29 ms·

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.
    - maxbond 3y ago
      Thank you! That's so interesting that it can actually slow the melting.
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

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.
  - maxbond 3y ago
    Thank you! That's so interesting that it can actually slow the melting.

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