China is using mobile phone signals to map its ghost cities

Some of the ghost cities identified by Baidu researchers. Image: Baidu.

You'd think it'd be relatively hard to mislay a city. Cities are, by definition, very large things: losing one sounds like it should be much more challenging than losing, say, your car keys, or even your entire car. 

But in China, there are entire cities which go relatively unaccounted for. This is the result of a combination of fast development, low regulation, and the fact that many Chinese cities are still practically empty. 

This is why it's pretty hard to get a figure for just how many "ghost cities" – cities that exist, but lack residents – there are in China. Most of these cities have some residents, making "ghost" a relative, and pretty hard to define, term. 

So Baidu (basically, China's Google) decided to work it out. The researchers behind a new study, "Ghost Cities: Analysis Based on Positioning Data in China", used location data from users' phones, plus mapping and building location data, to find areas with high volume of buildings, but a low density of people. The researchers also tried to discount vacant areas that were empty because of tourism: apartments only filled in high tourism season, for example. 

Here are some areas of vacant housing they found in nine different cities: 

Overall, the researchers say they found over 50 ghost cities, though they only revealed around 20 in the report, so as not to adversely effect the real estate market in the rest. (No comment.) 


As the researchers admit in their conclusion, this isn't a conclusive study: it relies, first and foremost, on the idea that "Baidu users" are a good proxy for "people", and that areas with no Baidu activity are empty. Yet as they note, arrogantly and probably accurately:

With the ubiquity of smart mobile phones, Baidu users occupy the most proportion of the whole population. 

This does seem to be one of the more accurate surveys of China's ghost cities produced so far, even if the researchers won't release all the details. That could mean greater accountability for the development firms who toss up concrete blocks and then fail to fill them. 

 
 
 
 

Barnet council has decided a name for its new mainline station. Exciting!

Artist's impression of the new Brent Cross. Image: Hammerson.

I’ve ranted before about the horror of naming stations after the lines that they’re served by (screw you, City Thameslink). So, keeping things in perspective as ever, I’ve been quietly dreading the opening of the proposed new station in north London which has been going by the name of Brent Cross Thameslink.

I’ve been cheered, then, by the news that station wouldn’t be called that at all, but will instead go by the much better name Brent Cross West. It’s hardly the cancellation of Brexit, I’ll grant, but in 2017 I’ll take my relief wherever I can find it.

Some background on this. When the Brent Cross shopping centre opened besides the A406 North Circular Road in 1976, it was only the third large shopping mall to arrive in Britain, and the first in London. (The Elephant & Castle one was earlier, but smaller.) Four decades later, though, it’s decidedly titchy compared to newer, shinier malls such as those thrown up by Westfield – so for some years now, its owners, Hammerson, have wanted to extend the place.

That, through the vagaries of the planning process, got folded into a much bigger regeneration scheme, known as Brent Cross Cricklewood (because, basically, it extends that far). A new bigger shopping centre will be connected, via a green bridge over the A406, to another site to the south. There you’ll find a whole new town centre, 200 more shops, four parks, 4m square feet of offices space and 7,500 homes.

This is all obviously tremendously exciting, if you’re into shops and homes and offices and not into depressing, car-based industrial wastelands, which is what the area largely consists of at the moment.

The Brent Cross site. Image: Google.

One element of the new development is the new station, which’ll sit between Hendon and Cricklewood on the Thameslink route. New stations are almost as exciting as new shops/homes/offices, so on balance I'm pro.

What I’ve not been pro is the name. For a long time, the proposed station has been colloquially referred to as Brent Cross Thameslink, which annoys me for two reasons:

1) Route names make rubbish modifiers because what if the route name changes? And:

2) It’s confusing, because it’s nearly a mile from Brent Cross tube station. West Hampstead Thameslink (euch), by contrast, is right next to West Hampstead tube.

Various other names have been proposed for the station. In one newsletter, it was Brent Cross Parkway; on Wikipedia, it’s currently Brent Cross South, apparently through confusion about the name of the new town centre development.

This week, though, Barnet council quietly confirmed it’d be Brent Cross West:

Whilst the marketing and branding of BXS needs to be developed further, all parties agree that the station name should build upon the Brent Cross identity already established. Given the station is located to the west of Brent Cross, it is considered that the station should be named Brent Cross West. Network Rail have confirmed that this name is acceptable for operational purposes. Consequently, the Committee is asked to approve that the new station be named Brent Cross West.

Where the new station will appear on the map, marked by a silly red arrow. Image: TfL.

That will introduce another irritating anomaly to the map, giving the impression that the existing Brent Cross station is somehow more central than the new one, when in fact they’re either side of the development. And so:

Consideration has also been given as to whether to pursue a name change for the tube station from “Brent Cross” to “Brent Cross East”.

Which would sort of make sense, wouldn’t it? But alas:

However owing to the very high cost of changing maps and signage London-wide this is not currently being pursued.

This is probably for the best. Only a handful of tube stations have been renamed since 1950: the last was Shepherd’s Bush Market, which was until 2008 was simply Shepherd's Bush, despite being quite a long way from the Shepherd's Bush station on the Central line. That, to me, suggests that one of the two Bethnal Green stations might be a more plausible candidate for an early rename.


At any rate: it seems unlikely that TfL will be renaming its Brent Cross station to encourage more people to use the new national rail one any time soon. But at least it won’t be Brent Cross Thameslink.

Jonn Elledge is the editor of CityMetric. He is on Twitter as @jonnelledge and also has a Facebook page now for some reason. 

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