China’s Pearl River Delta overtakes Tokyo as world’s largest megacity | Hacker News Reader

China’s Pearl River Delta overtakes Tokyo as world’s largest megacity

theguardian.com

80 pointsprotomyth44 comments

They managed to write an article comparing the populations of the Pearl River Delta and Tokyo without actually giving the population of either. Nice work.

They've also picked a photo of downtown Guangzhou on a smoggy day (because all Chinese cities are polluted, don't you know...)

In actual fact it gets about 10 times fewer smoggy days than Beijing. Still bad, but I have found the weather to really be quite nice.

The local equivalent of Google Maps is done in an isometric SimCity-style cartoon format which looks really cool.

http://gz.o.cn/

Scroll down and to the left a bit to see the area depicted in the photo - it's a new(ish), central park positioned over a shopping mall.

Yeah, was annoying to have to google the stats. For reference the pear river delta has 63 million people.

If we're going to compare apples to apples, the Yangtze River Delta (including Shanghai, Hangzhou, Nanjing, and other cities, all of which are very close to each other), is substantially bigger.

http://en.wikipedia.org/wiki/Yangtze_River_Delta

Yeah, the article really needs to specify what its definition of "megacity" is. The YRD is a patchwork of many different cities, towns, and villages, some parts of which are substantially less urban that others. If you take the train from Shanghai to Hangzhou, you'll pass by some farmland on the way. I'm sure the Pearl River Delta is no different.

The distances between any 2 of Shanghai, Nanjing, and Hangzhou on a map looks far greater than Beijing to Tianjin, or Guangzhou to Shenzhen, so perhaps Beijing-Tianjin and Pearl River Delta would qualify as urban conurbations in way that the Yangtze River Delta doesn't.

A fair amount of people commute daily from Tianjin to Beijing, so I think it is a fair comparison.

The commute (train) takes about 1 hour (per direction, so 2 hours per day), and is good for people with offices/homes near the terminating station, but not so good for people that need an additional 1-2 subway rides to their office.

One hour commute times are pretty typical for largish modern Chinese cities.

Shanghai and Nanjing are rather far away from each other. It's more common to talk about how Shanghai, Suzhou, and Wuxi are growing together to form a massive conurbation. The YRD is more of a broad economic zone and not really comparable to Tokyo or really the Pearl River Delta.

The article doesn't actually mention the population of the Pearl River Delta, which I find a bit odd... anyway, from Wikipedia:

Population • Metro 63,724,157~120,000,000

http://en.wikipedia.org/wiki/Pearl_River_Delta

For comparison Tokyo's metro population is 35,682,460. http://en.wikipedia.org/wiki/Tokyo

That did seem like a strange omission, agreed. Neither is quite what we would traditionally have called a 'city', though - Tokyo is an entire prefecture (aka state, or province, depending on how your country divides its regions), the PRD is a Gibsonesque Sprawl of huge cities and smaller ones. So while I agree with the general premise that these are the largest urbanized areas in human history, we will need to revise our terminology to call them cities (or they'll need to implement a single local government, tax structure, address and street naming, etc. to fit the exiting definition).

It sounds like you refer to the definition as it is in the USA, which is not exactly the same as it is in the rest of the English speaking world.

Perhaps the world needs a new term for these sorts of conglomerations.

Wikipedia's Guangdong page reports the total provincial population as 106 million so perhaps 63 million is the correct number. When the newspapers in China about 3 years ago first reported plans to merge the city administrations and infrastructure of Guangzhou, Dongguan,Shenzhen, and some nearby smaller cities, they estimated the population as 43 million. The extra 20 million must be from the non-urban areas in the region pictured on Wikipedia's Pearl River Delta page.

The total area of the Pearl River Delta is about 40,000 km^2... The total area of the Greater Tokyo Area is about 4,000 km^2... Seems like a pretty arbitrary comparison if you ask me.

>The total area of the Pearl River Delta is about 40,000 km^2.

The definition of the urban land for PRD and Tokyo as used by the World Bank report is ~7000 square kilometers (PRD) and ~5500 square kilometers (Tokyo).

They do not count the entirety of either of the two. For the aforementioned areas (that they deemed urban land), they estimated them to have populations of around 42M (PRD) and around 31M (Tokyo).

This area excludes Hong Kong and many other parts.

Grauniad did a very poor job at getting the World Bank report's message across.

Of course larger metros will be...well...larger. I don't think the physical area is meaningful. How about integrated infrastructure, commerce, social groups, etc?

Of course it's meaningful. Because, due to its size, the Pearl River Delta contains what are essentially 11 different cities - each with its own city center. Where as the Greater Tokyo Area includes 6 - all substantially smaller than, and largely centered around, Tokyo.

Speaking about your other attributes... I think the most telling thing about the Pearl River Delta is that 2 of those 11 cities were governed by the UK until 1997 - and you still have to pass through customs and immigration to cross into and out of them...

"each with its own city center" vs "largely centered around Tokyo" is the answer then - Tokyo is cohesive, PRD is not.

The customs thing is interesting. Citation?

Exactly, but that's why the area IS meaningful... Something the size of the Pearl River Delta can't possibly be cohesive enough to qualify as a single metropolitan area (yet). So comparing it to one is a bit arbitrary.

Also, those two cities I was talking about are Hong Kong and Macau. Both were governed by the UK from the end of the First Opium War (1842) until 1997, when control was handed back to China. The terms of the handover included maintaining independent boarders (and forbidding complete freedom of movement and immigration). You can read about it and the other terms of the handover here (http://en.wikipedia.org/wiki/Transfer_of_sovereignty_over_Ho...).

Macau was governed by Portugal and was handed back in 1999. It had been rented by the Portuguese since 1557.

Oh, duh. Yeah. But, still separate customs and immigration.

I don't know about 'citation', but when I crossed from Hong Kong to Shenzhen last month I had to exit Hong Kong's immigration and enter China's and vice-versa on the way back.

It's substantially easier to visit Hong Kong than China (visa at the airport vs. visa in your home country before you travel), unless you have an APEC card of course

You can also buy (180 rmb for most countries) a 5 day visa for Shenzhen at the Luohu border too but the visa is not valid for Guangzhou or Dongguan.

The article sort of misses the real issue- the demographic. The PRD is very young, well educated and highly ambitious. Tokyo has the education, but it otherwise increasingly stagnant.

New difficulties here in Shenzhen buying the required markers of Chinese status (cars and houses) mean young Chinese are increasingly interested in startups and entrepreneurship as an alternative signaling method.

Why is this getting downvoted? Tokyo's population is projected to peak in 2020 and then go into rapid decline (joining the rest of country, which is already shrinking fast). The PRD is set to keep growing for at least several decades, although eventually China will hit the same crunch.

The region is not as tightly integrated as Tokyo though. There's a good chunk of people who commute daily from Shenzhen to Hong Kong through the electronic customs but for most people, going in and out of the mainland is not that simple. The culture on both sides of the border is also very different. It's only anecdote but a surprisingly high percentage of my friends in Hong Kong have never set foot in Shenzhen (let alone Guangzhou) and vice versa (I live in Shenzhen). I've even had friends tell me they were scared of going to Shenzhen because they don't consider it "civilised" (which is laughable of course).

This is a pretty debatable claim, since it depends almost entirely on how you define what "a" "city" is. By UN stats, the PRD is now the world's largest "urban area", but Tokyo still retains the top spot as world's largest "metropolitan area", and by a long shot (37m vs #2 Seoul at 25m).

https://en.wikipedia.org/wiki/World%27s_largest_cities

I was in Hong Kong last week and one of the things that amazed me is that the "city centre" (Kowloon and Hong Kong Island) is fairly small and has lots of green spaces. Hong Kong Island has a density of 16,000/km2 but the actual urban area is around 20% of the island [0]. Housing really is densely packed (I haven't ever seen people queuing for an elevator to get into their apartment building before), but I think I'd much prefer that to living in an urban sprawl where I have to drive 30 minutes to see something green.

[0] https://www.google.com/maps/place/Hong+Kong+Island,+Hong+Kon...

I am from Hong Kong and I had relatives in Foshan, and, on a good day, it was a 4 hour "commute" to visit them, through two sets of customs and 2 to 3 changes of transportation so I'm not sure how they can be counted to be in the same city.

I don't think they are including Hong Kong - at least it's not labelled on the map.

Ok. I saw Hong Kong listed in http://en.wikipedia.org/wiki/Pearl_River_Delta

And the inevitable march towards the future we learned about in 90s cyberpunk gets a little closer. Needing to cross through customs to get between different parts of what's essentially a contiguous urban area makes this just a little more salient.

I wonder of the US northeast counts as a single megacity.

It is a megalopolis! http://en.wikipedia.org/wiki/Northeast_megalopolis

"A megalopolis (sometimes improperly called a megapolis) or megaregion is typically defined as a chain of roughly adjacent metropolitan areas. The term was used by Patrick Geddes in his 1915 book Cities in Evolution,[1] by Oswald Spengler in his 1918 book, The Decline of the West, and Lewis Mumford in his 1938 book, The Culture of Cities, which described it as the first stage in urban overdevelopment and social decline."

vs megacity: http://en.wikipedia.org/wiki/Megacity

"A megacity is usually defined as a metropolitan area with a total population in excess of ten million people.[1] A megacity can be a single metropolitan area or two or more metropolitan areas that converge. The terms conurbation, metropolis and metroplex are also applied to the latter."

NYC alone is a megacity. The US northeast is a megalopolis.

An easy way to tell, I think: a megacity very likely has a single encompassing public transit authority, because the transit needs of the individual underlying municipalities involve a lot of "I live in this city, work in that city, and need to commute every day" and that can't be easily handled if it's a bunch of separate systems.

The Vancouver Metropolitan Area in British Columbia, for example, is six cities, with one transit system. There's also the Greater Vancouver Regional District, which is a megalopolis that consumes a few more adjacent cities, but those aren't linked by transit.

This doesn't always work, the Greater Toronto Area (GTA), even if you take the most narrow interpretation, is made up of a bunch of different transit systems. Walking along on Google Streetview, there is no way you could tell when on Yonge Street you have "left Toronto", and need to pay extra fare on TTC, or take YRT/Viva/Blue etc.

But it's a neat idea to think about transit and accessibility. I'd love to know at which point in the world you can reach the most people within an hour of transit for example, or two hours... This is the advantage in the Pearl River Delta (and probably Tokyo) - there is tons of high-speed rail, subways etc, so you can probably reach about 40 million within 1.5 hr (an hour high speed rail and half an hour on local transit). Whereas it takes me an hour and a half just getting to the airport in Toronto.

I like this. The next step down must surely be the Super City. In New Zealand the Auckland "Super City" would love to be a mega city. Auckland's fragmented and disconnected transport system, chaotic local government arrangements and expensive attempts at integration make it substantially less than a megacity. That and the low population count.

Oh I like that definition. Means that you'd count the Gold Coast and Brisbane (and Ipswich) together as a megacity, which is kinda true, as "South East QLD".

The GVRD renamed itself to the Metro-Vancouver about 5 or 6 years ago. The Vancouver Metro area is the exact same thing as the GVRD. They aren't different things.

I don't like this, because it means the Bay Area will likely never be considered a megacity :(

LA County and SoCal too perhaps?

In high school geography they called it a megalopolis: http://en.wikipedia.org/wiki/Megalopolis_%28city_type%29

And the US Eastern Seaboard was the canonical example, from Northern Virginia/DC up through Boston is about 50M people.

Ask Chinese people if they would live in Tokyo.

not sure what the point is, but there are Chinese people living in Tokyo. There are about 300 000 Chinese people in Japan, I happen to know a few of them personally.

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