Agencies, the U.S. House of Representatives on May 27 (this is just the introduction, the whole thing being well-worth reading):

The USGS is home to a breadth of multidisciplinary science expertise, an extensive, national, on-the-ground presence, and a wealth of biologic, geologic, geographic, and hydrologic monitoring capabilities and existing data, in scales ranging from microscopic to global. It is USGS’ long-term monitoring capabilities, supported and championed by this Subcommittee, that have positioned the USGS to understand changes in our environment – from water quality to ecosystem composition. The USGS brings its brightest minds and best monitoring and modeling capabilities to issues that present crucial natural resource management challenges. It is this broad capacity combined with a presence in all 50 States and Puerto Rico that enables the USGS to bring science immediately to bear not only in natural hazards such as earthquakes, floods, and volcanoes but also in environmental hazards such as the Deepwater Horizon oil spill. For more than a century, the USGS has been on point in response to natural disasters; it is this experience and expertise that uniquely prepares the agency for dealing efficiently and effectively with the challenge that lies before us today and the challenges that will face us in the weeks, years, and decades to come.

I am not by any means alone in my frustration over science taking a back seat to politics and money. At the end of last week, I received an informative and supportive e-mail from Jim Flocks, a Research Geologist at the USGS Coastal and Marine Science Center in Florida, to which I have referred before. I really appreciate his taking the time to get in touch and giving me permission to copy the following from his message:

Also worthy of note, today was the last day of the State of the Coast conference in Baton Rouge: http://www.stateofthecoast.org/ This could not have been a more timely meeting of scientists from all disciplines concerned with the health of the Louisiana coastal environment. If you scroll through the agenda you will see that the speakers represent regional experts from industry, government, and academia. Although organized long before the Deepwater Horizon explosion, during the coffee breaks all conversations ultimately drifted toward the obvious, and most speakers (including myself) slipped a spill-related slide or two into their presentations. I talked to biologists, ecologists, engineers, and geologists, in this venue we were able to exchange opinions, integrate knowledge and, of course, spread rumors. Will it provide sediment to a sand-starved littoral system? Yes. Will it protect nesting birds on the beach? Maybe. However, not a single person I talked to supported the opinion that the berm could achieve it’s proposed function: to prevent oil from reaching the marsh. The conference was concluded with a special plenary session about the oil spill. The session was recorded on video and I hope it will be posted online soon, as it provides succinct opinions by a panel of experts who know what they are talking about. Irving Mendelssohn (LSU) introduced an excellent video that describes potential biological impact of the spill:
http://www.youtube.com/watch?v=syGM13egoc0

Regarding the berm. Greg Stone (LSU) suggested a limited berm, with the closing of smaller tidal channels along the southern shoreline. I am concerned this might somehow extend the low-water exposure of the marsh-plant root-system to oil, Dr. Mendelssohn explained such exposure would result in plant mortality and land-loss. I talked to Dr. Stone about this after the session, he did not think the tidal exchange would be affected. He did subscribe to the general concern that blocking tidal flow in some tidal inlets will increase scour in others. Already I hear they are placing berms in Quatre Bayou Pass and Pass Abel. To maintain equilibrium of the tidal prism, this may widen and deepen Caminada Pass, ironically one of a very small number of major inlets in Louisiana that actually have homes along their shore. But, as panel member Edward Overton (LSU) put it during the plenary session: the oil-spill mitigation plan isn’t about good results versus bad results, it’s about terrible results versus bad results. No matter what mediation action is taken there will be negative consequence, hopefully the incident team and state managers will listen to scientific opinion and at least minimalize the inevitable impact. Not sure how much rational thought is making it to the implementation stage as there is definitely a sense of urgency in the air. The prevailing statement from the state government is that the time for studies and questions is over and it is time for action. Ironically, one of the panel members said, and I know this doesn’t help the situation but I have to repeat it: “if we had been properly maintaining our barrier island and marsh environment all along, this would not be as big of a problem”.

The conference was covered by Louisiana's Daily Comet, but the website Jim links to is worth a visit and I sincerely hope that session video will be posted on line. And note that Jim also pointed me to a useful blog that is worth following, the lacoastpost that tracks "all things coastal." The blog was started by Len Bahr who had been the director of Louisiana's Applied Coastal Science Program, and I particularly enjoyed his post titled  "Like sand through the hour glass, so are the dunes of our lies."

It should be appreciated that the USGS has probably been instrumental in diverting the original berm plan, to dredge a linear trench one-mile offshore for borrow material, toward targeting point sources instead and stressing the importance of avoiding dredging within the footprint of pre-Katrina island shorelines. This is paramount because enough is simply not known about how natural recovery from this 100-year event will proceed, and upsetting any re-equilibrium process could be detrimental in the long-term. Will these suggestions be incorporated into the dredging plan? This will not become clear until the dredgers break ground.

Meanwhile, the ground is being broken, dredgers are being deployed and " Dredging sediment for the state’s new sand berms should begin Sunday at the north end of Chandeleur Island," Gov. Bobby Jindal said Friday afternoon....Although work on the sand berms will start this weekend, the state has asked the corps for permission to dredge closer to the islands than originally planned in the short term if the state promises to replace the underwater sand within three weeks, the governor said.

Associated with this activity have been a number of stunning pronouncements, of which I shall select a couple:

"There's always upsides and downsides," said Coast Guard Lt. Cmdr. Dan Somma. "This sand naturally moves, because these are natural barrier islands. So during a hurricane, these sands would be moving naturally anyway. This process just speeds that along."

and, again from the Daily Comet:

Lawmakers have been briefed about the berm project during the regular session, which ends June 21, but few have shown any interest in the scientific concerns being raised.

Asked about them this week, state Rep. Jerry Gisclair, D-Larose, delivered his answer with a growl and tone of resentment matched by only by his colleagues in the Houma-Thibodaux delegation

“I have no concerns,” Gisclair said, his voice increasing in volume. “I want to see as many berms as possible. We can always blow the sand away. There’s just no sense of urgency on this oil spill.”

"We can always blow the sand away" - what in heavens' name is he talking about?

So, to return to a more rational voice, I've quoted extensively from Rob Young, Coastal geologist at Western Carolina University, whose commentary has at least reached a number of media outlets. A recent piece from Newsweek that begins "Scientists are such spoilsports, always insisting on gathering data on the likely effects of a strategy before implementing it" continues:

Before this, Jindal was known to scientists as the governor who in 2008 signed a law allowing the state's public schools to teach creationism (excuse me! "intelligent design") in their classrooms. The difficulty he has distinguishing science from faith reared its ugly head again when he cast about for a way to hold back BP's oil. Emissaries from Jindal's office have made regular pilgrimages to the Netherlands to consult with engineers about protecting the state's coasts from the next Katrina. Van Oord, a marine engineering and dredging company that is constructing the artificial Palm Islands for Dubai, proposed building what amounts to artificial sandbars. "If you ask a Dutch company that builds artificial islands in Dubai how to protect marshlands and barrier islands," says coastal geologist Rob Young of Western Carolina University, "of course they'll say, 'Let's make an offshore island!—and shall we put a palm tree on it for you?' "

And from a recent interview for NPR:

Young says he worries these plans are being made without enough scientific oversight.

"We need a better way to involve scientists and engineers in formulating these ideas and doing very, very rapid review of them once they've been proposed," he says. "The oil spill is going to be with us for years, not days. So it seems like spending a little time right now to put together a process for better but more rapid scientific review would be worth the trouble."

Despite his concerns, Young says he does empathize with the governor's urgency.

"I hate being viewed as someone who might be attempting to obstruct the action to project and save that coast," he says. "I'm just heartbroken and furious about the impacts of this particular spill. I mean, every morning when I wake up, I'm not sure whether to call somebody in anger or to cry or to throw up. But doing something just to be looking like you're doing something is not the right thing to do."

I'll close (almost) with an extract from a New York Times  op-ed piece by Young titled "A Sand Trap in the Gulf":

We should also remember that while there is no magic bullet for the spill, that doesn’t mean we should just try everything and see what sticks. It would be more prudent to continue fighting with methods like modified booms (as is being suggested for Alabama’s Perdido Pass) and collection until effective long-term solutions can be fully vetted by engineers and scientists specializing in coastal environments.

The BP spill will be with us not for weeks or months, but for years. If we want to do our best to stop the oil from hurting critical habitats, then it’s worth taking a little time to get it right.

All I can say is "hear hear"!

And, finally, speaking of effective solutions, here's a really interesting idea from another scientist who knows what he's talking about, G.Paul Kemp, a former marine science professor at Louisiana State University who works now with the National Audubon Society's coastal initiative: unleashing the Mississippi to flush oil from the delta.

 

Weekend break: a vintage medical sandglass

My latest acquisition to add to my eclectic collection of things arenaceous. I found this essentially by accident and felt compelled to have it. It's a beautiful object in its own right, and historically fascinating. Here's an extract from the description:

Vintage Medical  1/4 Minute British Pulse Glass Timer Victorian Circa 1880-1900

This is an original quality vintage 1/4 Minute pulse timer as used by nurses and doctors, circa 1880-1900 to check patients' pulse rates, prior to the invention of wind-up 'watch' type timers. The timer is a sand filled glass tube similar to a egg timer encased within a nickel plated brass casing with a loop at the top for attaching to the uniform and hand cut windows to both sides to aid viewing of the sand. The glass tube can be removed from the case by unscrewing the looped end fully, and gently pulling the glass from within. The timer is stamped to one side with 1/4 Min, and then to the other side BRITISH MAKE. The quality of this time shines through when you look at the glass tube, which is etched to both ends with the details 3F/-, which is a variance mark.

It's about 6.5 cms long and and accurate to the second - I checked.

Berms: a sobering lesson from Dauphin Island

 

The more I poke around at the continuing and controversial (to some) issue of berm-building, the more mind-boggling and stupefying it becomes.

For example, they're building berms right now on Dauphin Island, a barrier system off the coast of Alabama. Now Dauphin Island happens to be the dramatic example of barrier island dynamics that I used in my book for the chapter on coasts; here's an illustration from the USGS that I adapted as showing the relentless redistribution of sand, the shape-shifting nature of barrier islands:

 

Three images over a very short period of time. The arrows locate the same points in each image and the period covers the ravages of Hurricanes Ivan (2004) and, of course, Katrina in 2005 - not to mention the more normal processes of tides, waves, and the regular lesser storms. At the lower left of the bottom image is an oil platform. In an earlier post, I referenced imagery that illustrates the effects of " normal, natural, wear and tear of wave and weather" - the emphasis in commentary on the current plans for "The Great Wall of Louisiana" may be on the likelihood of berms disappearing completely with the first tropical storm, but the fact is that everyday wear and tear will demolish them without the need for major weather events. And the history of berm-building on Dauphin Island is a case study - one that, should anyone be interested, is a sobering lesson. This is documented in a 2007 paper in the Journal of Coastal Research by Carl Froede of the Environmental Protection Agency. The paper is titled "Elevated Waves Erode the Western End of the Recently Completed Sand Berm on Dauphin Island, Alabama," and here's an extract (edited slightly in the interest of simplicity - references removed - and the emphasis is mine):

Dauphin Island is a microtidal barrier island in the northern Gulf of Mexico located approximately 8.0 km offshore from southwestern Alabama (U.S.A.). Passing hurricanes have historically brought about changes to the island since European settlement began in 1699. Hurricane Katrina struck the island on August 29, 2005, as a Category 2 hurricane and produced considerable geomorphic changes across the island. The low-lying residential western portion of Dauphin Island East was completely overwashed during the course of the storm. As a result, a significant portion of the Gulf-facing beach was removed and numerous island-cutting channels were formed . The damage to this portion of Dauphin Island required immediate action. Following the infilling of the numerous island-cutting channels and the restoration of the road, steps were then undertaken to create a 2.5 m high sand berm along the western 6.4 km of Gulf shoreline to protect this section of the island from future washover events.

Construction on the island’s largest sand berm project (to date) began on January 29, 2007, and was completed within four months.The berm was initiated on the western end of the island and proceeded toward the east. Sand was collected from the washover fans on the Mississippi Sound side of the island and pumped across the island, where it was reworked into a sand berm along the existing shoreline. No effort was made to create any beach zone in front of the sand berm. The berm serves as a temporary measure intended to provide time to determine a possible long-term solution for this portion of the island.

Erosion problems developed along the sand berm even before it was completed. Elevated waves in middle to late March began to erode sections along the western end, and corrective actions were undertaken to adjust the grade of the berm experiencing the excessive erosion. These actions proved futile, and several breaches to the berm developed in April. Waves continue to erode many sections of the sand berm along its western end.

The images at the head of this post are from this paper, and the captions are (left) "Elevated waves eroded away the former berm across this portion of the island. This is the largest of the breaches in the sand berm, extending approximately 92 m in length" and (right) "Significant erosion continues to occur along the western portion of the sand berm." The Images were taken July 27, 2007.

This was an interim report. By the time Hurricane Gustav had passed through in August 2008, the 10 foot high berm, built at a cost of $3.6 million of Federal Funds, had vanished. This was the third time since Hurricane Georges in 1998 that Dauphin Island's manmade "protective berms" had been wiped out by hurricanes - never mind the daily wear and tear. The erosional and depositional effects of Gustav are dramatically illustrated in a USGS report showing pre- and post-storm topography:

 

 Dauphin Island, AL, 2008. Three-dimensional view of changes in island elevation between June 2007 and September 8, 2008. Red indicates areas of elevation loss (erosion) and green indicates areas of elevation gain (accretion). The view is looking west along the island with the Gulf of Mexico to left. The emergency berm built after Hurricane Katrina was completely eroded, and sand was deposited inland. Overwash along the road was cleared prior to the lidar flight. Piles of cleared sand are seen in green along the north side of the road. The patches of red and green on the houses are an artifact of data processing. Large green rectangles on the ground are locations of houses built since Hurricane Katrina.

These berms were not, of course, "restoration projects" by any stretch of the imagination - they were built to attempt to protect property. Approximately 300 homes were destroyed by Ivan and Katrina and many of the lots are now in the ocean. The population of Dauphin Island? 1300 permanent residents - although that's stretching the definition of "permanent." Even back in 2006, the protective berms were controversial:

“Everybody is waiting on the berm,” said Jan Blackmon of Richmond, TX, whose vacation home was swept away by Katrina.

For others, such a project is a foolish waste of money, most of it from taxpayers, in a futile attempt to resist the wrath of nature. Even more, Dauphin Island is for them a symbol of the excessive financial aid that benefits mostly privileged folks whose vulnerable coastal property has been hit repeatedly by storms.

Opponents said such spending won’t outsmart Mother Nature. Steve Jones, a coastal geologist of the Geological Survey of Alabama, wouldn’t build a home there.

While the eastern end of the island is stable because of dunes, trees and other natural protections, the slender western end is little more than a big sand bar cut into plots for residential development.

“It’s almost like a dog wagging its tail it moves so much,” said Jones. Approximately all the homes that were destroyed or severely damaged were on that active, constantly moving western end.

In the face of all this, and presumably under a completely different regulatory system from that in Louisiana  (where there have been loud complaints about delays - or perhaps it's simply that it's not being paid for by BP), they're building berms on Dauphin Island again, and have been for several weeks (photo AFP):

 

But the story doesn't end here. Since Katrina, Dauphin Island has in fact been two islands, separated by a wide channel scoured out by the hurricane and maintained by normal coastal processes ever since. Note Google Earth images from 2000 and 2008 - and note the current and wave dynamics in the channel:

 

There is now a plan to block this entire channel. And what a plan! Here it is:

 

No, I'm not kidding. As reported on the Science Insider webpage published by the American Association for the Advancement of Science (I would have thought a reliable source), under the title "Emergency Oil Spill Response—How Sketchy Is It?":

It could be one of the sloppiest engineering plans the U.S. Army Corps of Engineers (USACE) has ever seen—a hand-drawn plan illustrating how engineers would fill in a channel in Dauphin Island to prevent oil from reaching sensitive wetlands. The corps posted the permit application and asked for comment from agencies and public in just a few hours.

The project could be a good idea, scientists say, but it's hard to tell given the rough plans, and it's equally hard to have confidence in such a quick evaluation. "It's very symptomatic of this whole episode," says George Crozier of the Dauphin Island Sea Lab, referring to the Deepwater Horizon leak. "There is a lot of panic and uncertainty."

I've quoted the informed views of coastal geologist Robert Young on the berms issue in previous posts. Here's what he had to say about this:

Coastal geologist Robert Young of Western Carolina University in Cullowhee, North Carolina, says he was stunned by the short deadline. Young, who says he often comments on permit applications for coastal engineering projects, only came across the proposal later that evening. "This makes me wonder how many of these emergency permits are out there that I haven't seen."

Young and other experts were also flabbergasted by the rough plans. "They're done by hand on a piece of notebook paper. I've never seen anything like this in my life." Young says it's difficult to tell from the drawings exactly what the consequences of filling the channel might be. And then there's the vague note on the map indicating "various buried pipelines."

There's a lot more in the Science Insider piece in terms of where the sketch came from and who is involved - I can't bring myself to repeat it here, but please, feel free.

What I still can't see are any signs of joined up thinking - not just on the berms issue, but on the response to dealing with the spill and mitigating this disaster (and I'm not talking about attempts to cap the well, but the management of the consequences). Back to Rob Young again:

The BP oil spill will be with us for years, not days. In order to move forward in a sensible way, the administration should set up a scientific review panel to vet all proposals for large-scale coastal engineering in response to the spill. The panel should include experts from science agencies like the U.S. Geological Survey and the National Oceanic and Atmospheric Administration, as well as leading academics. The review panel should still be charged with responding very quickly to permit applications, but the public needs to have a higher level of confidence that the best science is being brought to bear on this problem. At the moment, that is simply not the case.

There's no sign of such a panel, an emergency task force of scientists. I go on the website of the Federal Office of Science and Technology Policy, the sicentific advisory group for the Whitehouse and Congress, and I read their mission statement:

OSTP's Mission

The mission of the Office of Science and Technology Policy is threefold; first, to provide the President and his senior staff with accurate, relevant, and timely scientific and technical advice on all matters of consequence; second, to ensure that the policies of the Executive Branch are informed by sound science; and third, to ensure that the scientific and technical work of the Executive Branch is properly coordinated so as to provide the greatest benefit to society.

"All matters of consequence" - if this isn't one of those, then I don't know what is, yet look at the website and you'd never know that there is a catastrophe in the Gulf of Mexico and that actions being taken run the clearly defined risk of precipitating a whole series of further "matters of consequence" for the wellbeing of the entire Gulf Coast.

I have to admit that I'm on the verge of giving up on this series of posts. It's not that I expect this blog to make any difference, but there is the continuing invisibility of the people who know what they're talking about but to whom nobody is listening; people whose efforts and expertise should be making a difference.

There's an escalating sense of despair and pointlessness - and my supply of blood pressure pills is limited.

[For further interest, there's a video report, "Dredge, baby, dredge" on the Time Magazine site; for more comprehensive coastal studies see "Continued redevelopment of the west end of Dauphin Island, Alabama—A policy review," a Special Paper from the Geological Society of America, and "National Assessment Of Shoreline Change: Part 1 Historical Shoreline Changes And Associated Coastal Land Loss Along The U.S. Gulf Of Mexico" by the USGS]

"The Great Wall of Louisiana" - required reading from the USGS

The saga continues, and, since it's important and the response to these ongoing posts has been, by the standards of this blog, considerable, I'll put all the other topics I was planning on writing about on hold for the moment. Like a prospector of old, I've been sifting through the sands of politics, punditry, publicity-seeking, and partisanship (does everything, a national disaster included, have to be a partisan issue?), seeking grains of gold. And by those grains, I mean informed and objective contributions from people who actually know what they are talking about (such as the pieces written by Dallon Weathers, referred to in previous posts). As the sand sifts metaphorically through my fingers, I've found a few grains of gold - and one nugget.

I've been tracking down the commentary of people like Gregory Stone, Professor of Oceanography and Coastal Sciences at Louisiana State University, Robert Dalrymple, Professor of Civil Engineering at Johns Hopkins University, and Paul Kemp, Director of the National Audubon Society’s Gulf Coast Initiative. Here are some quotes (sources listed below):

"The scientific community has been ostracized by the way the whole thing has been approached," said Gregory Stone...."I applaud the concept. My concern is that we are doing this haphazardly and it comes around and bites us and that has longer term implications," said Stone, who said sandbags and protective booms would make a better stopgap measure.

.............................................................................

"There are two major problems: where we would find the sand? How would we mobilize in time to make this effective?" said Robert Dalrymple.... But completing comparable projects in Maryland, Delaware and New Jersey has taken years and required many millions of cubic feet of sand, Dalrymple said. Given the complexity of the Delta marshlands, oil would likely get in anyway.

.............................................................................

"There’s no real way of keeping it (oil) out of the marshes using any kind of barrier except very locally in quiescent bayous," said Paul Kemp...."There is a lot of consternation and part of it is that we know so little about this plan and what we do know shows a lack of thought.

And then I found it. I'd seen references to input from Jack Kindinger, Director of the U.S. Geological Survey's Coastal and Marine Science Center in St. Petersburg, Florida:

"If they don't accommodate the tidal volumes, that water's going to come out somewhere," said Jack Kindinger.... "When you start changing the regime, the water's going to find the weakest spots." Kindinger added, however, that moving sand is key to any future for barrier islands off the coast. "Anytime you move sand into a sand-starved system, you're helping it."

I had been wondering where the USGS was in all this - their specially set-up website, http://www.usgs.gov/deepwater_horizon/, is a great source of collated and critical information, but nothing had appeared in terms of a specific Survey response to the berm proposal. Until now - or, to be precise, June 2. Tracking Kindinger's results on my web search, I eventually found reference to Open-File Report 2010-1108, "Effects of Building a Sand Barrier Berm to Mitigate the Effects of the Deepwater Horizon Oil Spill on Louisiana Marshes."

I follow the USGS Newsroom, daily expecting something like this, but nothing shows up. Go to their Deepwater Horizon site, linked above, and scroll down to "publications," and now, there it is. I've seen nothing in the media about a contribution that was published almost a week ago and should be widely publicized and headlined, given, in the words of the report, "the enormity of this project" - but then it's just a scientific contribution to policy......

I thoroughly recommend reading this report - it's not long, it's objective and, as is appropriate for a major Government Agency, does not condemn the project out of hand. But I'll copy here the concluding sections:

Issues Related to the Sand Berm
Numerous considerations have been identified by the USGS and collaborators that must be addressed when considering an alteration of the shoreface configuration:

• In light of the enormity of this project, it is critically important that the sand berm be constructed in a timely manner to ensure success. The most efficient means of achieving success will rely on prioritizing segments to be built in terms of potential ecological impacts.

• A second factor in prioritization is difficulty of construction. For example, after the recent hurricanes, barrier islands no longer form a continuous chain from the northern tip of the Chandeleur Islands to Breton Island near the bird’s foot delta, a distance of approximately 100 km. Even prior to Hurricane Katrina, approximately 50 percent of this reach was open water, which the berm is intended to span. Here, the berm will be particularly vulnerable to destruction during storm surges and waves. Building the berm in this open, deep water will require more mined sand to build the structure 2 m above sea level as designed.

• Studies of the Chandeleur Islands have shown that exceptionally large coastal changes can occur during storms (Sallenger and others, 2009; fig. 4). During even relatively low-intensity storms, it is likely that the berm material will be overtopped by waves and sand driven onto the island and possibly into the back bay (for example, see the overwash of Hurricane Lili (category 1) during 2002 (fig. 5) or Hurricane Ike (category 2) in 2008. Such overwash during storms could transport oil and sediment across the island and into the back bays toward the mainland.

• East and west of the birdfoot, the reduction of inlets during berm construction will reduce the capacity of the inlets to handle the amounts of water exchanged by tides. Flow velocities will be rapid, and changes to the berm and islands will result. Salinity gradients and turbidity concentrations within the back-barrier bays will be altered, thus affecting the present ecosystem.

• With the profoundly fast time line needed to provide oil-spill protection, care must be taken to provide (1) sufficient oversight and (2) information regarding the adequacy of the borrow sites, the positions of pipelines and other obstructions that, if damaged, could exacerbate the ongoing spill, the effects on marine habitats, and the possibility that storms may remove the berm so quickly that it does not serve its intended purpose.

• The sand berm is intended to be sacrificial. Although redistributing material within the system as it degrades will be beneficial in the long term, this project should not be confused with and will not have the longevity of a true barrier-island restoration.

• Sand resources along the Louisiana coastline are scarce. The excavation of this material for use in building an emergency berm may compromise future coastal restoration efforts by reducing the sand resources. Efficient and well-managed extraction and placement of these resources will be necessary.

• Under these emergency conditions with no time for adequate environmental assessment, long-term issues of concern include (1) entrainment of oil in the sediment plume created during dredging operations, (2) sequestration of the oil in sediments only to be released years later, and (3) anoxic conditions in the borrow areas. Monitoring will allow characterization of these potential conditions.

Long-Term Monitoring
Finally, long-term monitoring of the berm is recommended to determine its performance and possible impacts and benefits to the surrounding environment. Repeated surveys to update bathymetry, topography, seabed characteristics, and seabed images along with sediment sampling should be done to document changes through time. These observations and analyses will provide data needed to identify movement of oil
and oil degradation through the system, determine impacts, and identify the processes involved. For example, monitoring changes in barrier topography and bathymetry along with analyses of sediment cores and oil-residue changes will show linkages between oil mobilization and sedimentary processes. Monitoring turbidity and salinity within the back-barrier environment either remotely or in situ using boat-mounted
sensors will provide proxy information on estuarine health.

Figures 4 and 5 referred to are reproduced here:

 

At this point, all we know is that the contract for the berms project has been awarded (presumably through a thoughtful tendering process) to Baton Rouge-based engineering company, The Shaw Group, who announced this a few days ago:

BATON ROUGE, La., Jun 04, 2010 (BUSINESS WIRE) --The Shaw Group Inc. (NYSE: SHAW) today announced it has been awarded a contract by the state of Louisiana's Office of Coastal Protection and Restoration for overall project management and construction of sand berms in response to the Deepwater Horizon oil spill.

Shaw will assist the state with permit compliance and monitoring activities in addition to providing personnel, materials and equipment to build these sand berms. Construction of the berms in accordance with the emergency permit issued to the state will require mobilization, front-end planning, material testing and analysis, dredging and alignment surveys, as well as coordination with state and federal agencies.

One must assume that the recommendations set out by the USGS were included in the stipulations of the contract.

 

[Professor Stone can be heard on the website of Baton Rouge TV station, WBRZ-TV, under the heading "LSU Professor: Sand berms good idea, but not now" broadcast on the 27th May. Other sources: http://www.sce.lsu.edu/; http://www.latimes.com/news/nationworld/nation/la-na-oil-spill-berms-20100606,0,7544795.story; http://themoderatevoice.com/75371/the-great-wall-of-louisiana-hoax/; http://mediamatters.org/research/201005270020]

Weekend break - other sand in the news

Put the words "Louisiana sand berms" (or even simply "sand") into Google news search, and it's apparent that the rhetoric around what is now being termed "The Great Wall of Louisiana" continues unabated (see, for example, The Seattle Times and the LA Times). But it's time for a break from this saga, a little light relief.

As the opening of the Football World Cup rapidly approaches (England's first game is against the US - the latter, of course, playing soccer rather than football), celebration in South Africa takes many forms. Including a collection of sand sculptures of the different stadiums hosting the games - above left, the brand new stadium in Durban.

And, in Moscow, six men have now been locked in a sealed complex of containers for 18 months (at least, that's the plan) in order to simulate a manned mission to Mars. One of the many facilities within the complex is a "Martian surface simulator" - otherwise known as a glorified sand box.

Oh, and please note that I now added, long overdue, a widget on the sidebar of this blog to link posts, should readers wish, directly to networking and bookmarking sites.

[Sand sculptures from Jon Saintz, originally published in The Observer; Mars experiment image from the project website, further information from many sources, for example the BBC news]