Thin Blue Line

Sea Level Rise and the New Intertidal City

Dark Mountain: Issue 6, our brand new collection of uncivilised writing and art, is now available. Over the next few weeks, we're going to share a little of what you'll find in its pages. Today, we bring you Robert Alcock's response to our call for 'the rising of the waters'. We hope you enjoy.
is an eco-designer, builder, writer, father, Zen animist, and activist. He and his partner created Abrazo House ecological learning centre in northern Spain. If he's not there, he can usually be found in Edinburgh, where he makes mischief with Extinction Rebellion. He has been writing for Dark Mountain since 2011 and has been published in issues 3, 6, 10, 15 and 23.  

The ice age is coming, the sun’s zooming in
Meltdown expected, the wheat is growing thin
Engines stop running, but I have no fear
ʻCos London is drowning and I live by the river1

The photo is of an intervention (graffiti? street art? I don’t really know what to call it) that I began in 2011, in the post-industrial waterfront district of Bilbao where I used to live. It consists of a thin blue line, at a height of roughly a metre above the high-tide mark, painted over everything in its path – walls, gates, lamp-posts, trees…

I say ʻbeganʼ because I imagined the line continuing downriver to the sea, then spreading to other sea-level cities around the globe – but I ran out of paint after about two hundred metres, which seemed enough to be going on with. (If this essay inspires you to continue the project in your own city, be my guest.)

The point, of course, was to depict the imperceptible yet inexorable trend of sea level rise: to place it in the public domain, visible to the naked eye. The height of the line is somewhat arbitrary: one metre is a nice round figure, and a convenient height to paint if you’re standing on a road that’s basically at sea level. Regardless of how fast the seas may rise, they won’t stop rising in the foreseeable future, so the question is not whether sea level will reach the blue line, but when.2 2100? Sooner? Later? Nobody knows. For the record – given the exponential growth of bad news about the climate – I’m guessing significantly sooner, like around 2075. The main unknown factor is the rate at which the Greenland and Antarctica ice-caps will melt. The ice age is coming, the sun’s zooming in / Meltdown expected…

Even in 2011, though, it was still possible to talk about halting sea level rise, and to naively imagine that small acts of civil disobedience could tip the balance. In hindsight, this was probably an illusion – especially for a faint-hearted activist like me, nervous of exercising my right to free speech on other people’s walls, even in an area of abandoned factories and vacant lots already swamped in graffiti. Just imagine if I had painted the line where someone might actually notice it – on the fronts of my neighboursʼ houses, say, or the titanium facade of the Guggenheim museum, also located at sea level, a few kilometres upriver!

As it was, I was half expecting to be told off by some guardian of public decency – which is just what happened: my downstairs neighbour Luis strolled by and caught me in the act. He snorted and said something along the lines of, ʻIsn’t it bad enough for kids from outside to come here and mess the place up, but you have to go and make it worse!ʼ I tried to explain myself, but he looked at me uncomprehendingly and walked on.

Obviously, like most people, Luis concerns himself almost solely with local issues – including what he sees as the defacing of the area where he’s lived for forty years. He’s much less worried by the rising seas than by the rising tide of ʻvandalismʼ in his neighbourhood. I suspect he knows, and cares, as much about the melting of the Greenland ice caps as a typical Inuit does about the league performance of Athletic Bilbao. So much for influencing public opinion.

But when I stepped back and looked at my work, I realised that, as often happens, the unintended effects were more interesting than the conscious intention. The blue line wasn’t neutral, merely calling attention to a trend. It had an ambivalent, slightly menacing feel to it. I was reminded of the condemned houses in post-Katrina New Orleans, spray-painted with a code to indicate their hazardous contents (X dead bodies and Y fridges full of rotten food), and the movement to resist their demolition and the relocation of local communities.

A touchy subject. Since 2004 the residents of my old neighbourhood had successfully defended their (our) homes against the bulldozers, and helped paralyse – for almost a decade – plans to build a mini-Manhattan of luxury skyscrapers, designed by superstar architect Zaha Hadid. At the time of writing, Zaha’s Master Plan is allegedly still going ahead, albeit far more slowly and in a modified form, with more ʻsustainabilityʼ (i.e. green space, trams and car-free zones) included. But meanwhile, a community of upstarts – theatre and circus folk, artists and craftspeople of all kinds, ukelele players, flea marketeers, urban gardeners, and so on – is thriving among the disused factories and warehouses.3

So what if ʻmeanwhileʼ became a permanent condition? What if everyone knew this place was going to be underwater some day, and everything was done for ʻthe momentʼ, with full awareness of its (and our own) mortality? Perhaps the thin blue line should be seen not as threatening a status quo, but as defining – and defending – a new territory. A liminal zone, a wild frontier, a floating world. The Free State of Meanwhile. The Intertidal City.

I am not talking about planned retreat, mitigation or adaptation. Those concepts imply the continuance of business-as-usual by whatever means necessary. While government and industry build costly – and ultimately futile – sea defences, shift to higher ground, or simply cut their losses and flee, the intertidal city will play host to a different project: a cultural transformation of the relationship between human beings and the sea.


 Full fathom five thy father lies
Of his bones are coral made
Those are pearls that were his eyes
Nothing of him that doth fade
But doth suffer a sea-change
Into something rich and strange.
Sea-nymphs hourly ring his knell…4

Like other wild places – forests, mountains, wetlands – to the civilised mind the sea has always represented the unconscious, the uncontrolled, the other. But whereas civilisation has always sought to tame (i.e. to destroy) other wild places, its relationship with the sea is more intimate and more complex. In fact, the sea permeates the very heart of civilisation, bearing an immense material and cultural legacy.

Sea levels have actually been rising ever since the last ice age – rapidly from about fifteen thousand to seven thousand years ago, including some catastrophic events (hence the universal legend of the great flood), but much more slowly thereafter.5 This stabilisation, doubtless, was a factor in the rise of civilisation. Cities have always been synonymous with the growth of trade – and of war, the flip-side of the same coin, delivering different merchandise via the same logistical means. And trade has always been predominantly seaborne. The history of the West, especially, is dominated by one maritime city after another – Athens, Rome, London, New York – with continental cities mostly playing second fiddle. Even today, 90% of goods are transported by ship.6 Amazingly, an estimated one hundred and forty-five million people – one human being in fifty! – live below the thin blue line, within a metre of sea level.7 Put it this way: if I was Gaia and I wanted to bring down civilisation while minimising damage to ecosystems, rapid sea level rise would be my weapon of choice.

Eighty percent of these people live in Asia, 10% in Europe.So many people clinging like limpets to such a narrow strip of territory. Narrow, but exceedingly long: stretching from Amsterdam to Alexandria, Bangkok to Bilbao, Cardiff to Cape Town, Mumbai to Miami, Rio to Riga, Seattle to Shanghai, Wellington to Washington… Perhaps it’s the subconscious tug of tide and brine, reminding us of our origins in the sea, in the womb.

I know I’ve felt this. After growing up in the English Midlands, far from the coast, I spent three years doing ecology fieldwork on rocky shores, working during spring tides, when the lower shore is uncovered: living with the offset rhythms of the moon, one week out of every fortnight, an hour later every day. I continued the work even after I realised I wasn’t cut out for an academic career: while I found being on the shore and observing its creatures thrilling, reducing their diversity to data bored and disturbed me, and the process of generating and testing simplistic hypotheses seemed sterile by comparison with the richness of life in a rock pool.

I suppose this makes me a Romantic, returning to wild nature for inspiration, reacting against the dominion of the rational mind (I had already switched subjects from physics to ecology). The whole idea of going to the seaside, in fact, can be seen as arising from the nineteenth-century Romantic movement, combined with the growth in mobility of the urban masses.

Which brings us, inevitably, to Venice: the city married to the sea, which gave birth to capitalism and the modern era. Venice was a destination for Romantic tourists before either the concept of tourism or the Romantic movement existed.8 It is particularly relevant to note that the world’s first beach resort proper – now replicated along thousands of kilometres of coastline worldwide – was the Lido of Venice.

And now, of course, it is the world’s most famous intertidal city, poster child for sea level rise. In point of fact the flooding of Venice, to date, has more to do with subsiding land than rising seas – it’s ahead of the curve again. But at any rate it makes a beautiful modern-day Atlantis, and a model for the intertidal cities of the future. All the more reason to go there now, before it sinks beneath the waves forever, before air miles are subject to rationing or peak oil puts an end to budget flights.

At least, that was my excuse for agreeing to fly there for a family holiday, in May 2013. (Unfortunately, I have read and thought enough about climate change to make me fret pointlessly over choices like this. Any sensible person would take the holiday and not lose any sleep over it. Rationally, I know that my individual decisions as a consumer can hardly make a difference to the global climate. Collective decisions are another matter, if it were possible to make these on a global scale. But I still felt personally responsible for the fact that, a couple of days before we left, atmospheric CO2 concentrations hit 400 ppm for the first time in millennia.)

Of course Venice happens to be a mass tourist destination, with a wealth of cultural treasures accumulated during centuries of fleecing the known world. (Just one milestone in a long and sordid history: Venetian bankers crashed the European economy by manipulating the exchange rate between gold and silver – in 1346.9)

But more to the point, it’s also a living city in an intimate embrace with the sea. I overheard an American woman on the Rialto say it was ʻjust like Disney, only weirderʼ; I suppose that was her only other experience of a human-scale, car-free built environment.

The best part of our trip was acqua alta – flooding – which isn’t supposed to happen in May, but it did. We had to wade to get in or out of our street, which delighted at least two of my travelling companions (aged nine and seven). The locals wore wellies, I went barefoot. Social barriers broke down: as we chatted to two Venetian gentlemen on the Fondamento dei Mori, a green crab scuttled by on the flooded pavement; one of them caught it and showed it to a couple of passing schoolboys. For a few hours, an unmistakeable atmosphere of carnival reigned; then the waters subsided and life went on as before.

Venice certainly doesn’t seem to be suffering from a sense of doom and gloom due to its impending disappearance beneath the Adriatic. One resident told me that he much prefers it in the winter, when there is more acqua alta but fewer tourists. Water, it seems, the Venetians can handle. The main threats to the city – as far as I could judge during one short visit – seem to come from inundations of money: the super-rich buying up property that then lies empty; giant luxury cruise ships damaging the lagoon; and MOSE, a corrupt sea-defence project apparently designed to divert funds, not floodwaters.10

Which seems to make a general point nicely. Which is more dangerous: the forces of nature unleashed by climate change – or the civilisation that caused them to be unleashed in the first place? It’s true that extreme weather and violent flooding are serious hazards – but they are much worse when exacerbated by deforestation, building on flood plains, and other unsustainable land-use practices driven by corruption and greed.11

The worst damage, both to human cultures and the biosphere, comes from an out-of-control global economy. Sea level rise, rather than being a terrifying spectre from which to flee, or an excuse for siphoning public money into giant sea defences, can be embraced – as a liberating opportunity to bring wild nature into the heart of our dysfunctional cities.

Back in my old neighbourhood in Bilbao, flooding is slowly becoming a regular part of life. Last winter the main road was underwater several times during spring tides. Apart from flooded basements, the principal effect was that the area was closed to traffic, and people parked their cars elsewhere. For a while, it was wonderfully peaceful. Engines stop running, but I have no fear / ʻCos London is drowning and I live by the river.

Welcome to the intertidal city. Don’t forget your wellies.

1 The Clash. (1979) London Calling
2 The IPCC predicts 30-95cm by 2100, while the US National Research Council says 56-200 cm. In May 2014 a new study concluded that the melting of the Amundsen sea sector of West Antarctica – adding a metre to global sea levels on its own, and leading to the collapse of the remainder of the West Antarctic ice sheet, causing another three to five metres of sea level rise – is now inevitable. The Amundsen sector is estimated to take a couple of centuries to disappear, but I have a strong suspicion those could melt into decades.
3 See ʻBeyond Zʼ in Dark Mountain 3.
4 Shakespeare, W. (1611) The Tempest
6 George, R. (2013) Ninety Percent of Everything, Metropolitan Books
7 Ahlenius, H. UNEP/GRID-Arendal, 2007
8 Rosalind to Jaques: ʻFarewell, Monsieur Traveller: look you lisp and wear strange suits, disable all the benefits of your own country … or I will scarce think you have swam in a gondola.ʼ Shakespeare, W. As You Like It, 1599
9 Piers Tremlett. (2012) The Spirit of Venice
10 At the time of writing, the mayor of Venice is facing corruption charges related to the MOSE.
11 Monbiot, G. (2014) ʻDrowning in Moneyʼ, The Guardian, January 13th, 2014.

You’ll find more where this came from in our latest book. 

  1. Thank you for this lyrical piece, Robert. I’m particularly drawn toward your visualizable “a liberating opportunity to bring wild nature into the heart of our dysfunctional cities.” Hear, hear! Embedding within the disruption and chaos, we’ll no doubt discover many things of beauty and grace.

    1. Thanks, Seth! Yes indeed. Discover—and create. I’m hoping that this essay will spark a discussion about the kind of creative interventions that can happen in the new intertidal city (and by extension, in new liminal places created by other forms of disturbance), and that people will actually go out and make/do stuff as a result—perhaps starting off with a thin blue line as a declaration of freed space, and a kickstarter for other, better, more detailed actions.

      It’s a territory that we can take back with the simple act of declaring: “In the long run, this area belongs to wild nature. And as of now, to its free, creative spirit.”

      As they say, the best way to predict the future is to invent it.


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