With heat records falling all over the world, July 2023 was the warmest month in history, and not by a little. Residents of Phoenix endured over a month of highs in excess of 110 degrees, and that’s just one small example. We have just seen the scenes of incredible devastation in Lahaina, Hawaii, where a wildfire, fueled by hurricane-force winds and tinder-dry invasive grasses, burned the entire city to the ground. With all these warnings of deadly heat I’m surprised no-one has suggested that it may be our destiny, as the planet continues to heat up, to start living underground. That’s why I was fascinated to read a BBC articleabout a town in Australia—a place where summertime highs regularly hit 125 degrees—where people have been living underground for a long time. The town is Coober Peedy, a mining town of 2,500 about 500 miles north of Adelaide. Its name, loosely translated from the indigenous Australian, means “white man in a hole,” and although some of the town is above ground, many of its residents have carved underground houses—some quite luxurious–from sandstone. It’s quite dry underground, so in winter residents don’t have to worry about mold or seepage, and the temperature underground is a comfortable 70 degrees year round.
Historically, there have been other instances of underground living, according to the BBC articles. In the 2nd century AD Jews looking to evade Romans built the so-called Hazan caves. The sandstone carved temple in Petra is world famous (also made from sandstone), as are the Pueblo cliff dwellings in Mesa Verde, Colorado. But these are isolated examples, the question now is, is dwelling underground a solution to a worst-case climate warming crisis? I did some quick research and it doesn’t appear that the subject has been well-studied. There is a firm named Oppidum that is offering luxury underground dwellings in the United Arab Emirates—an area that will be among the first to suffer from unlivable heat if current trends continue. But Oppidum’s structures are for the ultra-wealthy, and emphasize security as one of its main features. Their model is not replicable for people of ordinary income.
Then there is the NEOM model city under development in Saudi Arabia. This is an enormous undertaking, envisioned as a 10,000 square mile city-state, funded with an investment of 500 billion, and is being touted as the energy sustainable, luxury urban solution for the future. But it is being built in the open desert, and partly, it seems, on the ocean as well. It doesn’t appear to take into consideration that in that part of the world temperatures may soon rise above the level compatible with human life. In a worst case scenario, where the rise in temperature becomes so catastrophic that planet earth starts to resemble Venus, with surface temperatures of 900 degrees, underground living would not be optional, but critical for survival. There are all sorts of geo-engineering solutions being proposed and tested, including some that attempt to capture carbon into a solid mineral and sink it into the bottom of the ocean, but these efforts are many orders of magnitude too small to make a difference.
Is Coober Peedy a possibility for human survival in a scenario where the alternative is something close to extinction? Digging in sandstone is easy, and it is a rock that is stable without additional bracing or support, even in an earthquake. But elsewhere underground living would require a massive effort of construction that would dwarf anything ever attempted—something like the Tokyo subway’s underground cities times ten million. Elon Musk wants to colonize Mars, but I wonder if he and the other visionary billionaires working on a possible future for humankind have thought about staying here on Earth for the few thousand years it would take for the planet to cool down.
Jules Verne and H.G. Wells, where are you? Actually, in H.G. Wells futuristic novel Time Machine, some portion of humanity does live underground. I, like most of humanity, enjoy living and breathing on the “green hills of earth”—to borrow from the title of another famous science fiction novel—but what happens if we have no choice? I won’t live to see what happens, but I can still dream and think about it, which is what we all need to do now.