4 ms·

How does this compare to damning water, in terms of evaporation?

ChuckMcM 3y ago
In terms of cost it seems way way cheaper. The water is stored near where it is needed (so no canals to dig), and you can throw up another one for $125K vs the millions of $ to build a dam. So I'm guessing the evaporation challenge isn't a deciding factor here. That said, I wonder how much longer you could keep the ice if you had reflective blankets to cover them once you've "grown" them as much as you can (enter the dry season).
- ChatGTP 3y ago
  Since white is reflective, why do you need blankets ?
  - quickthrower2 3y ago
    I imagine a shiny reflective blanket will reflect more infrared than just snow, and also trap coldness in the air between it and the snow, acting as insulation.
  - wombatpm 3y ago
    Dirt and dust settle on top, those particles trap heat and facilitate melting
    - flybrand 3y ago
      Doesn’t it settle on the tarps / covering too?
      - maxbond 3y ago
        It's a lot easier to remove dust from a dry surface (the wind may do it for you - I recently listened to an interview about Mars rovers[1], and they mentioned most of the dust that gets on their cameras gradually blows away). [1] https://embedded.fm/episodes/371 https://embedded.fm/episodes/371
    - maxbond 3y ago
      I'm having trouble remembering the name (it's obtuse and my searching is bringing up different, similar phenomena - cryo-something iirc), but once the warm dust starts to dig a little hole with some fresh water in it, biofilms of algae and fungi begin to form at the bottom. They're dark colored and accelerate the process further (increasing the size of their habitat). At least, that happens with real glaciers. It may take a while for a similar phenomenon to arise on artificial glaciers. But sure as sunshine, if there's sunlight and fresh water, the algae will figure out a way to exploit it.
      - Gh0stRAT 3y ago
        Is the term you're looking for "cupping", ie the formation of "sun cups"?
        maxbond 3y ago
        Interesting, I hadn't heard that before, but it's certainly related. The word I was searching for was the term for this particular biofilm/community, so it's some long technical term.
      - williamdclt 3y ago
        I always wonder that about seemingly-spontaneaous fungus and algea appearance: where do these organisms come from? Are they somehow airborn, or rainborn?
        marcosdumay 3y ago
        Yes to both. There are plenty of organisms on any drop of water you can find on nature, and plenty of spores on the air.
      - mjhay 3y ago
        Those are called "cryoconites." If the debris over a glacier exceeds a millimeter or two, it will actually reduce melt instead.
        3y ago
  - j-a-a-p 3y ago
    Color only hints to heat reflective properties. Most of the heat of the sun is not carried in by the visible spectrum. And concerning snow, it is not particularly good at reflecting IR (1). More a conceptual objection to using blankets. Feels like overengineering. The Ice Stupa idea of Sonam Wangchuk is brilliant IMO and if this minimalist approach would work would be fantastic. (1) https://apps.dtic.mil/sti/pdfs/ADP000147.pdf https://apps.dtic.mil/sti/pdfs/ADP000147.pdf
- antupis 3y ago
  Long if you have high-tech blankets https://www.snow-forecast.com/whiteroom/finnish-resort-to-create-glacier-for-skiers/ https://www.snow-forecast.com/whiteroom/finnish-resort-to-cr... but you can also low a tech version with saw dust https://www.swissinfo.ch/eng/sawdust-slows-rate-of-melting-snow/39224 https://www.swissinfo.ch/eng/sawdust-slows-rate-of-melting-s... which is also good.

In terms of cost it seems way way cheaper. The water is stored near where it is needed (so no canals to dig), and you can throw up another one for $125K vs the millions of $ to build a dam. So I'm guessing the evaporation challenge isn't a deciding factor here. That said, I wonder how much longer you could keep the ice if you had reflective blankets to cover them once you've "grown" them as much as you can (enter the dry season).

ChatGTP 3y ago
Since white is reflective, why do you need blankets ?
- quickthrower2 3y ago
  I imagine a shiny reflective blanket will reflect more infrared than just snow, and also trap coldness in the air between it and the snow, acting as insulation.
- wombatpm 3y ago
  Dirt and dust settle on top, those particles trap heat and facilitate melting
  - flybrand 3y ago
    Doesn’t it settle on the tarps / covering too?
    - maxbond 3y ago
      It's a lot easier to remove dust from a dry surface (the wind may do it for you - I recently listened to an interview about Mars rovers[1], and they mentioned most of the dust that gets on their cameras gradually blows away). [1] https://embedded.fm/episodes/371 https://embedded.fm/episodes/371
  - maxbond 3y ago
    I'm having trouble remembering the name (it's obtuse and my searching is bringing up different, similar phenomena - cryo-something iirc), but once the warm dust starts to dig a little hole with some fresh water in it, biofilms of algae and fungi begin to form at the bottom. They're dark colored and accelerate the process further (increasing the size of their habitat). At least, that happens with real glaciers. It may take a while for a similar phenomenon to arise on artificial glaciers. But sure as sunshine, if there's sunlight and fresh water, the algae will figure out a way to exploit it.
    - Gh0stRAT 3y ago
      Is the term you're looking for "cupping", ie the formation of "sun cups"?
      - maxbond 3y ago
        Interesting, I hadn't heard that before, but it's certainly related. The word I was searching for was the term for this particular biofilm/community, so it's some long technical term.
    - williamdclt 3y ago
      I always wonder that about seemingly-spontaneaous fungus and algea appearance: where do these organisms come from? Are they somehow airborn, or rainborn?
      - marcosdumay 3y ago
        Yes to both. There are plenty of organisms on any drop of water you can find on nature, and plenty of spores on the air.
    - mjhay 3y ago
      Those are called "cryoconites." If the debris over a glacier exceeds a millimeter or two, it will actually reduce melt instead.
      - 3y ago
- j-a-a-p 3y ago
  Color only hints to heat reflective properties. Most of the heat of the sun is not carried in by the visible spectrum. And concerning snow, it is not particularly good at reflecting IR (1). More a conceptual objection to using blankets. Feels like overengineering. The Ice Stupa idea of Sonam Wangchuk is brilliant IMO and if this minimalist approach would work would be fantastic. (1) https://apps.dtic.mil/sti/pdfs/ADP000147.pdf https://apps.dtic.mil/sti/pdfs/ADP000147.pdf
antupis 3y ago
Long if you have high-tech blankets https://www.snow-forecast.com/whiteroom/finnish-resort-to-create-glacier-for-skiers/ https://www.snow-forecast.com/whiteroom/finnish-resort-to-cr... but you can also low a tech version with saw dust https://www.swissinfo.ch/eng/sawdust-slows-rate-of-melting-snow/39224 https://www.swissinfo.ch/eng/sawdust-slows-rate-of-melting-s... which is also good.