Scott’s Hut: revisited

Few people conjuring up the “most comfortable dwelling place imaginable” are likely to picture a wooden shelter on an island off the coldest continent on Earth. But that’s how Antarctic explorer Robert Falcon Scott described the hut at Cape Evans that was the base for his 1910-13 Terra Nova expedition.

The hut is nestled below a small volcanic hill on a long stretch of black sand. I’ve been there twice, when it looked like a building site in 2011, and again on a sunny day last December. On my second visit, seals lay on the sea ice in front of the newly restored structure and sun glinted off the ice cliffs of the nearby Barne Glacier.

The New Zealand Antarctic Heritage Trust recently announced the completion of 10 years of intensive work to save three historic buildings on Ross Island. As well as the hut at Cape Evans, it has been working on the Discovery Hut from Scott’s 1901-04 expedition, at Hut Point, and the hut at Cape Royds, built for Ernest Shackleton’s 1907-09 Nimrod expedition.

On my first Cape Evans hut visit, many of the artefacts had been removed while carpenters repaired the walls, floors and roof. This time, the hut contents had been returned, and Lizzie Meek, a specialist paper conservator and the trust’s programme manager for artefacts, showed me around. In Scott’s “zone of command” was the table – now home to a stuffed emperor penguin and a 1908 edition of the Illustrated London News – where Edward Wilson made his enduring biological illustrations. In a dark corner nearby, Edward Atkinson had incubated his moulds and parasites. My favourite space, though, was the small workbench and array of test tubes, sample jars and Bunsen burner stands of biologist Edward Nelson, lit by sunshine through a murky window. This was where the young scientist preserved marine specimens – fish, krill, starfish and more – as part of his search for new species and an understanding of the Antarctic food chain.

Inside Scott's newly restored hut at Cape Evans.

Inside Scott’s newly restored hut at Cape Evans.

Trust executive director Nigel Watson describes the three restored huts as “fantastic remnants of humans’ first contact with the continent”. The genesis of the conservation project, he says, “was the fact that we were in great danger of losing them”. When the on-site work began in 2004, snow and ice were building up around, under and sometimes inside the huts, damaging the structures and threatening their contents.

“We now have three buildings that are structurally sound and watertight with a very different feel – they are drier and lighter and the humidity is reduced. It’s a much better environment for the collection.”

As well as heritage carpenters, the trust team has included specialists in textile, paper and metal conservation: in total, 62 experts from 11 countries have visited Antarctica to work on the project, often spending months on-site, sleeping in tents and popping 25km back to Scott Base for the occasional shower. “It became known as the most exciting conservation project in the world,” says Watson, “so it attracted top heritage conservation talent.”

Some of the most exciting discoveries were three intact crates of “Mackinlay’s Rare Old Highland Malt Whisky” found encased in ice beneath Shackleton’s hut, a notebook that belonged to surgeon, zoologist and photographer George Murray Levick found buried in dirt at Cape Evans and a small box of 22 cellulose nitrate negatives found in Herbert Ponting’s darkroom in the Terra Nova hut.

But most of the 18,202 items catalogued and conserved are more mundane: food, tools, clothing and other personal items that were not precious enough to be taken home on the return voyages.

The trust’s conservation treatments involved “removal of degradation products followed by chemical treatment to either slow, or in some cases reverse, the deterioration”, said Meek when we spoke again last week. Metal items would go through corrosion removal, followed by a chemical stabilisation treatment, then application of an oxygen and moisture barrier to prevent further corrosion. Treatment of paper items often involved washing “to dissolve harmful acids and salts and to help the fibres to reknit, often resulting in the paper having a stronger cohesion”.

As a result of the project, the trust has become the world leader in cold-climate heritage conservation. Next summer, its skills will be applied to a new challenge. The Ross Island huts are the “jewels in the crown”, says Watson, but there are other historic buildings needing attention. With logistics support from Antarctica New Zealand, programme managers Al Fastier and Meek will be part of a small team heading to Cape Adare, an exposed site more than 700km north of Scott Base. The two Cape Adare huts, remnants of an 1898-1900 British expedition led by Carsten Borchgrevink, “are not only the first buildings on the continent”, says Watson, but also “the only example of humanity’s first buildings on any continent on Earth”.

Inside Scott's hut.

Inside Scott’s hut.

The three-year restoration effort will involve building repairs and the removal, conservation and return of about 1100 objects. Compared with the relatively sheltered hut sites on Ross Island, Cape Adare is “a very remote and challenging place to work in”, says Watson. “It’s set among the world’s biggest Adélie penguin colony on an exposed spit of land and these little wooden buildings are just perched there, defying the elements.”

Meek looks forward to the challenge. “But I’m also looking forward to going back to the Ross Island huts and seeing them with fresh eyes. After so many years of working on them, to be able to step inside and look around to see what we have accomplished will be amazing.”

If you can find your way to Antarctica, you’ll need a permit to visit any of the Ross Island huts, which are each in an Antarctic Specially Protected Area. But there’s an easier way to see them: the trust has partnered with Google to offer Street View walkthroughs of each of the dwellings, available via Google Earth or through the trust’s website at

This story was first published in The Listener at

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Breathless in Antarctica

Camping in Antarctica last December, I noticed that even though it was extremely cold, -10°C to -20°C, our exhalations didn’t make visible clouds. When the helicopter landed to pick us up, though, our breath appeared as dense white clouds. Why was this?

Adam Lewis and Tim Naish before heading off for Friis Hills: Adam demonstrating the visible breath around helicopters phenomenon.

Adam Lewis and Tim Naish before heading off for Friis Hills: Adam demonstrating the visible breath around helicopters phenomenon.

Adam Lewis, a glacial geologist from North Dakota State University, initially made this observation while we were walking in the Friis Hills, a 1300m-high plateau about 50km up the Taylor Valley in the Dry Valleys region of Antarctica. Part of a group of geologists led by Tim Naish from Victoria University’s Antarctic Research Centre and Richard Levy from GNS Science, we speculated as to what extent the lack of visible breath had to do with the dryness of the air and the lack of cloud condensation nuclei.

The clouds we expect to see when someone exhales on a cold day are made from tiny droplets of liquid water. These out-breaths create a visible cloud for the same reason clouds form in the sky. Air – which is primarily composed of nitrogen and oxygen – also contains a small amount of gaseous water, and the warmer the air, the more water gas it’s capable of holding. When air cools, it can hold less water gas, and some of the gas will condense out of the air and start to form droplets of liquid water. In sufficient quantities, these droplets can form a visible cloud. Droplets of liquid water tend to form around condensation nuclei, tiny particles of sea salt, dust, clay or soot.

We started talking about the invisible breath issue when Adam Lewis took us for a walk over the Friis Hills.

We started talking about the invisible breath issue when Adam Lewis took us for a walk over the Friis Hills.

Back in Wellington, I asked MetService’s Erick Brenstrum why our ­Antarctic breath-clouds were different from those we experience in New Zealand.

“When you breathe out, you’re breathing warm air with high water content,” he explained. In the Friis Hills, the warm, moist breath coming from our lungs would have mixed with the surrounding air, which had a temperature of about -10°C and perhaps only 10% humidity (compared with the 60-90% humidity typical of New Zealand). As warm air from our lungs mixes with the cold air outside, “it cools, and wants to make a cloud. But if the air it’s mixing with is incredibly dry, the water gas is never going to reach a concentration where it forms a liquid and makes a cloud. So if you’re in an incredibly dry environment, even when you breathe out high-humidity air, you don’t get a cloud.”

So what difference did the proximity of the helicopter make? “When you burn fuel in an engine, one of the by-products is water gas. So it could be that locally, under and around the helicopter, you’re suddenly getting a large quantity of water gas. So when you breathe out moist air, you’re able to reach 100% humidity and you get a little cloud.”

Condensation nuclei play a part too. “It’s highly likely that pollutants from the burning of the fuel would act as condensation nuclei. It’s also likely there would be some on the ground, thrown up by rotor action.”

That said, a definitive answer to this question would demand controlled testing and repeatable results. Perhaps a good reason to return to Antarctica?

This story was originally published in The Listener


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A tribute to my father: Nigel Priestley (1943-2014)

First published in the Listener, issue 3898, 22 January 2015.

One day, shortly before I started school, my father took me to his work at the Ministry of Works’ central laboratories, where he was head of structures. When his colleagues asked the inevitable, “How old are you?” I replied – just as Dad had coached me to – “Four point nine five.”

It got a laugh from his colleagues, who I’m sure appreciated the accuracy of my reply. An affinity for numbers and precision, along with rigorous attention to detail, is something we often undervalue, but in professions such as engineering they’re essential.

Me and Dad. Pretty sure I was older than four point nine five in this picture … perhaps six point two five or so? Photo by Jule Einhorn.

Me and Dad. Pretty sure I was older than four point nine five in this picture … perhaps six point two five or so? Photo by Jule Einhorn.

My father, Nigel Priestley, was a structural engineer who worked at universities in New Zealand, the US and Italy and whose consulting work took him to earthquake-prone countries around the world. According to Quincy Ma, president of the New Zealand Society for Earthquake Engineering, Priestley “revolutionised the design of structures to resist earthquakes” over the course of his career.

He died just before Christmas. His many awards and accolades, including an ONZM for services to structural engineering, have been noted in obituaries. But he was more than an engineer. He also read and wrote poetry, played classical guitar and was an accomplished carpenter. I think it was this mixture of precision and creativity that led to his best work, which was marked by a fresh way of looking at engineering problems and demonstrated in book-length accounts of how to apply these new ideas to the design of structures, particularly buildings and bridges.

Priestley’s “full metal jackets” – a cost-effective retrofitting system in which concrete bridge columns are wrapped in steel to reduce the risk of them collapsing in an earthquake – are now widely used in Californian bridges and highways and were adopted for the retrofit of the Thorndon overbridge in Wellington.

My favourite photo of me and Dad. This is at the IPENZ dinner in 2013, when he was being made a Distinguished Fellow of the Institute of Professional Engineers of New Zealand. I think he looks more like a secret agent than a structure engineer. Photo Ana Priestley.

My favourite photo of me and Dad. This is at the IPENZ dinner in 2013, when he was being made a Distinguished Fellow of the Institute of Professional Engineers of New Zealand. I think he looks more like a secret agent than a structure engineer. Photo Ana Priestley.

His most revolutionary move, though, was to reject the traditional force-based design that had dominated seismic engineering for its 60-year history and embrace and promote displacement-based design. This approach gives a better understanding of the forces and displacements within a structure and led to fundamental changes in the way new buildings are designed. Significantly, it allows engineers to actually dictate how a structure will respond in an earthquake. This philosophy was detailed in Displacement-Based Seismic Design of Structures,a 2007 book written by my father and colleagues Michele Calvi and Mervyn Kowalsky.

“The methodology set out in the book is rapidly replacing internationally the traditional force-based design methods,” says Richard Sharpe, Beca’s technical director of earthquake engineering.

Another significant advance in earthquake-resistant design is Presss (precast seismic structural system), developed by a team my father led. Whereas in the past buildings were designed to absorb force and crunch and grind at certain structural points, this new system designs buildings as a series of rocking blocks that can move independently of each other. To stop the blocks tumbling down in an earthquake, they are held together by steel tendons that allow the blocks to move but always pull them back to their original position. The beauty of this system, and the reason it’s being widely applied in the Christchurch rebuild, is that not only can you ensure lives are safe “but you also minimise the damage to the building or restrict damage to elements that can be easily replaced after the earthquake”, says Sharpe.

I returned to work this week in the Alan MacDiarmid Building at Victoria University, the first multi-storey building in New Zealand to use the tendon and rocking Presss system. I’m thankful for my father’s precision and attention to detail and to this country’s community of structural engineers who work to protect lives and property in these shaky isles and around the world.

The Alan MacDiarmid Building at Victoria University of Wellington, where I work. It rocks and rolls in an earthquake (I experienced a 6.6 in mid 2013) but doesn't crunch and grind. Photo Victoria University of Wellington.

The Alan MacDiarmid Building at Victoria University of Wellington, where I work. It rocks and rolls in an earthquake (I experienced a 6.6 in mid 2013) but doesn’t crunch and grind. Photo Victoria University of Wellington.

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Pathogens, sediments and nutrients: the nasties making our rivers unsafe

This was first published in the Listener, 31 July 2014.

When I was a kid, in the 1970s, the only “unsafe” water I was aware of was the geothermal hot pools of the Taupo Volcanic Zone. If you put your head under the water, I believed, an amoeba would swim into your ear and eat your brain. Or something like that.

I was happier swimming in cold water. On South Island holidays, we’d swim in freezing glacier-fed lakes and rivers. Sometimes, closer to home, we’d free camp on Wairarapa farmland and swim in the local rivers.

But I don’t think I’d take my children to some of the same swimming spots – especially the ones on farmland. In July 2013, the Ministry for the Environment reported that 61% of the river sites it monitored were unsafe for swimming and should be avoided. Annual reports on recreational water quality have now been dropped, so it’s hard to know if things are getting better or worse.

What makes our fresh water “unsafe for swimming”? In a 2012 report on the science of water quality, the Parliamentary Commissioner for the Environment said the three main water pollutants of greatest concern to our fresh water – rivers, streams, lakes, wetlands and estuaries – were pathogens, sediments and nutrients.

If you’re swimming, the biggest risk to your health comes from pathogens – bacteria or viruses – that can enter your body through your mouth, nose or ears. Pathogens can enter waterways through contamination from human sewage or animal manure; for example, from effluent run-off from farmland, human wastewater discharges, stormwater outfalls and domestic- and wild-animal waste.

Pathogen levels are often highest after rainfall when faecal matter is carried from the land into waterways. According to the environment ministry’s 2013 Suitability for Swimming indicator update, the potential human health effects of these pathogens are numerous, although mostly “minor and short-lived”.

The list includes “gastro-intestinal illnesses with symptoms like diarrhoea or vomiting, and infections of the eye, ear, nose and throat. However, there are other potentially more harmful diseases such as giardiasis, cryptosporidiosis, campylobacteriosis and salmonellosis. Hepatitis A can also be contracted from contaminants in the water and can lead to long-term health problems.”

Nutrients such as nitrogen and phosphorus are useful on land, where they can stimulate plant growth. But in water they can cause excessive growth of weeds, slime and algae and can be toxic – including for humans – at very high levels.

Most nitrogen in waterways comes from urine, through animals urinating in or close to streams, or from dairy-shed effluent. Phosphorus, spread as fertiliser on paddocks cleared of forest, washes into waterways along with soil, so levels of the element are closely linked to sediment load.

Accelerated erosion, mostly from deforestation, has increased the amount of sediment in our rivers. Sediment is not such a problem for humans – although it can obscure underwater hazards such as rocks and logs – but it can upset a waterway’s natural ecosystem by interfering with plant and animal life.

As for the amoeba that scared me in the 1970s, Naegleria fowleri is a single-celled animal that lives in the soil surrounding natural hot pools and is sometimes found in the water. Nancy Swarbrick writes on Te Ara that “diving into such pools or even immersing the head can force water up the nose, allowing the amoeba to invade the brain”.

There were nine fatal cases of amoebic meningitis between 1968 and 2000; commercial hot pools now filter water to keep it safe.

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Particle Fever review

The thing that differentiates scientists,” says physicist Savas Dimopoulos in Particle Fever, “is purely an artistic ability to discern what is a good idea, what is a beautiful idea, what is worth spending time on and, most importantly, what is a problem that is sufficiently interesting, yet sufficiently difficult that it hasn’t yet been solved.”

Theoretical physicist and Particle Fever producer David Kaplan describes the Higgs as “unlike any other particle … it’s the linchpin of the standard model … the crucial piece responsible for holding matter together”. The search for the Higgs boson involves the biggest and most expensive scientific experiment in history, involving more than 100,000 scientists from 100 countries. The Large Hadron Collider, a particle accelerator with a circumference of 27km, is designed to make two beams of protons collide with enough force to disturb the Higgs field – a theoretical field that fills all of space and gives particles mass – and create a Higgs particle.

The “beautiful idea” at the heart of this documentary, screening at the New Zealand International Film Festival, is the standard model of physics, a “theory of everything” developed in the 20th century. But the problem with this model, which was designed to explain the interactions between subatomic particles – all the different sorts of quarks, leptons and bosons – is that it made sense only with the existence of an undiscovered theoretical particle called the Higgs boson.

The documentary follows six physicists – theoreticians and experimentalists – from 2007, during the final construction of the Large Hadron Collider at the European Organization for Nuclear Research (Cern) in Switzerland, to the announcement of results in 2012.

“It’s big, no?” says Kaplan as he tours the magnet-filled underground tunnels. There’s a lot of big stuff in this movie – big instruments, big science, big intellects.

Installing the calorimeter for ATLAS, one of the four main experiments of the large hadron collider. Photo courtesy of CERN.

Installing the calorimeter for ATLAS, one of the four main experiments of the large hadron collider. Photo courtesy of CERN.

To people who question the value of the project, Kaplan says it might only help scientists to better understand the laws of physics. But he also points out that there could be unexpected spin-offs. The world wide web, for example, was invented at Cern as a way for physicists around the world to communicate with each other.

From the stylish opening title sequence, reminiscent of a 1970s paranoid thriller, to the final revelation, this is an intense and visually striking movie. There’s tension as this massive machine – “like a five-storey Swiss watch”, says one of the scientists – faces a lengthy shutdown and repairs, and as physicists wait to see if theories they’ve spent their lives working on are going to stand up in the face of experimental data.

At stake are two competing theories about the nature of the universe. Dimopoulos is one of the proponents of supersymmetry, the idea that the Higgs and the other particles of the standard model are part of a much bigger symmetry and there are many more particles yet to be discovered – hopefully by the Large Hadron Collider.

Younger theoretical physicist Nima Arkani-Hamed has a competing theory: that our universe is a tiny speck in a mostly inhospitable and random multiverse and the information we need to explain things such as dark matter could be hidden in other universes. On one side is “symmetry, beauty and order”, on the other chaos, randomness and “the end of physics”.

A lighter Higgs boson, about 115GeV (giga­electronvolts), would suggest supersymmetry. A heavier Higgs, about 140GeV, would favour the multiverse theory. Which will it be?

At a time when Hollywood is making monster movies about giant robots, this is a small but beautifully realised film about one of the biggest machines humankind has ever built. I look forward to seeing it on the big screen.

Particle Fever, directed by Mark Levinson, plays at the New Zealand International Film Festival:



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Call for papers – The Fukushima Effect: Nuclear histories, representations and debates

At the APSTSN conference in Singapore this July, I had the pleasure of meeting Richard Hindmarsh, associate professor at Griffith University, Australia, and editor of Nuclear Disaster at Fukushima Daiichi: Social, Political and Environmental Issues.

We were each presenting papers in a session entitled “States of Risk II”: Richard’s paper, Nuclear Disaster at Fukushima Daiichi: Social, Political and Environmental Issues – An Overview, introduced the major themes in his recent book. My paper, Nuclear Power: ‘A Malevolent Uncultured Arbiter of our Destiny or ‘A Servant of the Industrial Revolution’?, was about early attitudes to nuclear power in New Zealand. In our session, and in other parts of the conference, there were many other papers about nuclear histories and current attitudes to nuclear technology – many of them referencing the Fukushima disaster.

Richard and I got talking after our session, and kept on talking after the conference, and developed a plan for a follow up volume to Richard’s Nuclear Disaster at Fukushima book. We’re calling the new book The Fukushima Effect: Nuclear Histories, Representations and Debates and are currently seeking submissions.

Here’s some brief information about the aim of the book and the two areas it will cover:

Aim: to produce a high-quality edited book on the effect of the Fukushima disaster three years out from the disaster as another relatively early benchmark on this ‘effect’ and to determine the extent and scope of it, politically and culturally, on either:

Area 1: national histories, debates and policy responses on nuclear power development (in both well established ‘nuclear nations’ and emergent ones (apart from China, South Korea, Taiwan and New Zealand, for which we already have authors).

Area 2: long standing international and national debates in political and cultural context, such as the safety of nuclear energy, radiation risk, nuclear waste management, effect of radiation leaks on marine ecosystems, development of nuclear energy vis-à-vis other energy options, the moral debate, anti- nuclear protest movements, nuclear power representations, and so on.

Abstract submission deadline: 6 December 2013.

Send abstracts to:

Full details are contained in the attached pdf.

Call for papers Fukushima Effect

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