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5 october 2020
"Most people have never seen a glacier" (11), says Peter Knight, and I haven't seen most things that most people have seen. But glaciers, yes. I have seen them in Montana, in the Alps, and in Iceland. From the air, I have often seen the enormous ice cap, that covers Greenland – one of the two largest glaciers extant (the other covers Antarctica), and thus one whose thaw would inundate many coastal human habitats.
As Knight points out in Glacier, mine may be the last generation to see glaciers at all. Well, I suppose it will take a very long time for the Antarctic ice sheet to melt. But to see circum-human glaciers like those in North American national parks, or the Alpine crossroads of Europe. Those may vanish in this century. Perhaps tourists will follow the retreat of the Antarctic or Greenland ice caps, or the glaciers of the Himalayas. Going to view such attractions will become easier as they get less icy.
And there may be an equilibrium to such things. The current retreat of the world's glaciers is doubtless being hastened by human activity. But as glaciers retreat, they leave rock and soil exposed, which may in turn absorb the carbon dioxide we are pumping into the atmosphere, which would make things cooler again and the glaciers grow. Such highly sensitive and unpredictable feedback loops, says Knight, make opining about glacier futures somewhat parlous.
We do know something about the past of glaciers, though less than we'd like. Glaciology, as pioneered by Louis Agassiz in the 19th century, is a masterpiece of inference from the traces that glaciers leave, directly and indirectly – and the traces within them, observable from cores drilled deep into their ice. Glaciers also have a robust photographical record, now going back a century-and-a-half or more. Even pre-photographic paintings and drawings can often be compared to the current extent of glaciers to show how much they've retreated in the last two or three hundred years.
Knight is especially good on glaciers in arts and culture. From Romantic mountainscapes to postmodern creations like Katie Paterson's recordings of the sounds of glaciers (which she presses into phonograph records made of ice), glaciers have captured the imagination of artists who are drawn to nature and the sublime. Artists with an appreciation for long stretches of time are especially drawn to glaciers. Knight says that water falling into river systems reaches the ocean, on average, within ten days. Snow falling on a glacier takes 10,000 years to make the same trip. Ephemeral as they may be in geological time, and evanescent as they are right now, glaciers, on a human scale are about waiting things out. "Earth is made into art," says Knight of the work of glaciers (152). I thought of Slartibartfast's pride in the fjords of Norway, in Douglas Adams' Hitchhiker's Guide to the Galaxy.
But artistic though they may be, glaciers can carry crucial information about the environment, and thus about our chances of being around much longer to appreciate their aesthetics. Knight says that traces of Roman lead smelting persist in glacial strata from 2,000 years ago. Even then, humans could lay a big toxic footprint over a wide stretch of the globe. We are lucky, Knight says, that plans to stuff nuclear waste into glaciers fell through in the more cavalier 1970s. Otherwise we might have fused an even grimmer reminder of ourselves into the ice. As it is, we are cheerfully dusting today's glaciers with all sorts of pollution – and we will only erase these tell-tales if we melt the remaining glaciers altogether.
Knight, Peter G. Glacier: Nature and Culture. London: Reaktion, 2019.