Antarctica is remote and unknown – but it may play a key role in the world’s future

Antarctica. Image: Getty.

Ever since the ancient Greeks speculated a continent must exist in the south polar regions to balance those in the north, Antarctica has been popularly described as remote and extreme. Over the past two centuries, these factors have combined to create, in the human psyche, an almost mythical land – an idea reinforced by tales of heroism and adventure from the Edwardian golden age of “heroic exploration” and pioneers such as Robert Falcon Scott, Roald Amundsen and Ernest Shackleton.

Recent research, however, is casting new light on the importance of the southernmost continent, overturning centuries of misunderstanding and highlighting the role of Antarctica in how our planet works and the role it may play in a future, warmer world.

What was once thought to be a largely unchanging mass of snow and ice is anything but. Antarctica holds a staggering amount of water. The three ice sheets that cover the continent contain around 70 per cent of our planet’s fresh water, all of which we now know to be vulnerable to warming air and oceans. If all the ice sheets were to melt, Antarctica would raise global sea levels by at least 56m.

Where, when, and how quickly they might melt is a major focus of research. No one is suggesting all the ice sheets will melt over the next century but, given their size, even small losses could have global repercussions. Possible scenarios are deeply concerning: in addition to rising sea levels, meltwater would slow down the world’s ocean circulation, while shifting wind belts may affect the climate in the southern hemisphere.

In 2014, NASA reported that several major Antarctic ice streams, which hold enough water to trigger the equivalent of a one-and-a-half metre sea level rise, are now irreversibly in retreat. With more than 150m people exposed to the threat of sea level rise and sea levels now rising at a faster rate globally than any time in the past 3,000 years, these are sobering statistics for island nations and coastal cities worldwide.

An immediate and acute threat

Recent storm surges following hurricanes have demonstrated that rising sea levels are a future threat for densely populated regions such as Florida and New York. Meanwhile the threat for low-lying islands in areas such as the Pacific is immediate and acute.

Much of the continent’s ice is slowly sliding towards the sea. Image: R. Bindschadler/Wikipedia Commons.

Multiple factors mean that the vulnerability to global sea level rise is geographically variable and unequal, while there are also regional differences in the extremity of sea level rise itself. At present, the consensus of the IPPC 2013 report suggests a rise of between 40 and 80cm over the next century, with Antarctica only contributing around 5cm of this. Recent projections, however, suggest that Antarctic contributions may be up to ten times higher.

Studies also suggest that in a world 1.5-2°C warmer than today we will be locked into millennia of irreversible sea level rise, due to the slow response time of the Antarctic ice sheets to atmospheric and ocean warming.

We may already be living in such a world. Recent evidence shows global temperatures are close to 1.5°C warmer than pre-industrial times and, after the COP23 meeting in Bonn in November, it is apparent that keeping temperature rise within 2°C is unlikely.

So we now need to reconsider future sea level projections given the potential global impact from Antarctica. Given that 93 per cent of the heat from anthropogenic global warming has gone into the ocean, and these warming ocean waters are now meeting the floating margins of the Antarctic ice sheet, the potential for rapid ice sheet melt in a 2°C world is high.


In polar regions, surface temperatures are projected to rise twice as fast as the global average, due to a phenomenon known as polar amplification. However, there is still hope to avoid this sword of Damocles, as studies suggest that a major reduction in greenhouse gases over the next decade would mean that irreversible sea level rise could be avoided. It is therefore crucial to reduce CO₂ levels now for the benefit of future generations, or adapt to a world in which more of our shorelines are significantly redrawn.

This is both a scientific and societal issue. We have choices: technological innovations are providing new ways to reduce CO₂ emissions, and offer the reality of a low-carbon future. This may help minimise sea level rise from Antarctica and make mitigation a viable possibility.

The ConversationGiven what rising sea levels could mean for human societies across the world, we must maintain our longstanding view of Antarctica as the most remote and isolated continent.

Chris Fogwill, Professor of Glaciology and Palaeoclimatology, Keele University; Chris Turney, Professor of Earth Sciences and Climate Change, UNSW, and Zoe Robinson, Reader in Physical Geography and Sustainability/Director of Education for Sustainability, Keele University.

This article was originally published on The Conversation. Read the original article.

 
 
 
 

In a world of autonomous vehicles, we’ll still need walking and cycling routes

A Surrey cycle path, 1936 style. Image: Getty.

The CEO of Sustrans on the limits of technology.

We are on the cusp of dramatic changes in the way we own, use and power our means of transportation. The mobility revolution is shifting from an “if” to a “where” and when”.

There are two different futures currently being imagined. First up, a heaven, of easy mobility as portrayed by autonomous vehicle (AV) manufacturers, with shared-use AV freeing up road space for public spaces and accidents reduced to near zero. Or alternatively, a hellish, dystopian pod-world, with single-occupancy pod-armadas leading to an irresistible demand for more roads, and with people cloistered away in walkways and tunnels; Bladerunner but with added trees.

Most likely, the reality will turn out to be somewhere in between, as cities and regions across the globe shape and accommodate innovation and experimentation.

But in the understandable rush for the benefits of automation we need to start with the end in mind. What type of places do we want to live in? How do we want to relate to each other? How do we want to be?

At Sustrans we want to see a society where the way we travel creates healthier places and happier lives for everyone – because without concerted effort we are going to end up with an unequal and inequitable distribution of the benefits and disbenefits from the mobility revolution. Fundamentally this is about space and power. The age-old question of who has access to space and how. And power tends to win.  

The wealthy will use AV’s and EV’s first – they already are – and the young and upwardly mobile will embrace micro mobility. But low-income, older and disabled residents could be left in the margins with old tech, no tech and no space.

We were founded in 1977, when off the back of the oil crises a group of engineers and radical thinkers pioneered the transformation of old railway lines into paths that everyone could walk and cycle on: old tech put to the service of even older tech. Back then the petrol-powered car was the future. Over 40 years on, the 16,575-mile National Cycle Network spans the length and breadth of the UK, crossing and connecting towns, cities and countryside, with over half of the population living within two miles of its routes.


Last year, more than 800 million trips were made on the Network. That’s almost half as many journeys made on the rail network, or 12 journeys for every person in the UK. These trips benefited the UK economy by £88m through reduced road congestion and contributed £2.5bn to local economies through leisure and tourism. Walking and cycling on the Network also prevented 630 early deaths and averted nearly 8,000 serious long-term health conditions.

These benefits would be much higher if the paths on the entire Network were separated from motor traffic; currently only one third of them are. Completing an entirely traffic-free walking and cycling network won’t be simple. So why do it?

In a world of micro-mobility, AVs and other disruptive technology, is the National Cycle Network still relevant?

Yes, absolutely. This is about more than just connecting places and enabling people to travel without a car. These paths connect people to one other. In times when almost a fifth of the UK population say they are always or often lonely, these paths are a vital asset. They provide free space for everyone to move around, to be, and spend time together. It’s the kind of space that keeps our country more human and humane.

No matter how clever the technological interface between autonomous vehicles and people, we will need dedicated space for the public to move under their own power, to walk and cycle, away from vehicles. As a civil society we will need to fight for this.

And for this reason, the creation of vehicle-free space – a network of walking and cycling paths for everyone is as important, and as radical, as it was 40-years ago.

Xavier Brice is CEO of the walking and cycling charity Sustrans. He spoke at the MOVE 2019 conference last week.