Complex Numbers

Down Under

Something interesting from the BBC last year:

    The Australian town where people live underground  

I thought all Australians lived underground. Otherwise, they'd fall up into space.

I mostly saved this article so I could use the entry title I did. I'm inordinately proud of that pun. But it's also a fascinating concept, at least to me.

These are the first signs of Coober Pedy, an opal mining town with a population of around 2,500 people. Many of its little peaks are the waste soil from decades of mining, but they are also evidence of another local specialty – underground living.

That name sounds as Australian as kangaroos and Crocodile Dundee. I wonder if the article will state its origin.

In the winter, this troglodyte lifestyle may seem merely eccentric. But on a summer's day, Coober Pedy – loosely translated from an indigenous Australian term that means "white man in a hole"...

Of course it did, and it's hilarious.

...needs no explanation: it regularly hits 52C (126F), so hot that birds have been known to fall from the sky and electronics must be stored in fridges.

Yeah, I prefer heat to cold, but that's just going too far. I thought Phoenix was bad in the summer.

As the blistering three-month heatwave continues in the US – with temperatures even cacti can't handle – and wildfires incinerate swathes of southern Europe, what could we learn from Coober Pedy's residents?

Again, this article is from last year. August, specifically. At least it was winter then in Australia.

People have been retreating underground to cope with challenging climates for thousands of years, from the human ancestors who dropped their tools in a South African cave two million years ago, to the Neanderthals who created inexplicable piles of stalagmites in a French grotto during an ice age 176,000 years ago.

Well, duh. It's not exactly news that humans and related apes lived in caves.

Caves served another very important purpose, as well. As the article notes, most underground locations that are deep enough—provided one isn't near a volcano or whatever—stay around 13C, or 55F. Before refrigeration, this was an common way to keep beer and wine relatively chilly, and thus preserve it longer. Even now, a lot of fermented beverages are best served at "cellar temperature."

Apart from comfort, one major advantage of underground living is money.

That, and your HOA can't give you shit if you happen to paint your house the wrong shade of pink.

On the other hand, many underground homes in Coober Pedy are relatively affordable. During a recent auction, the average three-bedroom house sold for around AU$40,000 (£21,000 or US$26,000).

I'd imagine that at least part of that is its remote location.

The question is, could underground homes help people to cope with the effects of climate change elsewhere? And why aren't they more common?

Guessing that at least part of the answer to that last question is "rock" and "water tables." And also "building codes" and "zoning laws." It's my understanding that, to be considered a bedroom in the US, a room must have a window. Windows aren't exactly a common feature of underground living.

Besides, if your neighbor lives in a cave, how are you supposed to judge their lifestyle by how they keep their yard?

There are several reasons why making dugouts in Coober Pedy is uniquely practical. The first is the rock – "It's very soft, you can scratch it with a pocket knife or your fingernail," says Barry Lewis, who works at the tourist information centre.

Okay, so I might have cheated a bit with my "rock" answer, because further up in the article, they mentioned it was sandstone and whatnot.

However, the feats at Cooper Pedy would not be possible everywhere. One major challenge with any underground structure is damp.

I did say "water tables." Civil engineering education is good for something.

But in Coober Pedy, which sits on 50m (164ft) of porous sandstone, conditions are arid even underground. "It's very, very dry here," says Wright. Ventilation shafts are added to ensure an adequate supply of oxygen and to allow moisture from indoor activities to escape, though these are often just simple pipes sticking up through the ceiling.

The downside of building, even underground, in a desert is the other side of that equation: where do you get your water? I missed it if the article addresses this. I imagine there's an aquifer further down, but I don't know.

The article also doesn't note another important thing about learning how to live underground. If we end up with people living on the Moon and/or Mars, they're pretty much going to have to do so in underground habitats. Not only does the rock above you provide a barrier to space radiation, but it all but eliminates potential problems with small meteorites punching a hole in your bio-dome or whatever.

Also, nearly unlimited beer storage.