Through The Sandglass

Reports from the Solway Firth (2): Guest Writer and a Submerged Forest

 

My kind hosts for the Café Scientifique event were Ann Lackie and her husband, John. They had set up the group originally and are to be commended for their devotion and the enthusiasm of the community that they have established. Ann (and the adolescent dog, Meg) were my companions for that exhilarating morning walk on the beach; the storms had scoured the sand away from an extraordinary sight - the submerged forest of the post-glacial Solway Firth. Ann is, amongst her many talents, a writer (see the end of this post), and a few years ago, under her alter ego, Ann Lingard, she had published an article on the forest for Cumbria Life magazine. It is with great pleasure that I can re-publish that piece here.

“NOW YOU SEE IT, NOW YOU DON’T”:

THE SOLWAY’S SUBMERGED FOREST

Ann Lingard

Leave your car at Beckfoot in the carpark amongst the dunes and walk down the track to the new wooden walkway onto the beach: stand there, on the pebbles, looking across the waters of the Firth towards the granite bulk of Criffel. If you are lucky, you may see low dark ‘cliffs’ on the shore, about 100 metres along your Criffel sight-line – a half-metre high, the patches of black are like shadows on the sharp edges of channels in the sand. Now walk down towards them, and the shadows resolve themselves into banks of peat. Poke them with your toe and feel how dense and sodden they are, smoothed by the friction of waves and sand. Walk on them and feel their sponginess. And gradually you’ll become aware that the dark organic mass is not only peat, but contains a horizontal tree-trunk, or even a stump that radiates roots. Wander around and you will find trunks and branches, single and entangled, embedded in the peat and sand; and erect stumps, 20-30 cms high, their tops flattened as though cut by a chainsaw. The wood is still fibrous, soft and dark; you can crumble it and tease it apart, as though it were any rotting log in a woodland. But the difference is that this woodland thrived about 8000 years ago.

However, the Solway’s tides and sands are capricious, and there will be many occasions when you go down to the shore and can find no sign of the ancient, submerged forest. One person I spoke to, who regularly surveys the Upper Solway’s shores, had never seen or even heard of the forest, and Brian Blake, whose excellent book The Solway Firth (published in 1955 and now, sadly, out of print) is illustrated by photographs taken by J. Allen Cash, notes that “Mr Cash went to Beckfoot ... the submerged forest was not visible and I regret to say the residents he inquired from had not even heard of it.” Fortunately for us, Val Corbett had no such problems as her beautiful pictures show.

Norman Hammond, of Solway Shark Watch, who also leads guided walks along the shore, told me that, “The best time to see the forests will link in with extreme high water springs and a few days with a severe gale-force blow from the North-West or better still the North-East. The North-East severe gale will move the south shore sand away on a massive scale and reveal  the forests - and usually a host of last war remains as well. It’s a case of dropping everything and getting down to the shore when conditions are okay.”

Well, I’m always happy to get down to the shore, even when conditions are not okay, and I have twice found the forest on Allonby Bay just South of the village, and once off North Lodge between Allonby and Dubmill Point. In the latter case, as at Beckfoot, there was no need to wait for the low Spring Tides – the forest was visible on the mid-shore, briefly exposed by the fierce northerly gales.

So how did a forest come to lie underneath the Firth? The obvious answer is “because the sea-level rose”, but of course the Solway has its own particular complicated version of events, which is explained beautifully simply at the Solway Discovery Centre at Silloth. The Centre is in the coverted red sandstone school, and the offices of the “Solway Area of Outstanding Natural Beauty” are at one end of the building in the former Headmaster’s House. Brian Irving, Manager of the Solway AONB, designed the exhibition and is almost evangelical in his enthusiasm for everything to do with the Solway. Our discussion ranges from topic to topic, with frequent interruptions to ferret through books, and to check the maps of the coast and the channels and the other nature reserves that are pinned to the walls. We also go through to the Centre to look at the models that Brian has commissioned to explain the protracted contest between the sea and the land.

During the last Ice Age, one huge glacier swept south and east to the Tyne from Scotland, meeting another glacier that ground its way North and West from the ‘Lake District’; as these melted, a large lake of glacial meltwater formed in the area bounded by the Scottish lowlands, the Pennines and the Fells. Then, as the ice retreated, so the shores of the lake were gradually colonised by plants and animals. What went on here was a reflection of everything else that was going on at that time in Britain, Brian tells me. “There was a wave of plant colonisation spreading North, a ‘tundra front’ moving North, with dwarf plants – dwarf willow and dwarf birch. The standard ecological colonisation.” I think about the tundra vegetation that I saw in Greenland a couple of years ago - juniper, and low flattened willow, dwarf birch and blaeberry blazing red and orange in the autumn, clinging to the sparse soil that was only inches above the permafrost - and try to imagine it spreading across from Silloth to Whitehaven and Dumfries. A fitting link with the Greenland Pinkfeet geese that now migrate here in the Winter.

Here on the Solway, around 8000 years ago, the air and soil started to grow warmer, and wind-blown tree seeds were able to survive and germinate. According to Brian, a pine forest gradually spread across our landscape, obliterating the tundra vegetation and lasting for a couple of thousand years. Mammoth, bison, giant deer and sabre-toothed cat grazed or hunted amongst the trees and on the grassland. Perhaps the landscape looked like that around Victoria Bridge just South of Rannoch Moor, where remnants of the ancient Caledonian pine forest still hang on? The forest there is sparse, the remaining trees scattered thinly amongst the rock and heather and pale tough grass, and beneath them lies an older forest, its ancient and bleached trunks and branches exposed where the peat has been cut to make a ditch. The “Solway” pines, though, began to disappear about 7000 years ago, succeeded by deciduous oak and alder and hazel. This new forest was low and dense with a thick understorey, Brian says: “You’d have found it almost impossible to walk through.” But perhaps you would not have wanted to, in any case, because this was a time when wild pigs were common. The forest would have been full of bird-song, you might have caught sight of elk or deer grazing, or even the now-extinct Auroch, Bos primigenus, a large ‘wild cow’.

We think of geological change in terms of blocks of time: 9000 years BP, 7000 years BP. But of course the process of change is gradual, and during this period the glaciers, here and elsewhere on Earth, were continuing to melt and pour their waters into the sea. The sea-level rose gradually and inexorably. It crept higher on the southern shore of the huge forested “Solway” basin, and the salt water oozed amongst the trees. Salt crystals blocked the water-channels within the tree-trunks so that the branches died of dehydration. “It was like beaver damage,” according to Brian Irving. “The twigs then the branches die and fall off, and you’re left with the spikes of stumps sticking up in the water.” Once the sea had made an entry it washed in further and invaded the immense freshwater lake and so the Solway estuary was born and broadened, fed by rivers of glacial meltwater, and flushed twice daily by the tide. The forest was drowned beneath the Firth, and should have been destroyed and lost forever. In theory, we should not even know it had been there.

The glaciers were melting. Imagine those huge masses of ice and boulders, weighing down and compressing the land; as they retreat, the pressure on the underlying land is released and the land rebounds and rises. This is what happened in the Solway basin, twice. The sea flooded in and drowned the land, but the land then rose; the still-rising sea encroached again but yet again the land rose. The evidence is there in the two “raised beaches” – the road from Allonby to Mawbray runs along the “Twenty-five Foot” or “Neanderthal” raised beach. But even this story is probably too simple. Frank Mawby of English Nature told me, “There would have been little islands at high water, and some quite dramatic drops in sea-level too. If you look at the marshes today, you can see little bits of raised beach all over the place.” In some places growing trees would have been overwhelmed by peat rather than by the sea. And Dennis Dickins, who runs Cumbria Environmental and Geological Services at Watch Hill, stressed the fluctuating climate and conditions: “There’d be a wet period when the woodland would retreat, then this would be followed by advantageous conditions for a couple of hundred years, so you get the trees re-invading. There was constant change.”

As for the drowned forest, each time the land rebounded some of the forest was lifted too. And with regard to that wet period, never complain that “it always rains in Cumbria”! About 7000 years ago, in the Atlantic Period of the Holocene, the climate was especially wet, the hills were almost permanently hidden in cloud and the rain poured down, day after day. Plants struggled to survive in the water-logged ground. These were perfect conditions for sphagnum moss to grow and accumulate water like a sponge. Reeds flourished but most of the other vegetation died and decayed and became compressed to form peat; the peat spread, blanketing the valley floors and creeping up the hillsides, burying the remains of the forest. On the raised beaches, the peaty “raised mires” formed. Hundreds of years passed, the mires or “Mosses” dried out, sedges grew, the moorland was colonised by woodland carr, silver birch and heather. The drowned forest was hidden deep down beneath the layers of peat and vegetation.

Peat is cold, oxygen-depleted, acidic, a good preservative. It preserved the “bog bodies” of Lindow, Tollund and Grauballe Man. Lindow Man (actually, only his upper half) was discovered in a Cheshire bog in 1984 and was probably a victim of a ritual sacrifice by ancient Celts. He died a three-fold death, finally being cast face-down into a peat-bog on Lindow Moss, a symbolic drowning. The two Danish peat-cutters who found Tollund Man in 1950 thought they had found the victim of a recent murder, his face was so “fresh” and well-preserved. This is characteristic of bog-bodies, their skin is “tanned” (a chemical process similar to turning hide into leather) and their internal organs and skeletal framework are thus often remarkably intact. Grauballe Man was found in a Danish bog in 1952, and is 2000 years old. Recently his body was analysed using computerised tomography (CT) scanning, a non-destructive technique by which X-rays generate 3D images. The computer is programmed to recognise different tissues according to their different densities in living patients, so it was a surprise to the researchers to find that the density corresponding to “skeleton” was absent from Grauballe man. The acidity of the peat had dissolved the calcium in the bones and tooth enamel, and the demineralised skeleton was more like rubber than bone. Even more surprising was the discovery that Grauballe Man had undergone some posthumous cosmetic surgery: his chubby cheeks had been padded out with plasticine by the museum’s curators in the 1950s!

Are there “bog bodies” buried in the Solway peats? Who knows? There were certainly humans living here 2000 years ago, but it is unlikely that humans hunted amongst the forests a few thousand years earlier. When I asked Frank if there were any “bog bodies” in the Mosses, he laughed and said, “No. But there was a cow found in Solway Moss!” Unfortunately it wasn't accompanied by any ”bog butter”, the 2000-year-old parcels of butter and lard, packed in wooden boxes or animal skins, that have been found buried in Scottish and Irish bogs. (There is a very interesting story of the "soap woman", whose fatty tissues were converted after death  ... but no, that takes us too far from the Solway.)

Returning to the Solway, Brian Irving told me that very little biological research has been carried out on the submerged forest. “The conditions were acidic so you wouldn’t get survival of calcareous shells, so there’s no evidence of land snails. Our information is based on things which survive the acidity – mainly plant remnants, pollen ...” Apparently an attempt was made about 25 years ago to radiocarbon-date a fragment of wood from the forest that lies just South of St Bees’, but I have been told there was some problem with the sampling technique; “8000 years old” is the date that’s quoted.

And I cannot pin down whether the submerged forest was oak or pine. Dennis Dickins thinks it was oak. Brian Irving thinks it was pine. Brian Blake writes in his book that “I was told that from some of the remains, and the prone trees are more than stumps, hazelnuts sometimes are found.” When I put the question to Frank Mawby, he said at once, “Oh – probably birch!” and then added, “I brought up a hazelnut once from seven metres of peat on Wedholme Flow.” And at Wedholme he has found a layer of marine sediment overlying the peat, further evidence of that dance between the sea and the land. I’m really surprised that opinion is so divided about the trees. Would there be any DNA remaining in preserved cells deep within the wood that would make the identification possible, or would it be too fragmented? Tollund Man’s brain is apparently sufficiently well-preserved, after 2500 years, to allow extraction of genetic material.

A couple of weeks after finding the Beckfoot forest, I went down to the shore again. It was during the final weekend of February, when the Gaels and Celts were struggling through blizzards but Cumbrians were enjoying clear blue days and views of snow-dusted Fells. The Silly Bitch (our “failed” working-dog, the border collie) was, as usual, running her clockwise circles on the sand as we walked towards Dubmill, and a group of seals had apparently gathered for a meeting on the shore; except that the circle of bodies, heads raised, had been carved from banks of peat that had been tilted and tumbled together in a hollow, about 5-6 metres below the level of the road. Pieces of branch or root were exposed at the edges of the blocks and I was thrilled to find a football-sized lump of green slippery clay lay nearby – presumably the boulder clay above which the trees had grown, torn up from deep beneath the peat – but, as usual, there was nobody nearby with whom to share this exciting find! There was no way to tell whether the trees had been drowned by sea or by peat all those thousands of years ago, but now the whole thick organic mass had been finally overwhelmed by the Solway tides. The forest floor on which the Silly Bitch and I were standing extended inland, a layer of trees preserved deep beneath the fields and dunes and mire. Next time we go back to Allonby, the remains may have been buried yet again, beneath the sand and gravel on the shore.

And incidentally, there is a bank of peat and wood on the Beckfoot shore that is riddled with tunnels from which the white shells of long-dead piddocks protrude. Piddocks are bivalve molluscs that normally burrow in rock; “ship-worms” are the bivalves that are supposed to burrow in wood. What on earth has been going on? The Solway’s submerged forests are certainly full of mysteries.

 

[Solway AONB is based at the Discovery Centre, Silloth, where there is an excellent exhibition about the area’s geology, history and wildlife; the centre also runs guided walks along the shore. Tel: 016973 33055 www.solwaycoastaonb.org.uk]

Ann is the author of several novels, the most recent of which is The Embalmer's Book of Recipes - I enjoyed it enormously and thoroughly recommend it. I posted a brief review on the Goodreads site:

 
I was surprised - read because I know the author, and a book that I would not necessarily select off a book store shelf. But I found it compelling, fascinating - and informative, not to mention beautifully written. A story of three very different women, set in the English Lake District farming and academic communities, Lingard weaves a seemingly unlikely tale of relationships, handicaps (physical and emotional), aspirations, agricultural challenge, and the arcane history of embalming and eugenics, into a haunting narrative. Humorous and human, full of insights - a thoroughly engaging read.

Visit Ann's website at http://www.annlingard.com/

Reports from the Solway Firth (1): beauty and violence

 

In many ways, I can't think of a better way to start the day. Last Wednesday morning I had the pleasure of walking on the beach near Mawbray on the Solway Firth, the great estuary that marks the boundary between England and Scotland (Hadrian's Wall comes down to the sea at its mouth), overlooked by the hills of the Lake District and the Southern Uplands. Yes, it was windy and cold, but as the photo at the head of this post suggests, it's a place of extraordinary beauty, a landscape that invites reflection on its story, its testaments. For there is another side to this landscape, one of violence and power.

Why was I so far away from London that morning? To give a talk, that previous evening, a date long agreed on and by the kind invitation of the local Café Scientifique group. The traditional location for the talks was a traditional brewery, which struck me as an ideal location, and I had been looking forward to the event for some time. The Jennings Brewery has been brewing fine ales since 1828, and since 1874 in the location shown in the photo below.

 

A superb setting, under the walls of the old castle, whose well provides one of the key ingredients, and at the meeting of two rivers, the Cocker and, having flowed scenically from its origins in the heart of the Lake District, the Derwent. But it's the Cocker that gives its name to the confluence town where the brewery is located - Cockermouth. Yes, the town that just over two weeks earlier had suffered for its setting, a foot of rain in twenty-four hours causing the two rivers to change their mood and their courses, violently, devastatingly, flooding the town, beauty gone berserk. The Jennings Brewery was under five feet of water.

I contacted the organiser of the Café Scientifique, whom I had known for some time (and you will meet in the next report), most importantly to check on her situation, but also under the assumption that the event would have to be postponed - surely the local residents, enthusiastic as they might be for all things scientific, had other priorities? My friends were fine, on high ground in an outlying village and expressed a determination that an alternative venue would be found and the event would go ahead. Which it did - at a warmly hospitable café (I suppose strictly more appropriate than a "Brewery Scientifique") with mince pies and shortbread biscuits/cookies and copious red wine. The place was packed, most of the audience having arrived before I did, and they were fantastic. Human nature can be wonderful and uplifting.

So, since I had requested - weather permitting - a morning excursion to the coast, there I was on the beach, the timing perfect with sun and an outgoing tide, good company and an enthusiastic dog. But the evidence for violence was also apparent. The weather system and the deluge that had devastated Cockermouth and other valley towns had also hit the coast, where, even under normal circumstances, the tides and currents are immense. My companion, a regular observer of this landscape, described how the rows of rotted wooden fish trap posts that we could see running out across the sand flats had barely been visible before. Huge volumes of sand scoured away and flushed violently up the coast. This process was evident from the dramatic series of large sand waves visible high on the beach, just below the eroding dunes (photos below, dog for scale), their shoreward boundary dramatically linear and all suggestive of high velocity water movement.

 

My friend described how she had found a dead sheep on the beach, washed down the river and along the coast. And then, this reminder of nature's violence struck home with the memory of human tragedy. Down the river from Cockermouth is the village of Workington; there, at the height of the chaos, Police Constable Bill Barker was bravely directing motorists off a threatened bridge when the structure collapsed beneath him. His body was found on the beach just to the south of where I stood that morning, twelve miles from the remains of the bridge.

Tragedy and wholesale devastation as a result of flooding is nothing new to this region - Cockermouth has been hit before (but not on this scale), the local city of Carlisle last experienced major floods in 2005, and the entire area around the Solway Firth was flooded that night a few weeks ago, including large areas of southern Scotland. And historically this has always been the case - the following is a passage from Charles Lyell's classic Principles of Geology, first published in 1830:

One of the most memorable floods of modern date, in our island, is that which visited part of the southern borders of Scotland, on the 24th of January, 1794, and which spread particular devastation over the country adjoining the Solway Firth.

We learn from the account of Captain Napier, that the heavy rains had swollen every stream which entered the Firth of Solway, so that the inundation not only carried away a great number of cattle and sheep, but many of the herdsmen and shepherds, washing down their bodies into the estuary. After the storm, when the flood subsided, an extraordinary spectacle was seen on a large sand-bank, called "the beds of Esk," where there is a meeting of the tidal waters, and where heavy bodies are usually left stranded after great floods. On this single bank were found collected together the bodies of nine black cattle, three horses, one thousand eight hundred and forty sheep, forty-five dogs, one hundred and eighty hares, besides a great number of smaller animals, and, mingled with the rest, the corpses of two men and one woman.

In one of the chapters of my book, a sand grain takes a journey down a river, the Susquehanna, and for the epigraph I liked the following from Ralph Waldo Emerson's “Woodnotes II”

The river knows its way to the sea;

Without a pilot it runs and falls,

Blessing all lands with its charity.

While the chapter includes descriptions of rivers in flood, I felt, that evening last week, that I should start the talk with an apology to the citizens of Cockermouth for an introduction that only shows one side of the fluvial coin. Beauty and violence - the way our earth works.

 

[Cockermouth flood photos The Guardian, Scott Heppell/AP, http://edwardthesecond.blogspot.com/2009/11/photos-and-floods.html, and the British Geological Survey. The complete Principles of Geology can be accessed online at http://www.naderlibrary.com/lyell.toc.htm or http://www.esp.org/books/lyell/principles/facsimile/. Jennings Brewery will be back up and running by mid-January]

 

"Free Spirit" update - things are looking worse

Since Spirit has been travelling backwards for a long time, dragging its right front wheel behind it, it's easy to lose track of orientations and what's going on where. The image below is taken from the front of the rover, but looking backwards, and the disabled wheel, the right front, is at the right. When I was reading about the failed attempts to move the rover, as I reported in the previous post, I hadn't realised that the stalled wheel that ended the test was the right rear wheel that had, up until now been functioning reasonably well. It now seems very likely that the right rear wheel has ceased to function and this leaves Spirit with only four working wheels, three of which are more or less buried.

 

It's therefore, as the New Scientist reported a couple of days ago, looking even more grim:

Now, Spirit's right-rear wheel is also having problems and may be permanently disabled.

The right-rear wheel stalled on 28 and 21 November during attempts to start driving the rover out of the sand trap. Each wheel has its own motor, and the rover team commanded Spirit to try to spin the wheel again during a series of tests on 3 and 4 December – but it did not budge.

In the previous stalls, the wheel had at least moved a little bit before unexpectedly stopping. But no motion at all was detected in the tests.

"That's troubling," says rover project manager John Callas of NASA's Jet Propulsion Laboratory in Pasadena, California. "It's conceivable we're witnessing a deterioration on the wheel."

If the wheel cannot be coaxed into working again, then Spirit will likely be trapped forever, Callas says.

"It was questionable whether we could get a five-wheel-driving rover out," he says. "If we have a four-wheel-driving rover [with] only one driving wheel on the right-hand side ... then extracting the rover from its current embedded location is unlikely."

Spirit could die if it remains stuck when winter arrives six months from now at the rover's location in Mars's southern hemisphere, Callas says.

In previous winters, Spirit rested on slopes that angled its solar arrays in a way that captured as much sunlight as possible. That allowed the rover to power heaters designed to keep its electronic innards from freezing.

But Spirit's solar panels are not currently at a good angle to maximise sunlight. Meanwhile, dust is slowly accumulating on the panels, reducing their efficiency. If the rover is unable to move, it could run out of power and die in the frigid Martian night.

"If we extrapolate current dust accumulation rates out to the next winter six months away, it does look troubling," Callas says. "There's a real possibility Spirit would not have power to survive the winter at its current attitude."

"Free Spirit" campaign - but it doesn't look good for the Mars Rover

 “It’s way out of warranty,” said Ray Arvidson, director of the Earth and Planetary Remote Sensing Laboratory at Washington University in St. Louis. “It’s like an old ’55 Chevy.” He was talking about the intrepid Mars Rover, Spirit, that has, along with its sibling on the other side of the planet, Opportunity, been trundling around for six years of a mission that was expected to last three months. In 2006, Spirit's right front wheel stopped working and so it continued backwards, dragging the wheel behind it. Then, in April of this year, having been working around an area known as "Home Plate", a miniature plateau just 80 meters (260 feet) across - see the image below - for more than three-and-a-half years, Spirit's wheels broke through a poorly cemented sand crust and the rover became stuck in the very fine loose sand beneath. And, as I wrote back in May, it was seriously stuck - the images were enough to strike horror into the heart of a field geologist and Arvidson described the situation as "Murphy's Law on steroids."

 

NASA have spent much of the last months setting up a test bed of fine sand of the the same character as that which has ensnared Spirit (see video), and working on possible minute manoeuvres to extricate the rover. These have now been put to the test - sadly with minimal results. The image at the top of this post is taken from NASA's report of a few days ago - and it looks awful. Total wheel movement during the attempt was 1.4 meters (4.6 feet) and "Analysis of data from the drive indicates that the center of the rover moved 0.5 millimeters (0.02 inch) forward, 0.25 millimeters (0.01 inch) to the left and 0.5 millimeters (0.02 inch) downward." Spirit was just spinning its wheels and the trial was stopped when the inactive right rear wheel stalled again. And, as if this weren't bad enough, communications with earth have been disrupted by problems with the Mars orbiting satellites.

But Spirit hasn't just been sitting there twiddling its robotic thumbs. As the New Scientist recently reported:

Spirit has been immobile for the past six months, but it has not been idle.

The rover's own observations have revealed the cause of its plight - a small crater filled with yielding, yellow-brown sand. The sand had been hidden beneath a dust-covered crust of weakly cemented sand particles.

Spirit's wheels punched through this centimetres-thick crust, exposing soil with the highest concentration of sulphate minerals ever found by either Spirit or its twin, Opportunity.

Sulphates form in the presence of water, so the find further reinforces the idea that, billions of years ago, the area surrounding Spirit was rich in the liquid.

Researchers suspect Spirit's stomping ground was once a site of intense hydrothermal activity. Pools of hot water and steam vents may have dotted the area, making it a good place for future missions to look for evidence of ancient Martian life, says Spirit scientist Ray Arvidson of Washington University in St Louis, Missouri. "If it were Earth with that kind of environment, it would be teeming with microbes," he says.

Nonetheless, the rover team is keen to move on. "It's an interesting area to be in over the summer," says Arvidson, "but we're ready to leave."

Meanwhile, the other rover, Opportunity, continues its successful ramblings - it's travelled 19 kilometers (nearly 12 miles) so far, 2.4 times the distance of Spirit's trek. But Opportunity has also had its problems with sand along the way - in April 2005, after speeding along at a reckless 200 meters per day,  it was stuck for five weeks on a ripple named "Purgatory Dune" but was successfully extricated. But lessons were learned: when, a year later it became embedded in a sandy spot nicknamed "Jammerbugt" (apparently the Danish for "bay of lamentation"), it was out and off again in no time.

For Spirit, the future is highly uncertain, with winter and dust storms approaching. The editorial in the New Scientist had the following comment about the '55 Chevy, something with which I think we would all agree:

NASA has been agonising over how to free Spirit from a sand trap for six months. That's double the design lifetime of the rover, which landed in 2004. Now, with winter on the way, NASA's hand is forced. Its plan is to backtrack slowly out of the mire. One could criticise the agency for investing too much effort in a mission that's past its prime, but that would be churlish: Spirit has achieved more than anyone dared dream, and could deliver yet more. Besides, it would seem strangely cruel to abandon the plucky rover to its fate.

 

"Climategate" - one voice of reason

No, that voice is not mine, but any voice of reason in the smoke and dust and the hysterical pronouncements surrounding the leaked e-mails is difficult to find; once found it deserves to be shared.

I try, imperfectly, to operate to some basic principles. One, relating to this blog, is that it is devoted to information, ideas, news and fun that interest me and illustrate the stories that sand can tell and the journeys it can take us on; it's been called a "niche" blog, and I'm happy with that. What it is not is a platform for my opinions (of which I readily admit to having many) or antagonistic debate. But just once in a while, something comes up that prompts me to make a brief exception, to stray from my theme into an area that is not strictly arenacaeous. I last did so over the Simon Singh case and the dire relationship between science and the British libel laws, and now "climategate" prompts another departure.

Another principle that I try to adhere to in life in general is that, in public and professional life, I will only express my views on topics that I know something about; privately (as my wife will testify to), I can become vocally excited about all kinds of issues. As a scientist, I am particularly exercised by the portrayal of our world in exclusively black and white terms by individuals and organisations with axes to grind and by people who set themselves up to pontificate on topics for which they have no credentials to do so. If science tells us anything, it's that we live in world characterised by a glorious spectrum of shades of gray, a spectrum that we should relish rather than seek to portray it as black and white. 

As, over the last week or so, I have sought facts or at least authoritative and credible opinion on the case of the Climatic Research Unit e-mails, it has been once again driven home to me how naive I am in restricting public pronouncements to topics on which I like to think I have some credibility - the media and the internet are, in many ways, a free-for-all. In the UK recently, for example, we have been treated in the Guardian and television's Channel 4 news (neither of them exactly from the muck-raising hysterical end of the media spectrum) to the views of the founder of "The Global Warming Policy Foundation." Now this title would seem to carry intellectual gravitas - I certainly presumed so. Until I discovered that the founder is a social anthropologist in the Department of Sport and Exercise Sciences at Liverpool's John Moores University (as distinct from Liverpool University) and that the chairman (and co-founder) is Nigel (sorry, Lord) Lawson, Chancellor of the Exchequer under Margaret Thatcher and prominent denouncer of climate science.   

Irritated, but undeterred, I continued with my quest. And I found Mike Hulme, Professor of Climate Change in the School of Environmental Sciences at the University of East Anglia and founding Director of the Tyndall Centre for Climate Change Research, a body with, for me, greater credibility than the Global Warming Policy Foundation. He's the author of Why We Disagree About Climate Change, a book recently published by Cambridge University Press (and one that I should now read), and a thoughtful - and informed - commentator on these issues. In an atmosphere within which some scientists seem, quite frankly, to have lost the plot and provided grist to the cacophonous mills of those who make a living out of vilifying science, Hulme's is a refreshing voice of reason. A couple of days ago, the online Wall Street Journal carried a piece by him that struck me as excellent, and so I have reproduced it below; for further reading, try The Five Lessons of Climate Change: a personal statement, and much more via his website.

The Science and Politics of Climate Change

Science never writes closed textbooks. It does not offer us a holy scripture, infallible and complete.

By Mike Hulme 

I am a climate scientist who worked in the Climatic Research Unit (CRU) at the University of East Anglia in the 1990s. I have been reflecting on the bigger lessons to be learned from the stolen emails, some of which were mine. One thing the episode has made clear is that it has become difficult to disentangle political arguments about climate policies from scientific arguments about the evidence for man-made climate change and the confidence placed in predictions of future change. The quality of both political debate and scientific practice suffers as a consequence.

Surveys of public opinion on both sides of the Atlantic about man-made climate change continue to tell us something politicians know only too well: The citizens they rule over have minds of their own. In the U.K., a recent survey suggested that only 41% believed humans are causing climate change, 32% remained unsure and 15% were convinced we aren't. Similar surveys in the U.S. have shown a recent reduction in the number of people believing in man-made climate change.

One reaction to this "unreasonableness" is to get scientists to speak louder, more often, or more dramatically about climate change. Another reaction from government bodies and interest groups is to use ever-more-emotional campaigning. Thus both the U.K. government's recent "bedtime stories" adverts, and Plane Stupid's Internet campaign showing polar bears falling past twin towers, have attracted widespread criticism for being too provocative and scary. These instinctive reactions fail to place the various aspects of our knowledge about climate change—scientific insights, political values, cultural moods, personal beliefs—in right relationship with each other. Too often, when we think we are arguing over scientific evidence for climate change, we are in fact disagreeing about our different political preferences, ethical principles and value systems.

If we build the foundations of our climate-change policies so confidently and so single-mindedly on scientific claims about what the future holds and what therefore "has to be done," then science will inevitably become the field on which political battles are waged. The mantra becomes: Get the science right, reduce the scientific uncertainties, compel everyone to believe it. . . and we will have won. Not only is this an unrealistic view about how policy gets made, it also places much too great a burden on science, certainly on climate science with all of its struggles with complexity, contingency and uncertainty.

The events of the last few of weeks, involving stolen professional correspondence between a small number of leading climate scientists—so-called climategate—demonstrate my point. Both the theft itself and the alleged contents of some of the stolen emails reveal the strong polarization and intense antagonism now found in some areas of climate science.

Climate scientists, knowingly or not, become proxies for political battles. The consequence is that science, as a form of open and critical enquiry, deteriorates while the more appropriate forums for ideological battles are ignored.

We have also seen how this plays out in public debate. In the wake of climategate, questions were asked on the BBC's Question Time last week about whether or not global warming was a scam. The absolutist claims of two of the panelists—Daily Mail journalist Melanie Phillips, and comedian and broadcaster Marcus Brigstocke—revealed how science ends up being portrayed as a fight between two dogmas: Either the evidence for man-made climate change is all fake, or else we are so sure we know how the planet works that we can claim to have just five or whatever years to save it. When science is invoked to support such dogmatic assertions, the essential character of scientific knowledge is lost—knowledge that results from open, always questioning, enquiry that, at best, can offer varying levels of confidence for pronouncements about how the world is, or may become.

The problem then with getting our relationship with science wrong is simple: We expect too much certainty, and hence clarity, about what should be done. Consequently, we fail to engage in honest and robust argument about our competing political visions and ethical values.

Science never writes closed textbooks. It does not offer us a holy scripture, infallible and complete. This is especially the case with the science of climate, a complex system of enormous scale, at every turn influenced by human contingencies. Yes, science has clearly revealed that humans are influencing global climate and will continue to do so, but we don't know the full scale of the risks involved, nor how rapidly they will evolve, nor indeed—with clear insight—the relative roles of all the forcing agents involved at different scales.

Similarly, we endow analyses about the economics of climate change with too much scientific authority. Yes, we know there is a cascade of costs involved in mitigating, adapting to or ignoring climate change, but many of these costs are heavily influenced by ethical judgements about how we value things, now and in the future. These are judgments that science cannot prescribe.

The central battlegrounds on which we need to fight out the policy implications of climate change concern matters of risk management, of valuation, and political ideology. We must move the locus of public argumentation here not because the science has somehow been "done" or "is settled"; science will never be either of these things, although it can offer powerful forms of knowledge not available in other ways. It is a false hope to expect science to dispel the fog of uncertainty so that it finally becomes clear exactly what the future holds and what role humans have in causing it. This is one reason why British columnist George Monbiot wrote about climategate, "I have seldom felt so alone." By staking his position on "the science," he feels alone and betrayed when some aspect of the science is undermined.

If climategate leads to greater openness and transparency in climate science, and makes it less partisan, it will have done a good thing. It will enable science to function in the effective way it must do in public policy deliberations: Not as the place where we import all of our legitimate disagreements, but one powerful way of offering insight about how the world works and the potential consequences of different policy choices. The important arguments about political beliefs and ethical values can then take place in open and free democracies, in those public spaces we have created for political argumentation.