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For those saying "they're all over the world", it's not clear from the article but there's literally wind flowing from inside the mountain and that's flowing al

For those saying "they're all over the world", it's not clear from the article but there's literally wind flowing from inside the mountain and that's flowing all year around at ~10°C, even during summer when it's 35C outside. I live in a valley nearby, but in Italy, we have them too. I'm not aware of similar places elsewhere, at least not at the scale we have them here (every little town has their own place where they found the cool air flowing out). Built centuries ago, they're still used to store wine by the old people in town. Sometimes I go there to cool down in summer. Very different from a cellar.

robinsoh 4y ago
> there's literally wind flowing from inside the mountain and that's flowing all year around at ~10°C, even during summer when it's 35C outside Could you clarify? What do you mean by wind flowing from inside the mountain?
- massenpunkt 4y ago
  From the article: "The reason grottos worked so well as natural fridges is due to their excellent ventilation. Since they usually occurred on rockfall or on an accumulation of scree, they have a porous foundation that guarantees internal air circulation and results in a year-round stable temperature..."
  - s1artibartfast 4y ago
    I think more information is required to explain how porous scree leads to wind blowing out of the grotto
    - FastMonkey 4y ago
      Maybe rocks in the scree cool down the air in the pores between them. Cool air is denser so it sinks and flows out at the bottom of the porous layer, and new warm air is pulled into the ground towards the top of the scree pile. People found the places that cool air was flowing out and built these grottos there. Not saying I knew anything about these before 10 minutes ago, but that seems plausible to me.
      - s1artibartfast 4y ago
        Hey, I think it is an interesting concept and open to to ideas. Thanks for your ideas, my engineering brain would just love a picture of the physics
        carapace 4y ago
        IANAGeologist, but my understanding is that when a steady wind blows from underground it's often due to a naturally occurring trompe: water flowing underground entrains air bubbles which collect in caverns and leak back to the atmosphere. Trompes can be quite large. https://en.wikipedia.org/wiki/Trompe https://en.wikipedia.org/wiki/Trompe
AlgorithmicTime 4y ago

robinsoh 4y ago

> there's literally wind flowing from inside the mountain and that's flowing all year around at ~10°C, even during summer when it's 35C outside Could you clarify? What do you mean by wind flowing from inside the mountain?

massenpunkt 4y ago
From the article: "The reason grottos worked so well as natural fridges is due to their excellent ventilation. Since they usually occurred on rockfall or on an accumulation of scree, they have a porous foundation that guarantees internal air circulation and results in a year-round stable temperature..."
- s1artibartfast 4y ago
  I think more information is required to explain how porous scree leads to wind blowing out of the grotto
  - FastMonkey 4y ago
    Maybe rocks in the scree cool down the air in the pores between them. Cool air is denser so it sinks and flows out at the bottom of the porous layer, and new warm air is pulled into the ground towards the top of the scree pile. People found the places that cool air was flowing out and built these grottos there. Not saying I knew anything about these before 10 minutes ago, but that seems plausible to me.
    - s1artibartfast 4y ago
      Hey, I think it is an interesting concept and open to to ideas. Thanks for your ideas, my engineering brain would just love a picture of the physics
      - carapace 4y ago
        IANAGeologist, but my understanding is that when a steady wind blows from underground it's often due to a naturally occurring trompe: water flowing underground entrains air bubbles which collect in caverns and leak back to the atmosphere. Trompes can be quite large. https://en.wikipedia.org/wiki/Trompe https://en.wikipedia.org/wiki/Trompe

AlgorithmicTime 4y ago