Bright lights, big cities


China has, to put it mildly, a hell of a lot of big cities. But some of what gets said about them isn't terribly accurate. Chongqing, for example, isn't the biggest urban center in the world. Despite often being referred to in English as a "province-level municipality," more than three-quarters of its population lived outside the city limits of the Chongqing Urban Area as of the last census in 2010.

China's confusing administrative hierarchy is partly to blame for classifying Chonqing as a zhíxiá shì (直辖市 ), or "municipality administered directly by the central government". In the context of mainland territorial divisions, the scope of a "municipality" or "city" (shì, ) goes far beyond the typical definition of the word as used in other countries, and can include both urban and rural land. In short, Chongqing isn't really a city in the conventional sense. Same goes for Shanghai.

So, for those of us seeking a better yardstick for urbanization, is there a better option than spending hours futzing around with badly formatted data tables from local government yearbooks, trying to somehow tabulate the reality on the ground? Mercifully, yes:

(click for full-size)

In 2012 the NASA Earth Observatory released a slick Google Earth overlay based on satellite imagery of the Earth at night that gives a pretty good idea of which cities are the biggest and most developed by dint of their brightness. I edited the above image of greater China to enhance the contrast between dark and well-lit regions, and should note that the correlation between a city's nigh-time luminosity and its size (whether in area or population) is by no means one-to-one.

Even so, the NASA pics do a great job of showing cities not as abstracted data, but as they really appear from orbit. Not that we can't abstract a bit on our own, mind:

(click for full size)

Above is an inverted, black-and-white version with provincial/national capitals labeled for clarity. There are dozens of fun things to point out from this proxy map of urban China - for instance, the disparities in both size and density between Chongqing and the nearby capital of Sichuan province, Chengdu - but I'll leave them for you to discover. 

Author: Hudson Lockett (@KangHexin)