Study: further melting of Antarctic glacier half the size of Germany is 'irreversible'

An international group of researchers has found that the largest glacier in West Antarctica is "retreating inland" faster than ever.

In this week’s New Statesman I wrote about the misadventures of the MV Akademik Shokalskiy, the research vessel trapped in ice off the shore of Antarctica, and why “one localised incident does not disprove the vast body of evidence demonstrating that the world is heating up, decade by decade”.

There’s been an increase in the amount of ice in the sea around Antarctica, which - compared to the continually-shrinking ice in the Arctic - reassures sceptics that they were right about this climate change brouhaha all along. But, of course, that’s not the case at all. The ice on the land (the ice that, when it melts, raises sea levels) is decreasing, and while sea ice is increasing, that’s probably because the run-off from the land is diluting the sea, raising its freezing point.

Categorising that melt is difficult, as, compared to the Arctic, Antarctica is much more massive and much less well-documented landmass with a wider range of climates. As an example, a new study in Nature Climate Science has found that the Pine Island Glacier, in West Antarctica, has found that it may have entered an “irreversible” melting period where the amount of water it unloads into the ocean increases five-fold.

The 175,000km2 glacier - that’s about half as big as Germany - is responsible for draining a quarter of the West Antarctica ice sheet by itself, and regularly calves off huge icebergs into the Southern Ocean. The Natural Environment Research Council’s (NERC) British Antarctic Survey has found that it’s “retreating inland”, a sign that its melt is increasing. It’s bad news. Very bad.

Here’s the NERC’s news site, Planet Earth Online:

'At the Pine Island Glacier we have seen that not only is more ice flowing from the glacier into the ocean, but it's also flowing faster across the grounding line - the boundary between the grounded ice and the floating ice. We also can see this boundary is migrating further inland,' says Dr G Hilmar Gudmundsson from NERC's British Antarctic Survey, a researcher on the project.

All the models agreed that the Pine Island Glacier has become unstable, and will continue to retreat for tens of kilometres.

'The Pine Island Glacier shows the biggest changes in this area at the moment, but if it is unstable it may have implications for the entire West Antarctic Ice Sheet,' says Gudmundsson. 'Currently we see around two millimetres of sea level rise a year, and the Pine Island Glacier retreat could contribute an additional 3.5 - 5 millimeters in the next twenty years, so it would lead to a considerable increase from this area alone. But the potential is much larger.'

A doomsday scenario, where the entire West Antarctica ice sheet melted away, would cause a sea level rise of five metres. That’s not what’s being forecast here, but the level of melt is illustrative of a crucial threat to the world from climate change - even if we were to stop producing gases that cause the net warming effect today, many of their effects are now locked-in and inevitable.

A 30-mile-long iceberg calving off Pine Island Glacier, in 2011. (Photo: NASA)

Ian Steadman is a staff science and technology writer at the New Statesman. He is on Twitter as @iansteadman.

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The deafening killer - why noise will be the next great pollution scandal

A growing body of evidence shows that noise can have serious health impacts too. 

Our cities are being poisoned by a toxin that surrounds us day and night. It eats away at our brains, hurts our hearts, clutches at our sleep, and gnaws at the quality of our daily lives.

Hardly a silent killer, it gets short shrift compared to the well-publicised terrors of air pollution and sugars food. It is the dull, thumping, stultifying drum-beat of perpetual noise.

The score that accompanies city life is brutal and constant. It disrupts the everyday: The coffee break ruined by the screech of a line of double decker buses braking at the lights. The lawyer’s conference call broken by drilling as she makes her way to the office. The writer’s struggle to find a quiet corner to pen his latest article.

For city-dwellers, it’s all-consuming and impossible to avoid. Construction, traffic, the whirring of machinery, the neighbour’s stereo. Even at home, the beeps and buzzes made by washing machines, fridges, and phones all serve to distract and unsettle.

But the never-ending noisiness of city life is far more than a problem of aesthetics. A growing body of evidence shows that noise can have serious health impacts too. Recent studies have linked noise pollution to hearing loss, sleep deprivation, hypertension, heart disease, brain development, and even increased risk of dementia.

One research team compared families living on different stories of the same building in Manhattan to isolate the impact of noise on health and education. They found children in lower, noisier floors were worse at reading than their higher-up peers, an effect that was most pronounced for children who had lived in the building for longest.

Those studies have been replicated for the impact of aircraft noise with similar results. Not only does noise cause higher blood pressure and worsens quality of sleep, it also stymies pupils trying to concentrate in class.

As with many forms of pollution, the poorest are typically the hardest hit. The worst-off in any city often live by busy roads in poorly-insulated houses or flats, cheek by jowl with packed-in neighbours.

The US Department of Transport recently mapped road and aircraft noise across the United States. Predictably, the loudest areas overlapped with some of the country’s most deprived. Those included the south side of Atlanta and the lowest-income areas of LA and Seattle.

Yet as noise pollution grows in line with road and air traffic and rising urban density, public policy has turned a blind eye.

Council noise response services, formally a 24-hour defence against neighbourly disputes, have fallen victim to local government cuts. Decisions on airport expansion and road development pay scant regard to their audible impact. Political platforms remain silent on the loudest poison.

This is odd at a time when we have never had more tools at our disposal to deal with the issue. Electric Vehicles are practically noise-less, yet noise rarely features in the arguments for their adoption. Just replacing today’s bus fleet would transform city centres; doing the same for taxis and trucks would amount to a revolution.

Vehicles are just the start. Millions were spent on a programme of “Warm Homes”; what about “Quiet Homes”? How did we value the noise impact in the decision to build a third runway at Heathrow, and how do we compensate people now that it’s going ahead?

Construction is a major driver of decibels. Should builders compensate “noise victims” for over-drilling? Or could regulation push equipment manufacturers to find new ways to dampen the sound of their kit?

Of course, none of this addresses the noise pollution we impose on ourselves. The bars and clubs we choose to visit or the music we stick in our ears. Whether pumping dance tracks in spin classes or indie rock in trendy coffee shops, people’s desire to compensate for bad noise out there by playing louder noise in here is hard to control for.

The Clean Air Act of 1956 heralded a new era of city life, one where smog and grime gave way to clear skies and clearer lungs. That fight still goes on today.

But some day, we will turn our attention to our clogged-up airwaves. The decibels will fall. #Twitter will give way to twitter. And every now and again, as we step from our homes into city life, we may just hear the sweetest sound of all. Silence.

Adam Swersky is a councillor in Harrow and is cabinet member for finance. He writes in a personal capacity.