Tuesday, November 9, 2010

It's Cold Outside (Il Suo Freddo)

Global warming and rising ocean levels were a problem the ancient Romans might have dealt with to a degree. They were a few shades closer to the last ice age and didn't build as frequently as the 'strip malls' which go up here in the modern US every day. I worry about water levels in Venice destroying great architecture and history whenever I go to Italy.

Modern handwringing about the loss of ice caps and glaciers prompted me to think about the situation.

















People say 'global warming' but really the only observable phenomenon I see are less ice and some upper atmospheric changes. Since my 'junk science' thinking can't come up with anything at the moment for the upper atmosphere, indulge me my ramblings about ice today...

When fresh water is floating around in salt water, what is the actual mechanism for melting scientifically speaking? Well if you are like most people and said a rise in temperature, then you are partially correct, on the surface. But consider that the ice is floating in near freezing cold salt water, which is actually colder than freshwater ice (back in ancient times, they say the Romans made ice cream with salt water to make things even colder).

And, there is no shortage of volume of that colder-than-ice salt water compared to the thin ice crust. Even large glaciers are not nearly as tall as the depths of the Arctic Ocean, right?

So I understand the melting of freshwater ice in salt water to be related to the edges (of the ice that is). The salt particles contaminate the freshwater ice and lower its freezing point, which if the temperature is just under freshwater freezing, the freshwater ice melts away. The ice on the caps is replenished with weather systems (dropping fresh water rain, aka 'snow'), but maybe that's not enough? What if there are other particles (air delivered chemicals or residue) which lower the freezing point of the polar ice like salt does?

My half-baked solution to all this would be create enormous desalinization / filtration plants at the poles to remove contaminants; a kind of 'Santa's Workshop' of fresh water. The fresh water would then be pumped onto remaining polar ice where it could refreeze because it is still colder than freezing in those places.












To do this on such a large scale to affect ocean levels would require enormous power, and nuclear fission springs to mind. Of course, that generates large amounts of heat which could be counter productive unless it was used really really efficiently. Does anyone have a cheap limitless power source that operates at low temperatures to be used in this project? Will you give that to me for free?

12 comments:

  1. I forgot to mention this would only work on the South Pole / Antarctican continent. Anyone venture a guess as to why?

    ReplyDelete
  2. You lost me at Venice. I started thinking about James Bond movies. Reading this has made me realize how much smarter you are than me. Global warming/climate change is a topic I am scared to share my opinion on, but I will say I think we give ourselves more credit or blame than we deserve when it comes to being able to change the environment.... That is, until you construct your South Pole machine. By the way, I think a James Bond Villain may already have a secret lair down there you could operate out of.

    ReplyDelete
  3. I actually heard that they have thought of a way to reverse global warming...sure wish I could remember what it was.

    Something about pulling a hose miles long into the air and releasing a chemical that would bring us back to 1940's atmosphere or temps...
    The only downfall that they could think of was more acid rain. Lovely.

    I'm going to go look for that interview so I can sound a little more intelligent.

    ReplyDelete
  4. We say 'climate change' to stop everyone thinking it is all just about everywhere just getting warmer.

    What about huge wind turbines? I am being silly....
    I am pretty sure the problem you cite is the problem...the amount of energy expended in moving all that water would be huge...and its production damaging in itself. You'd also be adding on top ...so as the mountain became higher you'd need to expend more energy getting it 'up'. Also with the 'laws' of energy conservation, overall the average temperature is going up....the idea that a little pocket on the south pole would retain its coldness to keep freezing might not be the case.....

    I will ponder on this more I am sure...with a proper physics head on

    ReplyDelete
  5. No - I have not thought it through properly at all.....and I have to go eat now

    ReplyDelete
  6. I have thought it all through and the answer lies in...penguins. They'll sort it for you using just a little fish power.

    Sorted.

    ReplyDelete
  7. You make ice cream today by using water with high salinity to the cream down past its freezing point.

    Okay, so the oceans have salts in them, which, as you pointed out, suppresses the freezing point (the same reason why we spread salt on the roads in the winter). However, now you have a system which (we'll assume it's closed, for simplicity's sake) is colder than the iceberg.

    The iceberg's temperature is 0 degrees celsius. Again, for simplicity's sake, we'll just say that the molality of the ocean is enough to give a 1 degree point of depression, so now the water temperature of the ocean is -1 degree.

    In this scenario, the iceberg should not thaw, because the ocean temperature is colder than the freezing point of the pure water.

    This should render the point moot.

    However, as the fresh water melts, the molality of the oceans is actually decreasing, which means the freezing point is no longer being suppressed as much, as the salt dissolved in the solution is no longer as great.

    So now we have a system in which the salinity of the salt water is slowly (but, theoretically, surely) approaching the salinity of the fresh water, which means there would be no colligative effect of the salt water.

    Bear in mind, also, that water at different temperatures (and pressures) will dissolve different amounts of a solute (we'll say salt, to keep it "simple") which means that, even across 10 feet of water at the poles, you'll have a gradient of temperature suppression thanks to the solute, so you would have to figure out a way to get the water to hold equal amounts of salt across various depths in order to help cool the oceans enough.

    But if we cool the oceans, then the icebergs will grow faster since the salt water is no colder than the freezing point of the water, which then would cause more ice to grow. As the ice grows, the solute falls out of solution, increasing the molality of the oceans and further depressing the freezing point, making the oceans even colder.

    BUT THEN, remember that, as water freezes into ice, it is giving off energy, which will then raise the temperatures of the ocean. As the temperatures of the ocean rise, it will cause more ice to melt, which absorbs heat energy, which will then cause the temperatures to dip, which will cause the molality of the oceans to rise, which will cause more ice to form!

    ReplyDelete
  8. this is why it's simpler to say "Mankind is causing the climate change" and call it a day.

    Really, it's most likely the isthmus of Panama's fault, anyway.

    And to answer Molly Potter's comment, someone suggested spraying sulfuric acid in the upper atmosphere. It would reflect enough of the sun's rays to cause the global temperatures to dip, thus saving us from ourselves. *eyeroll*

    It's the same thing that plunged the Earth into an effective nuclear winter after the asteroid hit the Earth, wiping out the dinosaurs. It was something like four years for enough of the sulfuric acid to fall out of the atmosphere for the Earth to right itself.

    ReplyDelete
  9. Molly's on to something I reckon. Penguin guano for your power station. At last, a viable use for those unlovable little brutes!

    I'm all for just painting the poles white, and hoping the resulting change in albedo will do the trick.

    And thanks for bringing my strange last post to my attention. I have no idea why Yahoo tried to out me!

    ReplyDelete
  10. I had a hard time to pass Science exams.
    Re your comment on my last post, I am truly flattered! I do not know how to start but I have a fairly clear picture of the main theme, know nothing about publishing, it may be an ebooklet. I do not know. It may be a dream in the cassetto. Yeah that is probably it.

    ReplyDelete
  11. Tom,
    That was a great James Bond film! I'm not all that smart, just plagued with random thoughts sometimes. You are absolutely right, I do need a lair.

    Nikki,
    No to acid rain! It will melt any marble I have outside!

    Molly,
    Penguins, of course. And, sorted. :)

    MJenks,
    So, the freshwater melting can serve as kind of a 'buffer' to the other salt water? But wouldn't the wave action move it away, bringing in saltier water next to the fresh ice? And, if the fresh water was pumped up on a land mass to refreeze, then it wouldn't be displacing ocean water, thus the water levels go down around the world (of course, that would be a pretty fng tall ice berg to have an actual effect)?
    Good point about the energy created when the water is freezing. And of course I covered all situations by playing the 'it would work if I had infinite energy at no costs' card.

    The Jules,
    Penguins are the smelliest birds on earth, I think. I saw some once at SeaWorld in San Antonio, Texas. Their guano is probably four times as powerful as any other birds'.

    Mosaicista Appassionata,
    :)
    But you approach things very logically, how is there trouble with science?

    I think you will make a great book and I was serious. We have many common interests with mosaics, and I'm glad that I know you.

    ReplyDelete