On 28 May 2008, a mass of ice about three miles across and a mile deep broke off the Ilulissat Glacier in western Greenland. Over the course of seventy-five minutes, huge chunks, many of them 1,000 metres or more from top to bottom, slid away and rolled over, thrusting their undersides hundreds of metres up out of the ocean as they did so. At one point, a dark shoulder of ice that resembled a whale of incredible size emerged groaning from the depths. Adam LeWinter and Jeff Orlowski, who captured the event on camera for the 2012 film Chasing Ice, suggest that ‘the only way you can put it into scale with human reference is if you imagine Manhattan, and all of a sudden those buildings start to rumble and quake, and peel off and fall over and roll around . . . this whole massive city just breaking apart in front of your eyes’. Even through the distancing effect of a YouTube clip, the enormity of sights and sounds so far outside everyday human experience is compelling, and it is hard not to watch and listen again and again.
Calving, as the shearing of icebergs from a glacier is known, is part of a natural cycle, but it seldom happens on the scale witnessed that day at Ilulissat. And it is only one small part of a broad set of changes that, whether humans are watching and listening or not, are now taking place faster and at a larger scale than at any time in at least several million years. The melt rate of the world’s glaciers caused by human emissions of greenhouse gases, already well above the background rate by the year 2000, has doubled in the last twenty years. Many of the glaciers that remain are likely to shrink and disappear in the coming decades.
The effects of climate change upon the glacial landscape often takes a quieter and more subtle form than the Ilulissat crash. When the writer Robert Macfarlane visited the Knud Rasmussen Glacier in Greenland, he heard a low rumble, rising in volume as he approached, of ice melt pouring into a moulin (that is, a deep shaft) which presaged an encounter with what he describes as ‘the most beautiful and frightening space into which I have ever looked’. Matthew Burtner, composer of the album Glacier Music, describes glaciers as songful beings. ‘They express their state through an intricate sonic outpouring which is the result of their melting [that generates] a rich complex of interwoven voices, threading together into a symphonic tapestry of noise.’ When they reach the sea, glacier fragments continue to make noises: small chunks of floating ice are called growlers because they sometimes growl like animals as gas trapped inside escapes from them.
There can be a strange beauty in some of the changes taking place. Listening through special equipment to a melting iceberg off the Antarctic Peninsula, the journalist Jonathan Watts hears the sound of air bubbles escaping up through the deep interior and is ‘transported – not, it seemed, below the ocean, but into a vast cavern, where it sounded as if water was cascading from a high ceiling, each drip echoing through the emptiness’. Permafrost can also make almost musical sounds as it thaws. ‘It’s like an orchestral piece,’ says the geographer Julian Merton of a crater subsiding in the ground in Yakutia in the Russian Far East. ‘In the summer, when the head wall is thawing quickly, you hear the constant trickle of water, like first violins. And then you have these massive chunks of permafrost, up to half a ton, that fall to the bottom with a big thud. That’s the percussion.’
The impacts of climate change on life on Earth are also apparent in the changing sounds of forests and other ecosystems. For twenty years at the same time each year, the musician and acoustic ecologist Bernie Krause recorded the sounds of birds, mammals, amphibians and insects at Sugarloaf Park in California. When short clips from each year are played back to back, a dramatic diminution and fragmentation is clear. Elsewhere, researchers have found that a degraded landscape doesn’t necessarily become more quiet. In places such as the Ecuadorian Amazon, disrupted ecosystems sometimes actually get louder within certain ranges of pitch, at least for a while, as incoming creatures compete and cross-talk to fill ‘holes’ in the soundscape.
Acoustic ecologists also monitor changes that take place outside the scope of human hearing. When insects and bats decline in numbers, whether as a result of large-scale pesticide use, changes caused by global heating or other factors, the ultrasonic soundscape empties out too. On tropical coral reefs, a ‘dawn chorus’ of fish and other animals falls silent as extreme heat events kill the majority of the corals on which they depend.
The phrase ‘climate breakdown’ has achieved some currency in recent years. It can give the impression of a world falling apart and ceasing to work. But this gives at best a partial sense of what is happening. Yes, rapid climate change threatens the viability of many species and ecosystems and, without quick action to reduce emissions, is likely to degrade or endanger much of human and non-human life. Barring a transition without precedent, man-made climate change could bring near-unliveable conditions to billions of people. But the climate itself is not ‘breaking down’. Rather, as the late climate scientist Wally Broecker put it, ‘the climate system is an angry beast and we are poking it with sticks’. With the net addition of energy in the form of heat it is, if anything, speeding up.
The sounds of climate change are not just those of diminution and disappearance, but also those of more powerful hurricanes, heavier rainfall events and more destructive floods, and larger and fiercer fires. They may prove to be the sounds of more human anguish and suffering as well because, other things being equal, a hotter world is likely to be a more violent one. Climate change may cause even more harm by increasing the likelihood of war than it does by increasing the likelihood of extreme weather.
‘It’s been a while since we have been able to turn to the natural world for reassurance, to map the arc of an individual life against the eternal cycle of the seasons,’ observes the poet Kathleen Jamie; ‘the feeling of being imperilled is now constant.’ In these circumstances, one of the most precious sounds is your voice. ‘The most important thing,’ says the atmospheric scientist Katharine Hayhoe, ‘is to talk about climate change.’ Every fraction of a degree of global heating matters, every year matters, every action matters, and we need to discuss how we can improve our lives and those of others while lessening our adverse impacts and finding more ways to put our words into action.
From A Book of Noises, published by Granta Books
Caspar Henderson is the author of The Book of Barely Imagined Beings, A New Map of Wonders and A Book of Noises. A writer, editor and journalist, he lives in Oxford
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