cryoconite

I heard this word spoken just this evening, in the documentary Chasing Ice, about the photographer James Balog and his Extreme Ice Survey, a project to photographically document shrinking glaciers. Interestingly, he puts the stress on the o, following a common model for dealing with polysyllabic Greek-derived words, but the dictionary pronunciation has stress directed by the morphology: cryoconite.

Very well, but what is it? You see the cry and you may think of tears, but you see the cryo and may think of cold things. And the conite – is it tears of contrition? Or is it some kind of cone? Or pneumoconiosis? Is the ite a signal that it is a mineral, or is it leading us into – or out of – nite?

The source parts tell one story, but the reality of it is more complex. The word comes from the Greek κρύος kruos ‘icy cold’ plus κόνις konis ‘dust, ashes’ plus that ite ending, also originally from Greek. So it’s cold dust. But it’s much more than that. And its significance has to do with heat.

Glaciers are dirty. Dust and soot and volcanic ash and so forth blows onto them from all over and settles. It is not distributed in a perfectly even pattern, of course; that would not be random (if all particles were evenly distributed, the distances between them would be highly consistent, not random at all). So there are little clumps here and there. And this dust and soot and so on is dark. So it absorbs heat from light. Which means that when the sun shines in the warmer weather, the ice under this dust melts, and soon the dust is sitting in a little pool of water. Which, being an indentation, draws more water and dust to it, and so it enlarges. Imagine a game of crokinole with the board slanted down towards the hole in the middle, and no pegs to bounce the little quoits out. Thus you have a cryoconite hole, which is a cylindrical hole with a diameter anywhere from less than a centimetre to more than a metre, filled with water (often deeper than the diameter) and with a layer of cryoconite on the bottom. Large areas of glaciers, especially closer to their leading edges, are a Swiss cheese of these holes, dotting them like the circles in the word cryconite.

So the cold dust creates warm tears as the glaciers melt into these little feedback cylinders. Ashes to ashes, dust to dust… But even if these holes are places where the glacier is dying, they are places where other things are living. Cryoconite is not dead and inert. It has bacteria in it, and sometimes algae too, and even insects, worms, crustaceans. Glaciers have whole ecosystems. They have millions of small ecosystems, each cryoconite its own little aquatic environment with pelagic and benthic zones, but taken all together they make up an ecosystem on the glacier that communicates from one part to another. In a delicious passage from “Possible interactions between bacterial diversity, microbial activity and supraglacial hydrology of cryoconite holes in Svalbard,” Arwyn Edwards et al. speak of findings that challenge “previous assumptions that glacial ecosystems are heterotrophic and dependent on an Aeolian flux of allochthonous organic matter” – in other words, previous assumptions that they rely on stuff blown in on the wind. Indeed, Edwards and colleagues find that there are complex contained ecosystems on glaciers, existing in these myriad cryoconite holes and communicating through melting and drainage.

So even as the glaciers disappear, we cannot simply sing “Dust in the Wind.” The fluid nature of existence means that as one thing goes another grows. As the glacier is less whole it is more hole, but those holes grow life, even as they further heat and kill the glacier. Once the glacier under and around them is gone, of course, the cryoconite will wash away too, the “cold dust” now a warm mud full of life on an ever-warming planet.