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Post by striker16 on Dec 15, 2011 16:17:11 GMT 1
If putting down salt on ice-covered roads dissolves the ice why is it that icebergs do not similarly dissolve in the salt-rich oceans?
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Post by mak2 on Dec 15, 2011 17:34:41 GMT 1
Salty water has a lower freezing point but it remains frozen if it is cold enough, which it often is in polar regions. Icebergs do melt when they drift to warmer latitudes but it takes time because of the large amount of ice involved.
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Post by striker16 on Dec 15, 2011 17:37:24 GMT 1
Salty water has a lower freezing point but it remains frozen if it is cold enough, which it often is in polar regions. Icebergs do melt when they drift to warmer latitudes but it takes time because of the large amount of ice involved. Thank you.
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Post by principled on Dec 15, 2011 19:13:21 GMT 1
Striker Did you see Frozen planet programme that showed ice forming under a glacier and moving downwards like a stalactite until is touch the ocean floor, where it then spread across it freezing slow moving animals in its path? Truly amazing. Anyway, if I remember rightly that freezing was created by a simple seed crystal. I mention this as it is contained in the link below. antoine.frostburg.edu/chem/senese/101/solutions/faq/why-salt-melts-ice.shtmlBTW, in Canada they use potash and not salt as that is readily available. Another useless piece of info! P
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Post by marchesarosa on Dec 19, 2011 12:16:20 GMT 1
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Post by striker16 on Dec 19, 2011 12:26:23 GMT 1
Striker Did you see Frozen planet programme that showed ice forming under a glacier and moving downwards like a stalactite until is touch the ocean floor, where it then spread across it freezing slow moving animals in its path? Truly amazing. Anyway, if I remember rightly that freezing was created by a simple seed crystal. I mention this as it is contained in the link below. antoine.frostburg.edu/chem/senese/101/solutions/faq/why-salt-melts-ice.shtmlBTW, in Canada they use potash and not salt as that is readily available. Another useless piece of info! P No, unfortunately I missed that one principled but maybe I can see it on BBC iPlayer.
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Post by marchesarosa on Dec 19, 2011 13:20:49 GMT 1
Try and see it, Striker. It was utterly fabulous. I did, however, wonder whether the growth of the "brinicle" had been computer enhanced or even computer generated. What do you think, principled?
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Post by striker16 on Dec 19, 2011 13:56:50 GMT 1
Try and see it, Striker. It was utterly fabulous. I did, however, wonder whether the growth of the "brinicle" had been computer enhanced or even computer generated. What do you think, principled? Apparently, there is some question about some of the material the BBC use in terms of its authenticity, although it is all very well presented.
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Post by principled on Dec 19, 2011 23:01:51 GMT 1
Thanks for the link Marchesa, I'd forgotten the correct name of the Brinicle. It's difficult to know whether the time-lapse photography was enhanced, but with the conditions under which those photographers worked they deserved any technological help they could get. The spreading of the ice across the sea floor and the freezing of those animals that could not escape was nature at its most amazing and its most cruel.
I don't know about you, but I get annoyed with the "purists" who complained that some shots were taken in a zoo. Well, if those purists think that the programme could be enhanced by footage of a polar bear and her cubs in a real winter lair in the Arctic, then why don't they get some skis and a camera and do it? Fat chance, I suspect! P
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Post by marchesarosa on Dec 22, 2011 4:47:08 GMT 1
I don't mind any technical help to portray natural events, principled. The polar bear giving birth was OK but I think they should have explained it was taking place in captivity instead of allowing the viewers to think it was happening under the snow in an Arctic den. For one thing it gives the credulous an unrealistic sense of man's control of the natural world. Photographing Emperor penguins in Antarctica is one thing, photographing a huge, fierce, man-eating mammal in her natural Arctic lair is quite another.
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Post by principled on Dec 28, 2011 12:02:19 GMT 1
Marchesa Remember we were talking about Brinicles and whether the photographic footage was real? Well, I've just come across this BBC page, which explains how it was done. Many complain about the BBC licence fee, but I wonder if any commercial broadcaster would have the funds to do this type of educational TV? www.bbc.co.uk/nature/16250444Happy New Year. P
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Post by mak2 on Dec 28, 2011 14:06:38 GMT 1
My complaint about the licence fee is that it all goes to the BBC. This gives the corporation a monopoly of public service broadcasting and allows its controllers to impose their left-leaning feminist views on the nation. Other organisations could produce more high quality material if they were paid a share of the licence fee to do so. It is wrong that so much of our media are controlled by one corporation.
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Post by marchesarosa on Dec 31, 2011 12:08:04 GMT 1
Thanks, principled, for the link explaining how the brinicle filming was done. Truly, money well spent to portray this! I wonder how much this series of programmes about our icy poles has helped people grasp the enormity of the false hype about ice-packs melting and flooding the world. Greater knowledge means a more reasoned perspective, one hopes.
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