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Regular updates of geographical inspiration.

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Tweets by TeamGeography

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How the World Cup 2014 would play out if 32 countries were competing in things other than soccer.

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Glaciers are melting so much they are changing the shape of the Earth's crust

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Glaciers are melting so much they are changing the shape of the Earth's crust

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Glaciers are melting so much that they are causing the Earth's crust to change shape.

And now scientists have used this effect to discover an alarming new phenomenon that is speeding up the rate at which ice is pouring into the sea.

A team of Nasa scientists used measurements of "solid Earth deformation" to study the Rink Glacier in Greenland as it melted rapidly in the hot summers of 2010 and 2012.

What they found was that the "intense" melting of ice produced a 'solitary wave' in the glacier that pushed it more quickly towards the sea, which Nasa likened to a "warmed freezer pop[sicle] sliding out of its plastic casing".

Writing in the journal Geophysical Research Letters, the scientists said "the wave through Rink Glacier is enormous in terms of its mass transport".

Traveling at up to 12km per month, the 2012 wave alone was responsible for moving 6.7 billion tons of ice into the sea - compared to the average annual total of about 11 billion tons in the early 2000s.

The scientists, from Nasa's Jet Propulsion Laboratory in Pasadena, California, said changes in the Earth's crust had not been used before to assess glaciers.

The research represented a "breakthrough" because it showed how powerful this technique was but also because it had revealed the wave effect, they said.

Miles of Antarctic ice are collapsing into the sea

"The technique is effectively using the measurement of the deformed solid Earth elastic response as a filter that uniquely responds to neighbouring glacier mass changes," they said.

It is thought the wave began after meltwater cut channels through the glacier and drained down to the bottom.

In a statement, Nasa said the exact process was unclear, but the current theory to explain why the glacier "moved so quickly" went something like this: "The huge volume of water lubricated the base of the glacier, allowing it to move more rapidly, and softened the side margins where the flowing glacier meets rock or stationary ice.

"These changes allowed the ice to slide downstream so fast that ice farther inland couldn't keep up."

One of the Nasa researchers, Dr Erik Ivins said solitary waves were likely to become a bigger factor in the future.

"Intense melting such as we saw in 2010 and 2012 is without precedent, but it represents the kind of behaviour that we might expect in the future in a warming climate," he said.

"We're seeing an evolving system."

10 photographs to show to anyone who doesn't believe in climate change

The changes in the Earth's crust were monitoring by more than 50 GPS stations on the bedrock in Greenland.

These are not currently being maintained by any agency and the Nasa team were carrying out the research partly to see if there was any reason to keep them.

"Boy, did we find one," Dr Ivins said.

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Glaciers are melting so much they are changing the shape of the Earth's crust

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Glaciers are melting so much that they are causing the Earth's crust to change shape. And now scientists have used this effect to discover an alarming new phenomenon that is speeding up the rate at which ice is pouring into the sea.

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The deadly diseases being released as ice thaws

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The deadly diseases being released as ice thaws

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The deadly diseases being released by climate change

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Previously undiscovered "giant viruses" have been found trapped in the arctic ice, and known killers such as Anthrax are being released as ice melts.

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A massive climate change study is canceled ... because of climate change

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A massive climate change study is canceled ... because of climate change

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A team of scientists from the University of Manitoba and four other schools were in the middle of the first leg of a four-year study of how climate change is affecting the areas around the Hudson Bay, the university said in statement. The study, named BaySys, started last month, and the scientists were traveling on the Canadian Research Icebreaker CCGS Amundsen.

But because of warmer temperatures in the Arctic, hazardous sea ice is traveling farther south than usual. The Amundsen, which is part of the Canadian Coast Guard fleet, has been diverted several times because its ice-breaking capabilities have been needed to help out in rescue efforts along Newfoundland's northeast coast. All of the delays and concerns about safety forced the cancellation of the study's first leg.

"Considering the severe ice conditions and the increasing demand for search and rescue operations and ice escort, we decided to cancel the BaySys mission," said Dr. David Barber, expedition chief scientist and BaySys scientific lead. "A second week of delay meant our research objectives just could not be safely achieved. The challenge for us all was that the marine ice hazards were exceedingly difficult for the maritime industry, the (Canadian Coast Guard) and science."

Barber and his team confirmed that a large portion of the sea ice they were seeing off Newfoundland's coast was indeed from the Arctic.

"Climate-related changes in Arctic sea ice not only reduce its extent and thickness but also increase its mobility meaning that ice conditions are likely to become more variable and severe conditions such as these will occur more often," Barber said.

The ironic events won't scrap the entire project though. The study's second leg, due to take off early next month, is still on, said fellow researcher Dr. Louis Fortier, the scientific director of the Amundsen and ArcticNet's science programs.

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canadian climate change study cancelled because of climate change - cnn

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A massive climate change study is canceled ... because of climate change

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A team of scientists from the University of Manitoba and four other schools were in the middle of the first leg of a four-year study of how climate change is affecting the areas around the Hudson Bay, the university said in statement.

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Europe’s terror threat is real. But its cities are much safer than you think

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Europe’s terror threat is real. But its cities are much safer than you think

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Europe's terror threat is real. But its cities are much safer than you think

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While the threat of terrorism in Europe is genuine, it is dramatically lower than just about anywhere else in the world.

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Infographic: Where Does Commuting Cost the Most?

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This graphic shows the ten cities worldwide where commuting via public transport costs the most.

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Sharp rise in UK mortality rate may be due to austerity measures

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Sharp rise in UK mortality rate may be due to austerity measures

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By the end of 2015 it had emerged that the UK had experienced the largest annual spike in mortality rates for nearly 50 years. The magnitude of the increase in mortality rates was shocking - we estimated that during the period from July 2014 to June 2015 there had been an additional 39,074 deaths across England and Wales compared with the previous year. This represents an increase of 7.4% of all deaths in the 2014-15 period.

Mortality rates went up for most age groups, but were particularly concentrated among the elderly. Mortality rates rose by 11.8% and 18.2% for males and females respectively aged 90 and above, 9.2% and 11.2% respectively for people aged 85-89, and 5.7% and 9.3% respectively for people aged 80-84. These rises in old-age mortality occurred everywhere: in richer and poorer areas, in urban and rural districts, and in the north and south.

This is a troubling find. Throughout the 20th and 21st centuries, we have grown accustomed to mortality rates declining for all age groups year-on-year, and life expectancy continually improving. These improvements in population health were due to medical discoveries, better sanitation and improved quality of life. However, July 2014 through to early 2017 represents a clear reversal in these trends. The extent of the 2014-15 increase was not large enough for the UK's life expectancy to decline for the period, but if these increases were to be maintained for a longer period then life expectancy may begin to decline.

The consistent geography to these increases suggests that any cause must be something that has affected everyone in the UK. The most obvious explanation for a factor that we have all experienced has been the UK government's roll-out of austerity measures.

Cutbacks are killing us

It is plausible that the impacts of cutbacks to public services are beginning to materialise. There have been pronounced increases in NHS trusts with deficits since 2014-15, as well as funding crises in adult social care. Under-investment in these key services could be combining to create blockages in patients being discharged, which is both stressful for individuals who want to be discharged, as well as stopping new beds becoming free for those who need them. When the elderly become frail, a "triple-lock" on their pensions (that is, pensions rise annually by either the same as average earnings, inflation, or 2.5% depending on which is higher) offers little comfort if they are completely reliant on social services that are also being cut back.

However, the UK has been experiencing austerity since 2009 and if austerity is the cause then why have we not seen its effects sooner? We have already consistently been seeing the negative effects of austerity prior to 2015 on a range of health outcomes including suicides, mental health, hunger and well-being. The knock-on effect to overall mortality rates - especially in the elderly - may have taken a little longer to materialise.

Of course, there are alternative explanations, but they are not as convincing as the austerity argument. Mortality rates jump around from year to year, but they typically fall (with the rate of the fall varying) and the mortality rates we observed in 2015 have persisted throughout 2016 and into 2017. The last spike in mortality rates comparable in size (in 1968) was due to a flu epidemic, however, the flu strain over the period we analysed was described by Public Health England as "moderate". It may also be that we are seeing the effects on an ageing population, although if this were the case then we would expect a gradual change particularly as the post-war baby boomers have not reached the age ranges we focus on (80 years of age and over). Each of these factors may have contributed to what was witnessed, but none are clearly the primary cause.

One limitation to the austerity argument is that mortality increases occurred regardless of geography, despite the fact that austerity policies resulted in cutbacks being more commonplace in poorer areas. It may be that the extent of cutbacks matters less, rather that cutbacks have happened everywhere.

No matter the cause, the magnitude of the increases in 2015 which have been sustained throughout 2016 and into early 2017 raise troubling questions. If life for the elderly is getting worse, is this what we should expect for our own lives? Is the golden age of declining mortality rates and increasing life expectancy over? If austerity is the cause, then what should be the response? Clearly investing in the NHS and adult social care to address their under-funding would help alleviate their issues and is the most obvious solution. However, if cutbacks continue elsewhere, then mortality rates may continue to remain just as high.

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Sharp rise in UK mortality rate may be due to austerity measures

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By the end of 2015 it had emerged that the UK had experienced the largest annual spike in mortality rates for nearly 50 years. The magnitude of the increase in mortality rates was shocking - we estimated that during the period from July 2014 to June 2015 there had been an additional 39,074 deaths across England and Wales compared with the previous year.

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From Infinity War to Okja: why overpopulation is cinema's crisis du jour

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From Infinity War to Okja: why overpopulation is cinema's crisis du jour

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SLIGHT INFINITY WAR SPOILERS

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There are 7,622,000,000 people in the world today, and not all of them are superheroes in the Marvel Cinematic Universe. But even though rising population figures are good for box-office receipts, it is a real-world trend that has sparked alarm and controversy for decades. And, while it is still a somewhat peripheral concern in contemporary politics - unlike, say, climate change - overpopulation has nevertheless become the crisis du jour in modern blockbuster filmmaking. As a movie-plot issue, population crisis exists between a plausible future and an imagined dystopia, offering Hollywood a force of moral nuance that exceeds the brute power of pure evil's wrecking balls.

The makers of Avengers: Infinity War (2018) actually grappled with a double-pronged population crisis in the latest instalment in the Marvel's Avengers series. First, they had to ram dozens of standalone superheroes, from Doctor Strange to Black Panther, into a tolerable length of film, and second, only anxiety over population growth could provide sufficient moral complexity for the franchise's big boss, Thanos.

"It's a simple calculus," Thanos declares with near Shakespearean panache, "This universe has finite resources ... if life is left unchecked, life will cease to exist. It needs correcting." Thanos is using the same reasoning as Bertrand Zobrist from Inferno (2016), adapted from the Dan Brown novel. "The darkest places in hell are reserved for those who refuse to act in times of crisis. We have created our own hell on Earth," he says from beyond the grave, having released a virus to deplete global populations, before taking his own life. "Expect the current population to be culled by half. The survivors will witness horrors unknown to this planet but I want them to know why, that this was our doing and this is our salvation. Now is the time." Zobrist, like Thanos, is almost an anti-hero who accepts the necessity of doing bad in order to do good.

The trend is not just present in comic-book movies, nor simply as an explanation of untrammelled evil. Helga Luthersdottir, an academic specialising in superhero studies, says that the focus for plotlines is now "competition for limited resources", with some movies depicting the aftermath of unchecked population growth.

In Steven Spielberg's 2018 film Ready Player One, the inhabitants of a metropolis of slum housing escape into a VR landscape called the OASIS, where they can live with a freedom denied them in their cramped reality. Alexander Payne's Downsizing, meanwhile, released last year takes overpopulation and climate change as jumping-off points for a social parable in which Matt Damon is shrunk to the size of a Ken doll to cut the size of his carbon footprint. With Okja (2017), a sinister multinational food corporation struggles to breed genetically engineered superpigs to feed an ever-growing population. Films such as these display specific contemporary anxieties about population growth but build, cinematically, on a foundation laid when the underground proletariat toiled to provide for the high-rise aristocracy in Fritz Lang's 1927 film Metropolis.

Hollywood's interest in population crises reflects a publishing trend. Back in 2013, in the space of a month, two books were published with near identical titles and subjects: Stephen Emmott's bite-sized, apocalyptic, vision, Ten Billion, and Danny Dorling's longer, more optimistic, Population 10 Billion. Both posed the question: when the global population count hits 10 billion, as projections suggest it will around 2050, can we sustain life on Earth at current levels of consumption?

Emmott takes rather the same view as Thanos and Zobrist (though without encouraging genocide), considering waste reduction and technological solutions as equally unlikely. When I ask him whether he feels his concerns about population growth have resonated in pop culture, he is unconvinced. "While these science-fiction films view the consequences of population growth in different, but uniformly dystopian, ways they all share a common thread that is anything but science fiction, it is science fact," he says. "Since [Ten Billion] was published in 2013, it is absolutely clear that this is a message that no one wants to hear. So instead we are happy to continue to treat it as science fiction."

For Dorling, a more optimistic attitude about the future is reflected in a more political diagnosis of moviemaking trends. "It is probably not a coincidence that immigration has risen as a political issue in the United States, and in the UK before the Brexit result deflated that bubble of fear," he says. "This especially applies to Hollywood. I would be amazed if Bollywood uses this trope much, but I don't get out enough to watch enough films!"

Indeed, you can read immigration anxiety into older films with population disasters, such as Soylent Green (1973) where, in a Swiftian twist, the excess population is euthanised and turned into nutritious wafers, and Children of Men (2006), which inverts these visions by showing a future where resource scarcity is caused by sterility, rather than reproduction. As Dorling observes, "At some point we should begin to get low fertility apocalyptic films, when a director realises that average human fertility is falling rapidly and not set to stop at two babies per couple but below that after 2100 (if not before 2100)." As Luthersdottir says: "Popular culture reflects that which is popular - and as such it will always reflect that which is the perceived reality ... rather than attempting to enlighten us about actual reality."

Regardless of its salience, the issue of rising population is likely to reappear in the fourth Avengers movie. When you have enacted a plan that murders half the population of the universe, the industrial sabotage and family revenge plotlines of earlier Marvel movies start to feel rather small fry. Thanos's personal mystique and the logic of his position have been maintained into the next stage of the film. When Doctor Strange asks him what he would do after killing half of all living things, he responds: "I finally rest, and watch the sun rise on a grateful universe."
Topics

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From Infinity War to Okja: why overpopulation is cinema's crisis du jour

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There are 7,622,000,000 people in the world today, and not all of them are superheroes in the Marvel Cinematic Universe. But even though rising population figures are good for box-office receipts, it is a real-world trend that has sparked alarm and controversy for decades.

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'Feel good' factor not CO2 boosts global forest expansion

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'Feel good' factor not CO2 boosts global forest expansion

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Forests are increasing around the world because of rising incomes and an improved sense of national wellbeing say researchers.

The authors refute the idea that increasing levels of CO2 in the atmosphere are the key cause of the spread of trees.

As countries become better off, farmers focus on good quality soils and abandon marginal lands, the authors say.

As a result, trees are able to rapidly reforest these deserted areas.

The study highlights the fact that between 1990 and 2015 forest growing stock increased annually by 1.31% in high income countries and by 0.5% in middle income nations, while falling by 0.72% in 22 low income countries.

Several global climate models have attributed this change to what's termed CO2 fertilisation - where higher levels of carbon dioxide in the atmosphere boost the growing abilities of plants and trees.

But the authors say that this greening process has been going on since the 1800s in Western Europe when CO2 in the atmosphere was just starting to rise.

"When people are feeling good, it benefits forests," Prof Pekka Kauppi from the University of Helsinki, the paper's co-author, told BBC News.

"It is not just income. When a society works properly then deforestation automatically seems to disappear, and society reaches a sort of a balance with the forests. Once a country has a decent life, they do not deplete forests they want to protect them. When livelihoods come from other sources not subsistence farming then marginal lands are abandoned and people just leave the forests to grow back."

Other parts of the world have started to increase forest cover in relation to their development and not just levels of CO2 the professor says. Europe, the US, Japan and New Zealand have all increased cover over the past century while over the past 50 years China and Chile have also seen forests increase.

Between 1990 and 2015 some 13 tropical countries have transitioned from places with net forest losses to net forest gains.

"Weather observations confirm indisputably that global temperatures are rising together with atmospheric CO2 levels," said co-author Prof Antti Lipponen of the Finnish Meteorological Institute.

"However, the study shows that, over more than a century, changes in forest growing stock around the world have been virtually unrelated to those trends."

The authors say that development encourages market economies which tend to concentrate farming onto the best lands with farmers abandoning marginal lands and often moving to the cities. Better technology and higher yields also tend to reduce the need to clear new agricultural lands and usually, as incomes rise, other fuel sources other than wood become available.

Another factor is that as countries get wealthier, they tend to import more products based on natural resources rather than manufacture them.

India is an "amazing example" says Prof Kauppi, having increased forest cover between 1970 and 2010 while at the same time, seeing its population double.

"If food can be grown on smaller areas of the very best lands, then marginal lands can be left aside and India is one of the regions of the world where agriculture was very low yielding earlier on but with the green revolution and an excellent climate for plant growth they have managed to feed the population relatively well."

While development is critical the authors expressed concern about the future of Africa, with a majority of the 55 countries there have not reported moving from forest losses to forest gains. Losses are also being experienced in Nigeria, Brazil and Indonesia.

Brunei is only wealthy country the researchers found with decreasing forest cover.

The study has been published in the journal PLOS One.

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'Feel good' factor boosts global forests

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Forests are increasing around the world because of rising incomes and an improved sense of national wellbeing say researchers. The authors refute the idea that increasing levels of CO2 in the atmosphere are the key cause of the spread of trees. As countries become better off, farmers focus on good quality soils and abandon marginal lands, the authors say.

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Icebergs and empty pools: Five things Cape Town's Day Zero taught us

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Icebergs and empty pools: Five things Cape Town's Day Zero taught us

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When Cape Town revealed it was fast hurtling towards the moment it would become the first city on earth to run out of water earlier this year, it caught the world's attention.

Initial predictions said the taps in this South African city of four million people should have run dry by April.

But despite the odds appearing stacked against it, the dams never fell to 13.5% - the level needed to reach "Day Zero", which has now been pushed back to next year at the earliest.

The rains have finally arrived, and Cape Town appears to have pulled itself back from the brink - for now.

So, what lessons have been learned?

Icebergs could be the answer

At times like this, it is probably always worth thinking outside the box.

But when Nick Sloane - a South African salvage captain known for righting the Costa Concordia - announced he could solve the issue by dragging a 100 million tonne iceberg north from the Antarctic, more than a few eyebrows were raised.

But, Capt Sloane assured the BBC's Newsday programme, it is completely possible.

"At any one time there are thousands of icebergs which have broken off drifting around the Southern Ocean," he said.

"Most of the icebergs are pushed south by the Agulhas current. We going to try and guide the iceberg into a different current: the Benguela current."

The current, he explained, is cold so the iceberg would be preserved - and crucially would be taken some 1,200 nautical miles north to near Cape Town, where it should - in theory - come to a halt on the sea bed.

But why go to all this effort? Well, one of these icebergs would provide enough water for a third of Cape Town's residents for an entire year.

Cape Town's deputy mayor Ian Neilson still needs to be convinced though - especially because moving icebergs thousands of miles is not without risk, and definitely not cheap.

"The questions are: 'What is the price, how long is it going to take?'" he told the BBC. "So a really strong case would need to be made."

And anyway, the city already has its own plans in place to supplement its dams.

"Certainly, we are driving projects around ground water, water reuse and desalination, and until we see something better that's what we will do," he explained.

Which seems to suggest that another idea, mooted more than a decade ago, to drive water 2,500 miles from the Congo River to Cape Town is probably not going to happen.

Which is good, because that water is also being eyed up as a possible solution to Africa's vanishing lake.

You can live on 50 litres of water a day...

The crisis really caught the world's attention after it was announced citizens would only be allowed to live on 50 litres of water a day.

But Capetonians quickly adapted. Ninety-second showers, unflushed loos and dirty cars are matters of pride in Cape Town homes, while some restaurants have completely shut off their bathroom taps, forcing customers to opt for hand sanitizer instead, and many public swimming pools are empty.

And it has worked.

"We have got our overall consumption down by 50%," said Mr Neilson. "It could not have been achieved by just a small number of people. Very clearly, there has been a change in people's approach to water."

Of course, there are places still boasting perfectly manicured, green lawns. But generally these all come with a sign on the wall declaring - somewhat defensively - "borehole water", meaning they are not using the mains supply.

Borehole digging, in turn, has become a new source of income for Cape Town's entrepreneurs, with adverts offering the service on lampposts across the city.

And if you still suspect your neighbour of not doing their part, there is a handy interactive map which shows exactly how much each street is using.

... the poorest residents already do

When Day Zero was first announced, there was a bit of finger-pointing towards the city's informal settlements, where it was claimed by some that taps ran almost non-stop.

Quite simply, Mr Neilson said, this was not true. According to South Africa's News24, even before the drought, homes in Cape Town's informal settlements used just 40 litres per day.

"Informal settlements use less than 4% of the water. That's not the place where the problem is," Mr Neilson said.

"The big usage was what takes place behind big walls."

It may not be a good idea to tell tourists

Day Zero may have been enough to frighten Capetonians into action, but it had an unfortunate side effect: it also scared the tourists.

Cape Town and the wider Western Cape welcome more than 1.6m international visitors a year - not to mention the 2.1m South Africans who holiday in the region.

But at the height of the crisis, an informal study of 18 businesses by the province's tourism agency, Wesgro, found revenue for January and February had fallen by up to 20% year-on-year.

Which, when 300,000 people rely on tourism for their wage across the Western Cape, was not good news.

But Wesgro responded, encouraging tourists to become part of the solution, and promoting sustainable, "water-wise tourism".

They also sent out the message that Cape Town was still open for business - and it looks like it is working: August and September are seeing year-on-year increases in bookings of 4% and 5% respectively.

And finally: Prevention is better than cure

Cape Town, Mr Nielson admitted, was taken by surprise by the three-year drought which led to the dire warnings.

"The rainfall that we have had has fallen off the charts, and it happened instantly - overnight," he says.

"Change can happen and hit you far more quickly and more dramatically than you anticipated. So how do you prepare for that?

"If you depend on just one source of water supply only, you need to change and diversify. You must start putting things into place before this disaster happens so you already have this resilience built in."

Cape Town should now be able to build up its own ability to withstand another drought like this one, not only with its water plans, but also by putting in new legislation to ensure homes are more water-efficient in the future.

But more than that, it is hoped people will stick to the changes they have made - albeit eventually in a less draconian way.

After all, following the last big drought it took a decade for water consumption to reach its previous levels, Mr Neilson said.

And what's more, saving water has now become a badge of honour for the city's residents.

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How an iceberg could ease Cape Town's water crisis

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When Cape Town revealed it was fast hurtling towards the moment it would become the first city on earth to run out of water earlier this year, it caught the world's attention. Initial predictions said the taps in this South African city of four million people should have run dry by April.

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Store footfall in 'unprecedented' decline

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Store footfall in 'unprecedented' decline

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Poor weather and a squeeze on spending caused a slide in the number of people visiting shops last month.

Footfall fell by 3.3% last month according to the British Retail Consortium (BRC) and Springboard.

That was lower than the 6% decline in March, but was still an "unprecedented" 4.8% decline over the two-month period.

Diane Wehrle, of Springboard, said: "Not since the depths of recession in 2009 has footfall over March and April declined to such a degree."

"Even then the drop was less severe at minus 3.8%."

New data also showed that the town centre vacancy rate rose to 9.2%, with all areas of the UK, except Greater London, reporting an increase.

BRC chief Helen Dickinson said changing shopping habits and tough trading were weighing on high streets.

As well as "a wet start to April", she said a shift in shopping habits, along with a "highly challenging" business environment, was having a significant impact on high streets: "In April nearly 1 in 10 shops in town centres was vacant."

There were 4,083 new store openings in 2017, the lowest since 2010, but 5,855 outlets closed, meaning a total of 1,772 shops disappeared, according to the Local Data Company.

'Parlous state'

The BRC and Springboard found that although footfall improved in the second two weeks of the month, people were choosing to spend their money on leisure activities such as going to restaurants or pubs rather than shopping.

Ms Wehrle added: "The parlous state of retail trading is highlighted by the fact that footfall post-5pm recovered in the last two weeks of the month, rising by 5.9%, whilst daytime footfall dropped by 0.1%.

"So it is clear that retail trading is doubly challenged by a thrifty consumer, in concert with a continuing predisposition towards leisure rather than retail spend."

UK wage growth has trailed inflation for more than a year.

Last month, official figures for the three months to February showed that average wages rose by 2.8%, still below the 2.9% inflation rate using the consumer prices index (CPI) measure.

The latest threat to the High Street came on Saturday when it emerged that the owner of Poundworld had put the discount retailer up for sale, the BBC understands.

Private equity firm TPG had been looking at closing about 100 of Poundworld's 355 stores as part of a restructuring plan.

However, that process has been put on hold after receiving expressions of interest in the chain.

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Store footfall in 'unprecedented' decline

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Poor weather and a squeeze on spending caused a slide in the number of people visiting shops last month. Footfall fell by 3.3% last month according to the British Retail Consortium (BRC) and Springboard. That was lower than the 6% decline in March, but was still an "unprecedented" 4.8% decline over the two-month period.

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The UK towns and cities with the highest and lowest wages

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The UK towns and cities with the highest and lowest wages

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Whether you are a security guard, lawyer, or IT worker, wages vary hugely across the UK. But where are the towns and cities that offer the best wages?

Workers in 15 of the country's largest towns and cities - defined here as built-up urban areas with 135,000 or more people - earn more than the average weekly wage of £539.

In contrast, workers in the 48 other towns and cities of this size earned less than the national average.

The reasons reveal a great deal about the way people live and work.

The UK's highest paid towns and cities

There are no prizes for guessing that salaries are highest in London, where the average weekly wage is £727.

Nor that the capital is followed by neighbouring towns and cities.

The next six highest earning places are all in the South East, with average wages of £600 or more in Reading, Crawley, Milton Keynes, Cambridge, Slough and Oxford.

That's largely because they are all home to significant numbers of highly skilled workers who can command good wages. It's also due to their proximity to London, which helps these places attract high-paying companies.

But it's not just the South East that is doing well, with wages of almost £600 per week in Edinburgh, Aberdeen, and Derby, thanks mainly to their successful finance, oil and manufacturing industries.

The UK's lowest paid towns and cities

At the other end of the table, the lowest pay is, perhaps surprisingly, found in another place close to London.

At £413 per week, average pay in Southend is just over half that in the capital.

This helps explain why so many people commute from Southend into London, with one in five of its working population making the journey.

The number of people earning their money in London means that the average salary among Southend residents is £144 higher than it is for those who actually work in the town.

However, Southend is one of the few places in the South East near the bottom of the pay-scale. Worthing is the only other town from the region in the bottom 10.

More broadly, there is a definite north-south divide when it comes to wages, with most - but not all - of the lowest paid towns and cities in Yorkshire and the North West of England.

Huddersfield has the second lowest wage of any large town or city, with its workers earning £424 per week on average. It is followed by Birkenhead and Wigan, where workers are paid £428 and £436 respectively.

Belfast (£514) and Cardiff (£505) also fall under the UK average for wages, despite being the capitals of Northern Ireland and Wales respectively.

Why do wages differ between cities?

The main reason why some towns and cities offer lower average wages is simple: they are home to fewer high paying occupations.

For example, more than 12% of jobs in Reading and Milton Keynes are in high-income senior management roles, which pay an average £915 per week in the UK. Only 6% of jobs in Stoke and Hull are in this category, with just over 8% in Glasgow and Swansea.

Even within cities there can be great differences - workers in Tower Hamlets, in east London, are paid an average of £952 per week, compared with £518 for those working in Sutton, on the outskirts. Again, this reflects the number of senior managers in each area.

Skills levels are also a big issue in most places with below average wages.

For example, Wigan, Barnsley and Doncaster - all of which feature in the bottom 15 - have some of the lowest shares of residents educated to degree level.

Swansea and Belfast have some of the highest levels of residents who have no formal qualifications whatsoever.

Same job, different wage

There are also big gaps between what people get paid for doing the same kinds of jobs in different towns and cities.

Workers in jobs classed by the Office for National Statistics as "elementary occupations" - such as cleaners and security guards - are paid less in Plymouth and Warrington (£205 per week) than anywhere else in the country. In Slough, people in equivalent roles are paid about twice as much.

Those in "sales and customer service occupations", such as sales assistants and call centre staff, are paid least in Wigan (£207 per week) and most in Crawley (£354).

The same disparities can be seen among senior managers and directors, with the lowest salaries in Southend (£615 per week) and the highest in London (£1,208 per week).

There are a number of reasons why.

Differences in the cost of living is one, with housing in places such as London, Cambridge and Reading being much more expensive than elsewhere in the country.

To attract the workers they need, businesses have to offer higher wages, especially to people at the lower end of the salary scale - which pushes up the average wage.

A notable exception to this pattern is Derby, which despite being in the top 10 for wages (£595 a week) has relatively low house prices.

But a bigger factor is the value people working in the same jobs in different places bring to the economy.

For example, in the business services sector - which includes lawyers and architects - the average output of a worker in London, in monetary terms, is more than double that in Southend.

That's because lawyers in London are more likely to be undertaking work for which they can charge bigger fees.

Think corporate lawyers working in London's financial services, compared with local housing conveyancing solicitors in Southend.

Similarly, the value of the work done by someone in the information and communications sector (which includes computer programmers and telephone engineers) in Reading is twice that of someone working in the same sector in Wakefield.

This reflects the fact that Reading is home to many high skilled, complex roles in computing giants such as Microsoft and Hewlett Packard.

How can struggling cities boost average wages?

To improve wages in poorly paid cities, the big challenge is to make more high quality jobs - those that contribute more to the economy - available to people living in them

This is one reason why politicians and commentators have been so worried about productivity in recent years.

Only by increasing the amount the average worker produces will we be able to see sustained rises in pay.

The lack of such opportunities in struggling towns and cities has implications for how attractive they are for people to live in.

Over the past 10 years those towns and cities that have the highest paying jobs have seen the largest growth in the working age population - people aged between 16 and 64.

Places such as London, Edinburgh and Milton Keynes have been able to attract significant numbers of new residents because of the jobs and wages they offer.

But Burnley and Birkenhead have seen their working age populations fall, reflecting lower wages and the relative lack of career opportunities.

Creating more jobs in these places is only part of the answer to improving living standards.

Raising wages will be critical in turning around the fortunes of both struggling towns and cities and the people living in and around them.

Highest and lowest wages in UK's largest towns and cities*

London: £727

Reading: £655

Crawley: £633

Milton Keynes: £619

Cambridge: £609

Slough: £606

Oxford: £600

Edinburgh: £598

Aberdeen: £597

Derby: £595

Aldershot: £588

Southampton: £579

Luton: £571

Swindon: £560

Bristol: £547

National Average: £539

Leeds: £533

Coventry: £532

Birmingham: £527

Glasgow: £526

Gloucester: £526

Portsmouth: £520

Belfast: £514

Liverpool: £512

Manchester: £512

Warrington: £510

Northampton: £508

Ipswich: £506

Cardiff: £505

Dundee: £503

Bournemouth: £503

Basildon: £501

Newcastle: £501

York: £501

Blackpool: £500

Exeter: £499

Peterborough: £497

Telford: £497

Brighton: £496

Chatham: £494

Blackburn: £488

Nottingham: £486

Sunderland: £484

Wakefield: £483

Leicester: £480

Preston: £480

Middlesbrough: £477

Sheffield: £474

Newport: £473

Mansfield: £472

Plymouth: £467

Hull: £466

Swansea: £464

Burnley: £459

Stoke: £455

Bradford: £455

Worthing: £455

Barnsley: £453

Norwich: £450

Doncaster: £447

Wigan: £436

Birkenhead: £428

Huddersfield: £424

Southend: £413

*The Centre for Cities data covers built-up urban areas with a population of 135,000 or more
About this piece
This analysis piece was commissioned by the BBC from an expert working for an outside organisation.

Andrew Carter is chief executive and Paul Swinney is head of research and policy at the Centre for Cities, which describes itself as working to understand how and why economic growth and change takes place in the UK's cities.

Edited by Duncan Walker

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The UK cities with the highest and lowest wages

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Whether you are a security guard, lawyer, or IT worker, wages vary hugely across the UK. But where are the towns and cities that offer the best wages? Workers in 15 of the country's largest towns and cities - defined here as built-up urban areas with 135,000 or more people - earn more than the average weekly wage of £539.

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Marylebone Road and Hyde Park Corner, both in central London, have the most polluted postcodes in Britain, says a new study on air quality.

The data comes from a project to map concentrations of nitrogen dioxide (NO2) across the country.

However, the results also show that large parts of Britain have relatively clean air.

Diesel vehicles are a key source of NO2 gas, which has been linked to respiratory disease.

While this study only concentrates on NO2 pollution, scientists advise that high concentrations of NO2 are generally a good indication that other pollutant types may also be present.
You can see what air quality is like in your area by entering your postcode in the search below. The data represents an average for 2016 and does not include Northern Ireland. If you cannot view the postcode search, please click here to reload the page.
Although dirty air doesn't kill people directly, it's estimated to contribute to shortening the lives of 40,000 people a year in the UK. Pollution is thought to undermine the health of people with heart or lung problems.

A new analysis by the company EarthSense shows NO2 concentrations in 100x100m squares across the UK. The company's technical director, Prof Roland Leigh, says it is the most detailed model yet for assessing air quality in Britain.

"By focussing it down we can really isolate the hotspots of poor air quality, and better target our solutions."

Prof Leigh says it's important to be aware of bad pollution levels where you live, or near schools or your route to work, but that no areas in Britain are bad enough that people should avoid exercising outside.

"Air quality is actually getting better in Britain, and we are in a better state than a large number of countries - particularly across Asia.

Keep away from the busiest roads - pollution concentrates around the heaviest traffic

Use side roads - these are cleaner because there is so much less traffic

Watch out for hotspots of dirty air - engines are often left running in stationary traffic. This can create "urban canyons" of pollution, particularly around traffic lights, so stand back after pushing the button before crossing the road

When walking up a hill always stick to the side where traffic is flowing down the hill, away from the brunt of the fumes. This will always be the cleaner alternative

Basic face-masks are not worth the hassle - these trap dust but little else, while heavy-duty versions are cumbersome. Scientists recommend avoiding busy roads instead

"In Britain, it's always better to be outside exercising than inside avoiding pollution, even in the worst areas."

Five ways to avoid pollution

In the study, each area is rated on a scale from 1, least polluted, to 6, most polluted. More than four in five postcodes in Great Britain fall into the least polluted category (1).

The scale is worked out based on a probability that each area will break the annual legal limit for NO2. Areas fall foul if they average more than 40 micrograms of NO2 per cubic metre.

Fewer than 1% of postcodes are rated either 4 or 5, and no postcodes in Great Britain fall into the highest category - six - for areas that average over 100 micrograms of NO2 per cubic metre.

Three-quarters of the postcodes with the worst ratings are in London. Those outside the capital include other built-up areas as well as otherwise rural locations near motorways.

The company has largely based its analysis on traffic emissions, the dominant source of NO2 in the UK.

In many big cities, such as London, safe limits on harmful particulates and nitrogen oxides, including NO2, are regularly breached.
Updated 8 February 2018: This article has been updated to clarify that the EarthSense study on air quality concentrates only on NO2 pollution. Scientists advise that high concentrations of NO2 are generally a good indication that other pollutant types may also be present. Further work is being carried out to cover particulate matter. In the UK, you can see more on this story and how to combat air pollution on Postcode search produced by Rosie Gollancz, Sumi Senthinathan, Ransome Mpini, Shilpa Saraf, Joe Reed and Daniel Dunford. The company behind the data have produced responses to some FAQs about it here. Fighting for Air on BBC Two at 21:00 on Wednesday 10 January and afterwards on iPlayer.
In the last few years, the campaign group ClientEarth has won a number of rulings against the UK government over air pollution. These legal challenges forced ministers to draw up plans to tackle the problem and meet EU targets on NO2.

However, a recent study in the journal Nature Geoscience suggested that targets for reducing NO2 pollution could be achieved more quickly than the government expects. This was because government projections did not take into account that as cars age, they produce less of the harmful gas.

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Marylebone Road and Hyde Park Corner, both in central London, have the most polluted postcodes in Britain, says a new study on air quality. The data comes from a project to map concentrations of nitrogen dioxide (NO2) across the country. However, the results also show that large parts of Britain have relatively clean air.

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UK's most polluted towns and cities revealed

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UK's most polluted towns and cities revealed

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Some 47 towns and cities across the UK are at or have exceeded air pollution limits set by the World Health Organization, its new report has found.

The WHO data shows 32 areas have fine particle air pollution levels above 10 micrograms per cubic metre, with the remaining 15 at that limit.

Areas that exceeded the level include London and Manchester, with the Welsh steelworks town Port Talbot the worst.

Dirty air can cause debilitating diseases and hasten death.

The figures on air pollution, contained in the WHO's global report, found Port Talbot had fine particle air pollution levels recorded at 18 micrograms per cubic metre, with the next most polluted UK areas being Scunthorpe and Salford on 15 micrograms.

Fine air particle pollution is particularly bad for us, penetrating deep into the lungs and cardiovascular system, causing diseases including stroke, heart disease, lung cancer and respiratory infections, the WHO says.

It estimates that globally 7 million people die each year from exposure to such pollution, with most of these deaths being in low and middle-income countries, mainly in Asia and Africa.

However, while many UK towns had air pollution recorded at or above the WHO's recommended limit, in a number of places the levels are falling.

In London, for example, levels fell from 17 to 11 micrograms from 2013 to 2015, while in the same period it fell from 17 micrograms to 12 in Sheffield.

Worldwide, the WHO's report estimated that 9 out of 10 people breathe air containing high levels of pollutants.

Simon Gillespie, chief executive of the British Heart Foundation, said the UK still had "a long way to go in the fight against air pollution".

"The UK government needs to show leadership by adopting WHO air quality guidelines into national legislation and in doing so, help to protect the nation's heart and circulatory health."

The 32 UK places (and Gibraltar) that exceeded the limit of 10 micrograms per cubic metre:

Port Talbot: 18 micrograms per cubic metre

Scunthorpe: 15

Salford: 15

Gibraltar: 14* (Taken in 2013)

Thurrock: 14

Manchester: 13

Swansea: 13

Gillingham: 13

Carlisle: 12

Chepstow: 12

Leeds: 12

Leicester: 12

Liverpool: 12

Grays: 12

Eccles: 12

Nottingham: 12

Plymouth: 12

York: 12

Prestonpans: 12

Royal Leamington Spa: 12

Sandy: 12

Sheffield: 12

Stoke-On-Trent: 12

London:11

Coventry: 11

Hull: 11

Londonderry: 11

Middlesbrough: 11

Norwich: 11

Southend-On-Sea: 11

Stockton-On-Tees: 11

Storrington: 11

Wigan: 11

The 15 towns that are at the limit:

Armagh:10

Birmingham: 10

Brighton: 10

Bristol: 10

Cardiff: 10

Eastbourne: 10

Harlington: 10

Newcastle: 10

Newport: 10

Oxford: 10

Portsmouth: 10

Preston: 10

Saltash: 10

Southampton: 10

Stanford-Le-Hope: 10

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UK's most polluted towns and cities revealed

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Some 47 towns and cities across the UK are at or have exceeded air pollution limits set by the World Health Organization, its new report has found. The WHO data shows 32 areas have fine particle air pollution levels above 10 micrograms per cubic metre, with the remaining 15 at that limit.

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Where are the UK's youngest and oldest cities?

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Where are the UK's youngest and oldest cities?

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Cities are often thought of as places for the young, but the reality is that many have an ageing population. What difference does the age of a city's residents make?

Over the past two decades, the average age of a UK resident has risen by two years, to 40. Within 30 years, one in four people is expected to be aged 65 and over.

But the picture in cities is more complex.

At 38, the average city dweller is younger. Cities are home to 62% of people aged 18-34, but only 46% of those aged 65 and over.

Despite this, the populations of most UK cities are growing older, raising big questions about what that means for their development, and for meeting the future needs of residents.

The Centre for Cities looks at built-up urban areas with 135,000 or more people, rather than just officially recognised cities. This allows us to compare changes across the UK's largest centres of population.

The UK's youngest cities

The UK city with the youngest population is Slough, with an average age of 33.9 and only one in 10 people aged 65 and over.

It is followed by Oxford (34.4) and Luton (35.1). The average age in London, the sixth youngest city, is 36.5.

Slough and Luton have particularly high shares of under-18s, partly because they have the highest birth rates of all UK cities - 16.6 and 17.9 births for every 1,000 residents, compared to the British average of 11.8. This has been partly driven by their young migrant populations.

Oxford has the highest share of people aged 18-24, reflecting the city's large university population.

The UK's oldest cities

In contrast, Blackpool has the oldest population of any UK city, with an average age of 43.2.

It is followed by fellow coastal cities of Worthing (43), Bournemouth (42.8) and Southend (42.2).

These cities have high shares of people who are at retirement age.

More than one in five residents of each city was 65 and over in 2016 - apparently reflecting the pull of the seaside for people who have finished their working lives.

Change over the past 20 years

Over the past 20 years, younger people have increasingly chosen to live in urban areas, while the share of older residents in cities has fallen.

In 1996, 58% of people aged 18-34 lived in cities, but this had risen to 62% by 2016.

In contrast, the share of people aged 65 or older in cities fell from 51% to 46% during this period.

Despite these patterns, the average age of the population in most cities has changed in line with that of the population of the UK as a whole.

Only six cities - Brighton, Exeter, Oxford, Cambridge, Coventry and Slough - saw a drop in the average age of their population, mostly as a result of expanding student populations and Slough's high birth rate.

The populations of most cities grew older.

Sunderland's population aged most, with the average resident being just under four years older (41) in 2016 than in 1996. It is closely followed by the urban areas around Aldershot, Warrington and Middlesbrough.

There are two main groups among the cities which age faster than others.

The first is made up of those which have struggled economically in recent decades - for example, Middlesbrough and Wigan.

They have seen a decline in people aged between 25 and 40 - most probably because of young people moving away in search of job opportunities.

The second group is made up of new towns such as Milton Keynes and Warrington.

It was mostly young people who moved to new towns in the decades after they were created.

However, those once-young residents have got older - and the average age of these cities has increased.

Milton Keynes, for example, had a large population of 20 and 30-somethings in 1996, but they are now approaching middle age.

What does this mean for cities?

A younger population can bring advantages such as attracting businesses, who will have a larger pool of working age residents to draw from.

However, cities need to provide opportunities for young people to start and build careers, as well as cultural amenities, schools and affordable housing.

Among those cities which have been getting younger, Oxford, Cambridge and Brighton have large shares of high-skilled, high-paying jobs, and all offer good access to quality schools.

But housing is an issue in these cities, which are among the least affordable places in the UK.

Cities with older populations have different benefits and challenges.

Older people of working age tend to be more productive and can command higher wages because of their experience and skills.

This in turn increases disposable income which can be spent in shops, bars and restaurants.

But it's also clear that places which have older residents face greater demands in terms of health and social care provision.

Another challenge, which faces all cities, is that they do not have great flexibility over how they spend money.

For example, much of the money that cities receive from central government is allocated for specific issues - like potholes and schools.

It could be that some would benefit from being able to prioritise social care, or affordable family homes, for example.

As their populations continue to diverge, cities are likely to become increasingly focused on the needs of their own residents.

It is clear that some will be growing old faster than others.

Youngest and oldest cities

Slough 33.9

Oxford 34.4

Luton 35.1

Cambridge 35.4

Coventry 36.2

London 36.5

Bradford 36.7

Cardiff 36.7

Blackburn 36.9

Leicester 36.9

Milton Keynes 37

Peterborough 37

Crawley 37.2

Northampton 37.5

Birmingham 37.6

Hull 37.6

Leeds 37.6

Southampton 37.6

Bristol 37.7

Exeter 37.7

Manchester 37.8

Reading 37.8

Derby 38

Belfast 38.1

Chatham 38.2

Liverpool 38.2

Nottingham 38.2

Brighton 38.5

Ipswich 38.6

Edinburgh 38.7

Gloucester 38.8

Aberdeen 38.9

Sheffield38.9

Swindon38.9

Telford 39

Huddersfield 39.1

Basildon39.3

Plymouth 39.4

Aldershot 39.5

Glasgow39.5

Burnley 39.6

Dundee 39.6

Stoke 39.6

York 39.6

Newcastle 39.8

Preston 39.9

Middlesbrough 40

Newport 40

Portsmouth 40.3

Warrington 40.4

Doncaster 40.5

Wigan 40.6

Norwich 40.7

Mansfield 40.8

Wakefield 40.8

Barnsley 40.9

Sunderland 41

Swansea 41

Birkenhead 42.1

Southend 42.2

Bournemouth 42.8

Worthing 43

Blackpool 43.2

Source: NOMIS, mid-year population estimates

About this piece
This analysis piece was commissioned by the BBC from an expert working for an outside organisation.

Andrew Carter is Chief Executive and Paul Swinney is Head of Research and Policy at the Centre for Cities, which describes itself as working to understand how and why economic growth and change takes place in the UK's cities.

Edited by Duncan Walker

# data[].attributes.attachment_link.title
Where are the UK's youngest and oldest city populations?

# data[].attributes.attachment_link.description
Cities are often thought of as places for the young, but the reality is that many have an ageing population. What difference does the age of a city's residents make? Over the past two decades, the average age of a UK resident has risen by two years, to 40.

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The constant roar of traffic, incessant construction noise, piercing sirens, honking horns, shrieking loudspeakers - noise in cities is clearly a nuisance.

But it's also a danger. The World Health Organisation (WHO) has described noise pollution as an underestimated threat that can cause hearing loss, cardiovascular problems, cognitive impairment, stress and depression. Some experts go further: they believe exposure to environmental noise could be slowly killing us.

"Noise pollution causes hypertension, diabetes, obesity, heart attacks, strokes and death," says Dr Daniel Fink, chairman of the Quiet Coalition, a community of health and legal professionals concerned with the adverse impacts of environmental noise.

Noise pollution is often cited as one of the main factors in the reduced quality of life in large, 24-hour cities like New York (where more than 200,000 noise complaints were recorded in 2016). It causes stress, which has its own adverse effects on health.

While the impact of noise on mental health has not been studied extensively, research has shown that "strong noise annoyance is associated with a twofold higher prevalence of depression and anxiety in the general population".

A recent study by experts at the American College of Cardiology linked noise pollution to increased cardiovascular problems (high blood pressure, heart attacks, stroke, coronary heart disease) through the body's stress mediated response - resulting in the release of the stress hormone cortisol, which in turn damages blood vessels.

At a conference on noise organised by the European commission in April 2017, noise was regarded as "the silent killer", with potentially severe consequences for our physical and mental health. And yet its impacts remain unreported and underestimated.

Dr Eoin King, assistant professor of acoustics and author of the book Environmental Noise Pollution, calls noise the ignored pollutant. "Environmental noise still continues to be poorly understood by practitioners, policymakers and the general public," he says.

Though there is no set threshold to establish risk, anything above 60 decibels can increase risk for heart disease

Dr Thomas Münzel

Most worrying, says King, is the impact on children. "Studies considering the effect that noise may have on children have found that tasks such as reading, attention span, problem-solving and memory appear to be most affected by exposure to noise."

The issue is compounded by debate over how much noise it is safe to be exposed to. In its Make Listening Safe guide, WHO states that 85 decibels is considered the highest safe exposure level, up to a maximum of eight hours. However, others - Fink among them - argue this is still too loud.

A car measures 70 decibels, a jackhammer 100, and a plane taking off 120, according to the WHO. "Though there is no set threshold to establish risk, we do know that anything above 60 decibels can increase risk for heart disease," Dr Thomas Münzel, from the Mainz University Medical Centre, has said.

A recent report by the BBC found that parts of the London Underground were "loud enough to damage people's hearing", with noise levels greater than 105 decibels on many lines. The report stated that some were "so loud they would require hearing protection if they were workplaces".

Guangzhou has been ranked as having the worst levels of noise pollution in the world Photograph: ChinaFotoPress via Getty Images

Concerned about increased risk of hearing loss in cities, last year Mimi Hearing Technologies created a World Hearing Index to draw attention to the issue. With the results of hearing tests of 200,000 of their users worldwide and data on noise pollution from WHO and Sintef, a Norwegian research organisation, the index plotted levels of noise pollution and hearing loss in 50 cities.

The study found that, on average, a person living in the loudest cities has hearing loss equivalent to that of someone 10-20 years older. Overall the results showed a 64% correlation between hearing loss and noise pollution.

Guangzhou, China, ranked as having the worst levels of noise pollution in the world, followed by Cairo, Paris, Beijing and Delhi. Of the 50 cities, Zurich was found to have the least noise pollution.

Participants in Delhi recorded the highest average hearing loss - equivalent to someone 19.34 years older than them. Vienna had the lowest hearing loss - but still, on average, that of someone 10.59 years older.

"We were able to collect quite a unique hearing data warehouse on hearing abilities across countries and continents," says Henrik Matthies, managing director of Mimi Hearing Technologies. "There is an obvious known correlation between being exposed to noise and decreased hearing ability.

"However, mapping this correlation to cities helped us to get the message out, sparking a debate about noise pollution and hearing in megacities like Hong Kong and Delhi."

But what can be done about it?

"The EU are probably the world leaders at setting out a process to tackle noise pollution," says King. In 2002, it issued an environmental noise directive that requires member states to map noise exposure in urban areas holding upwards of 100,000 people, to develop noise abatement action plans in these areas and to preserve quiet areas.

If we could make planes, trains and ​​cars quieter ​we would solve a lot of our problems.

Dr Eoin King

Action plans usually incorporate a variety of measures such as traffic management strategies, promoting light rail systems and electric buses, reduced speed limits, introducing noise barriers and improved planning processes.

But good intentions only go so far. "The problem is that there is no real enforcement associated with these action plans," says King. "Until there is more of a political will to drive planning decision related to noise, I don't think much will change."

With road traffic by far the largest source of noise pollution in Europe, affecting an estimated 100 million Europeans, concepts like Paris's car-free day could have an impact. For one day every month in the French capital, 30% of the city becomes off limits to vehicles. The project has seen sound levels in the city centre drop by half.

"The most effective way to control noise is at the source. If we could make planes, trains and cars quieter we would solve a lot of our problems," says King. "If all vehicles in a city street were electric, noise would be significantly reduced."

Increasingly citizens can also do their bit to monitor noise pollution in cities by transforming their smartphones into sound level meters.

The NoiseTube app, developed by researchers at the Free University of Brussels in Belgium, enables users to record where and at what times decibel levels are highest to produce a detailed "noise map" of the city. Councils can use the data to target noise pollution more effectively, using sound absorbent materials such as foam and fibreglass precisely where they are needed most.

King says there are many such projects looking to harness the potential of big data in the fight against noise - "for example, noise complaint data, or social media chatter related to noise, to better assess public sentiments towards soundscapes. There is a lot going on - which I suppose gives us some hope."
Follow Guardian Cities on Twitter, Facebook and Instagram to join the discussion, and explore our archive here

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The constant roar of traffic, incessant construction noise, piercing sirens, honking horns, shrieking loudspeakers - noise in cities is clearly a nuisance. But it's also a danger. The World Health Organisation (WHO) has described noise pollution as an underestimated threat that can cause hearing loss, cardiovascular problems, cognitive impairment, stress and depression.