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by defrost 1032 days ago
> In the desert, the earth itself is hot and if go underground, it will only get hotter.

Not the case in practice ...

    It can get to be 42ºC (108 Fahrenheit) in the Australian town of Coober Pedy — and that's in the shade. With opal mines that look like giant ant hills and a network of underground dwellings where residents live, this is the kind of place where the searing heat warps perspectives, and yet somehow clarifies them. [1] (corrected, npr got the common summer max temp conversion wrong)

    The miners quickly discovered the advantages of living underground to escape the heat of the summer and winter's cool desert nights. No matter how harsh the climate, the underground rooms maintain a comfortable, even temperature ranging from 23ºC to 25ºC day and night throughout the year. [2]
[1] https://www.npr.org/2007/08/17/12873915/coober-pedy-one-of-e...

[2] https://www.cooberpedy.com/underground-living-dugouts/
1 comments
rawgabbit 1032 days ago
It could be that “Most dugout homes are excavated into hillsides rather than dug from shafts” from your second article. AFAIK temperature doesn’t get cooler underground. https://en.wikipedia.org/wiki/Geothermal_gradient
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defrost 1032 days ago
Hi, I'm in actual geophysics .. and you're linking to a phenomenon (quick, read your own link) that occurs over a scale of tens, hundreds, and thousands of kilometers.

Near surface underground is different.

Aquifers and all manner of other things behave differently to your blanket "AFAIK temperature doesn’t get cooler underground" and it's well known in practice that digging down a few stories evens out the tempreture compared to above ground.

This even works as a cheap passive cooling system for data centers:

https://pawsey.org.au/groundwater-cooling-system/

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h2odragon 1032 days ago
data center was the original reason for my buried wall: the computers were going to live on that wall and shed their heat into it. Big heatsink. Worked well for a couple years and then AT&T decided to take away my bandwidth, so i had no more excuse to have 10kw of racks running.
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