June 12, 2016

Disturbances #9: Cryolite to Cryoconite


Dirty snow and a melt pool on the Jakobshavn glacier, Ilulissat, Greenland
 

Last month I went to the desert again.

To Ilulissat, in Western Greenland. With precipitation averaging 247mm a year, it qualifies almost on a technicality - but I like the parallel to my previous trips too much not to play it. Peary Land in Greenland’s far northeast, meanwhile, is dryer than the Sahara.

So I’m writing about dust again: this time, Arctic dust. Dusty remains. Dust on the ice. Dust in the ice.

Dust that’s forecast to add at least 2cm to global sea level rise by 2100.

I swear (though it may sound unconvincing): I didn’t start this newsletter intending it to be about environmental devastation. I’ve got all this cute stuff about speculative architecture and the National Trust and, like, Derrida, all cued up in my drafts folder. But we go where the wind blows us - and, as I say, three weeks ago I finally went to Greenland.

I’ve been wanting to go since I was about 18, inspired by my great aunt’s stories of hiking across remote Icelandic tundra, and anthropology books about life at -40 below. I was curious how people lived in how people lived in such extreme environments, on the very threshold of the possible. And, after writing an undergraduate dissertation on the Soviet production of ‘state nomads’ in Siberia, I was interested in how indigenous livelihoods were intersecting with modernity. Greenland has, after all, been part of world systems since Paleo Eskimos migrated from the Russian Far East into northwestern Greenland in 2500 BCE.

The accelerating melt of its ice sheet will inundate world systems in the latter part of this century and beyond.

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There are many dusty stories as can be told about Greenland.

I could talk about the ghost towns abandoned after their mines were shut - Arctic analogues of the abandoned mining towns I visited in the desert southwestern United States last summer. Qullissat, on Disko Island. The marble quarry at Qaqortuatsiaq.

Ivittuut today (source: arctic-hunting-group.com)

One, Ivittuut, is the site of the first mineral - cryolite, an aluminium ore - so rare that it is possibly the first and only mineral on Earth ever mined to commercial extinction. Access to cryolite, a crucial ingredient for electrolysing bauxite ore to produce aircraft aluminium, was a major strategic justification for the United States taking over Greenland as a ‘protectorate’ in WW2, in order to maintain Allied supplied lines after Germany invaded Denmark.

Thule Air Base was built at 77 degrees north (and 132 Greenlanders evicted from their homes) as a means of ensuring US dominance over the Arctic - and as an early warning system for incoming Russian missiles. In 1960, Operation ‘Chrome Dome’ saw the US Air Force start flying nuclear-armed B-52 Stratofortresses to the borders of the Soviet Union, twelve bombers scheduled to be airborne at all times. On 21 January 1968, one of these planes suffered a cabin fire and crashed. Four 1.1 megaton hydrogen bombs detonated on impact, spreading radioactive material over a large area of land and sea ice; a de facto dirty bomb. A clean-up operation in the black of an Arctic winter; -40C and below, 90 mph winds. Fairly impressively, 93% of contaminated material was removed from the site, and a 2003 report found that the plutonium left in the marine environment presents “insignificant risk”.

On land, however, “the plutonium contamination of surface soil at Narssarssuk could constitute a small risk to humans visiting the location if radioactive particles are re-suspended in the air so that they might be inhaled.” (Nielsen 2006).  Dust, again, in other words.

Fortunately (or otherwise), Narsaarsuk is another one of Greenland’s many abandoned settlements.

I could talk about all the tiny settlements of Disko Bay and beyond, each a handful of houses perched on granite rocks where subsistence hunters lived and fished. The modernisation programmes in the 1950s and 60s saw the government in Nuuk, the capital, seek to modernise the country through centralisation of industry and labour - to move Greenlanders from subsistence fishing towards export production. The government wanted people to move to the towns, where they could work in fish processing factories. The relocation wasn’t forced, as such - but once the schools and shops and transport links were cut, people didn’t have that much choice, either.

A handmade map on the wall at the Ilulissat museum showed dozens of settlements that had vanished between 1921 and 2007 in the Disko Bay region alone. Ritenbenck, founded in 1755. All but two on Disko Island. Greenlanders might just head out to these places for a few days in the summer, now, to camp and fish.


You could perhaps even call the whole country a ghost town - a ghost subcontinent - for at least 700 years of its history.

Greenland’s early Paleo Eskimo cultures - Dorset I on the east and west coasts, and Independence II in the north east - had both died out or departed the country by about 0 AD for reasons unknown but likely climatic. (A series of too-hard winters. A series of not-hard-enough winters meaning insufficient sea ice for hunting. Either could have done down a band of just a few thousand people.) The country was left empty until about 700 AD, when the Dorset II culture arrived into the far northwest from Canada. For the Vikings, arriving in 985 from Iceland into the far south, the country would have seemed empty too.

It was only around 1200 AD that the Thule Inuits, the ancestors of today’s Greenlanders, migrated into the country, again from Canada, and moved down to the lower southern latitudes to encounter the Vikings (who called them 'skraelings'). In turn, for hundreds of years Thule legends persisted about the mysterious Tuniit people, great giants taller and stronger than the Inuit, but who were easily scared off - most probably, the late Dorsets they superseded.

Chronology of migration to Greenland (source: geus.dk)


It’s a history that’s almost invisible on the land, though. Igloos and skin tents don’t leave many traces. Turf houses return quickly to the ground. In Ilulissat we visited - or rather walked past - the settlement of Sermermiut, inhabited across 4,000 years until the late 1800s. Archaeology here provided the first evidence of Greenland’s multiple waves of migration. All that’s there to be seen now, though, is a few low rising mounds in the grass of a sheltered little bay.

*

Almost all of Greenland’s human history takes place on the narrow fringe of habitable land around the coast. The culture looks out to sea: for transport (there are no roads between settlements), for livelihoods (fishing makes up 85% of Greenland's exports), and for hunting out on the sea ice in winter.

The ice sheet in the centre, a 1.7 million km sq expanse second only to Antarctica, supports no plants or animals, and thus no human life either - barring the occasional dog sled expedition across, or now, half a dozen scientific research stations camped on top.

Flying over in a plane to or from Canada, the ice may look dazzling white - a pristine and sterile landscape, alien in its inhospitability. It’s not. Look closely and you’ll see other colours. First, a deep cobalt blue, perhaps from glacial lakes melting the top layer of snow, or perhaps from the piteraq, a katabatic wind over 100mph, which strips the snow from the surface, both revealing the older, compressed ice beneath.

Seasonal meltwater lakes on the ice sheet, July 2006
(photo: Ian Joughlin, UW Polar Science Center, via NASA)

 

The snow could also be pink. In 1818, a British expedition looking for the Northwest Passage to the Pacific, led by Captain John Ross, reported “crimson snow that streaked the white cliffs like streams of blood” near Cape York, in Baffin Bay. The expedition believed it to be caused by iron-nickel meteroite detritus; the actual culprit is algae - Chlamydomonas nivalis, a species of green algae that carries an intense red, carotenoid pigment. It’s also sometimes called watermelon snow, as it’s also supposed to smell slightly sweet - though it’s not as tasty as that sounds: the algae is in fact a laxative.

The ice sheet may also be brown or black - from dust. In fact, that’s how the algae get here too: in dust on the wind.

I wrote in my first newsletter about the 182 million tons of Saharan dust that feeds the Amazon rainforest. Greenland, too, is part of this global mineral circulation, collecting dust mostly from the Chinese-Mongolian desert, and loess deposits in Central and Eastern Europe. Ten percent is Pacific Rim tephra, the rock fragments and glass shards emitted through volcanic activity. (Ujvari et al. 2015)

The dust that falls on the ice is known as cryoconite. The first Westerner to observe and name it was Arctic explorer Nils A. E. Nordenskiöld, in 1870, who described ‘cylindrical ice pipes’ about 1-2 feet deep and a few inches in diameter, containing ‘remarkable powder’ at the bottom - which hampered his Greenland crossing by making the ground too uneven to walk on. Nordenskiöld, and later Fritjof Nansen in 1900, studied the composition of cryoconite granules and the “dirty, grayish, or even brownish” dust on the ice surface between the holes, to see what it contained, finding both mineral components (quartz, feldspar and augite) and biological (algae). The dark colour of these cryoconite granules absorbed more heat from the sunlight than the surrounding snow, thereby melting the particles into the ice. (Cook 2015)

So the ice is alive - and dirty.

Visibly dirty. Jason Box (@climate_ice on Twitter and leader of the first crowdfunded scientific expedition to Greenland, the Dark Snow Project), has shared grubby and disturbing photos of the ice sheet:


He explained the photo: 

"12 August 2005, 8 PM local time, I took this photo from a helicopter flying over the ice sheet surface at ~1500 feet altitude. This is how much darker the Greenland ablation area [the summer melting area] is than a fresh snow surface that blankets it in wintertime. Along much of the southwestern ice sheet at the lowest 1000 m in elevation, impurities concentrate near the surface and produce this dark surface. Not all of the ice sheet is this dark, only the lower ~1/3 of the elevation profile of the ice sheet is. However, as melting increases on the ice sheet, so does the area exposed that is this dark."
-- Meltfactor.org

Eric Holthaus then published more of his photos on Slate.com


Photos: Eric Box, Dark Snow Project, published on Slate


The problem with either colourful or dirty snow is it messes with an important climate feedback loop: that of albedo.

Albedo is a measure of reflectivity, measured on a scale of 0 (all light is absorbed) to 1 (total reflection). Fresh snow has an albedo of up to 0.90, which is very high - that’s why it looks bright white. Snow's ability to reflect sunlight reduces the temperature at the surface and allows more snow to settle. You can see how this enables a virtuous circle: snow falls, greater albedo, cooler temperatures, more snow settles. Of course, the converse is also the case. Bare, darker land is warmer and snow doesn’t settle but melt, leaving the land still bare. On a smaller scale, the grain size of snow also increases microscopically as it warms up, too - giving it a rougher texture, and making it less reflective as well.

The impact of this increase in albedo is significant - Kristina Pistone’s 2014 paper estimates that declining Arctic albedo between 1979 and 2011 had a quarter as much impact on warming as increased carbon dioxide levels themselves. Another 2014 study led by Marie Dumont, a scientist at the French National Centre for Meteorological Research, found that the albedo values since 2009 had been even lower than before. Why? Colourful snow. Spectral analysis of the ice sheet indicated that the main darkening agent was reddish in colour, suggesting it was primarily dust - alongside some black carbon from industrial pollution, and microorganisms such as algae.

Feedback loop #2: “Now that seasonal snow cover in the Arctic is retreating earlier than before, bare soil is available earlier in the Spring for dust transport," said Dumont.

Feedback loop #3: The greater frequency of liquid water caused by rising temperatures provides a cosier environment for algae to grow - and the greater quantity of dust gives them more nutrients, as snacks. "Consequently, as dust content increases, microorganisms are likely to increase, too," Dumont notes. Shit.

It doesn't stop there.

Feedback loop #4: On 10-11 July 2012, the Greenland ice sheet saw an unprecedented event: 97% of the surface was melting, even at 80 degrees north and Summit, 3,200m above sea level. The cause: high pressure ridges in the upper atmosphere, exacerbated by the albedo effect from soot from forest fires in Siberia and North America darkening the ice. Research by Kaitlin Keegan of Dartmouth University argues that soot not only caused this melt event, but the previous widespread melt in 1889, too.

Of course, increasing temperatures will only lead to - you guessed it: more forest fires. Research released last month reports that “Current atmospheric models underestimate the dirtiness of Arctic air” (Sato et al., 2016)

*

So far this century, the ice sheet has lost an average of 238 gigatons of ice per year. This may be hard to imagine: I’d not encountered gigatons (10^9 tons) before writing this post. Try instead cubic kilometres.

Marie Dumont’s abstract notes, “In our snow model simulations, a decrease in the albedo of fresh snow by 0.01 leads to a surface mass loss of 27 Gt yr−1, which could induce an acceleration of Greenland’s mass loss twice as large as over the past two decades.”

Thus, the 2cm of global sea level rise I opened this newsletter with.

While only a few percent of the total rise we’re likely to see, I am amazed (and to be honest fascinated) that this can be driven by something so small - and apparently dull and innocuous - as dust.

I spent much of my time in Greenland gazing at the icebergs in the Jakobshavn ice fjord and trying to in some way comprehend these systems and these consequences in more than an abstract, intellectual sense. I’m not sure I got anywhere; I still don’t really know what that comprehension would look or feel like. Eco-theorist Timothy Morton would call these things ‘hyperobjects’, and say that the point is that we can’t properly perceive them at all.

I wrote about that bewilderment at greater length earlier today, on Medium.

Watching the ice in Jakobshavn ice fjord, Ilulissat, Greenland
 

NOTES, CITATIONS & ACKNOWLEDGEMENTS:

1. Dear new subscribers here from WIRED: hello! Welcome, and thank you for your patience waiting for this rather overdue newsletter. There are now 1,075 of you in total.

2. I have, as you can see, been travelling. In the last six weeks: Scotland, Amsterdam x2, Berlin and Iceland, as well as Greenland. Hence the delays writing. Greenland first got written up over on my Instagram, @hautepop - which I use like a blog, writing long captions. 

3. Then, earlier today I published an post on Medium, The Ice Fjord At The End Of The World. That essay is almost exactly like this newsletter, except not about dust. Take a look.

4. Citations are all inline this episode so no more footnotes, but can I just note that it's pretty cool to be citing three women as my main sources in the glaciology section? Kristina Pistone, Marie Dumont, and Kaitlin Keegan.

5. Research groups working on dusty snow include the Dark Snow Project, led by Dr Jason Box, and Black And Bloom, a consortium of UK scientists at Bristol, Leeds, Sheffield and Aberystwyth. It also turns out that Greenland ice sheet scientists are also really keen on tweeting (perhaps because there is not much else to do on an ice sheet once the measuring is done for the day). So follow along at @climate_ice and @glacier_albedo.

5a. I also ought to have cited the High Latitude Cold Climate Dust Network (@HLCCD) and the review paper Joanna E. Bullard et al. published this week about high latitude dust sources. Oops.

5b. The East Greenland Ice Core Project (@EGRIPcamp) is also pretty fun for their animated GIFs of the incredible way they built their camp out on the ice (hint: balloons...)

6. Next episode: ice cores (probably). I've also just finished reading Svetlana Alexievitch on Chernobyl, though, which suggests that's next-next - followed by 9/11, if I dare (though I have all sorts of questions about whether I am... allowed to? Whether I can do it justice. We'll see.)

7. Thank yous this episode first to Charlie Loyd, who alerted me to the existence of cryoconite earlier this year - and Wayne Chambliss, who came to Greenland. 

Until next time,
Jay