I was researching Hong Kong as a destination of work, for a friend who was thinking of taking up a job there, and came to the realization that good information on what it is like to live in a city, is hard to find.  Anyway, through the course of my excavations, I chanced upon a rather interesting website – Batgung – maintained by two expats who’ve been living in Hong Kong for over a decade… And, through them, learned that Hong Kong makes an intriguing contribution to Saving the Earth !

Well, we get told over and over that using up too much land for development is one of the primary environmental sins. You constantly hear about the terrible ‘footprints’ we humans leave on the earth’s surface. Clearing land to build on lies behind deforestation, species extinction, and so on.

I started thinking about this the other day as I was jogging around my ultra-high-rise neighborhood in Hong Kong. What kind of ‘footprint’ was I leaving on the earth’s surface, i.e. how much space was I taking up?

3 people x 8 flats x 50 stories x 15 towers = 18,000 people in my housing estate

Next, I reckoned my estate occupies a plot of land that’s around 400 meters long, and averages just under 100 meters wide – let’s say 90… the Tall Estate’s area: 36,000 square meters…. 36,000 square meters divided by 18,000 residents means each member of Mr Tall’s housing estate occupies just about exactly two square meters of the earth’s surface.

What’s even more interesting is when the authors put the figure of “two square meters”, in perspective :

That is, to house the world in Mr Tall style, we need a housing estate that covers 14,000 square kilometers… To put this into some perspective, Ireland comprises 70,000 square km, so our estate would take up just one-fifth of that one small island… And, oh yeah, the rest of the whole world would be free for a farm or two, and maybe for some parks and wildlife preserves.

How much space would it take to house the world at the Hong Kong standard, i.e. at an actual density of 31,000/square km (assuming its stated population density of 6,200/square km is based on the entire land area of the SAR of which at most 20% is actually built-up), in an urban area that took up 20% of a broader area that could remain unspoiled?

Using our figure of 7 billion people, I come up with an overall area of roughly 1.1 million square kilometers. That comes out to just .74% — i.e. not even one percent — of the world’s total land area (which is 148,000,000 km2).

Think about that for a minute: 99.85% of the world’s land without buildings of any sort.

Imagine…