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Juud
29th Dec 2006, 11:27
Temps have been around -1C/30F here for a number of days. The small lake that we overlook has frozen over and yesterday the first skaters were out on it. The newspapers warn that the ice in the region is not safe anywhere yet & 4 people have drowned over the past 24 hours.

Today, temp has dropped to -6C/21F. It´s foggy and we can´t see the lake. But we hear it. A very strange and ´unearthly´ sound, reminiscent of wale-singing, comes up continually.

It grows louder and dimmer, it is like nothing I have ever heard before, quite melodious but in a phantom-church-organ way.
It´s been going on since around midnight; 12 hours now. No creaking or breaking sounds, no ice-plates rubbing against eachother grating sounds, just the very loud ´music´.

Anybody a clue what might be causing this? :confused:

allan907
29th Dec 2006, 11:33
'cos it doesn't know the words???

Foss
29th Dec 2006, 11:43
Not really applicable to a lake but..
Ice harmonies
Vibrations originating from an iceberg were recorded seismographically at the Antarctic Neumayer Station by scientists of the Alfred Wegener Wegener Institute for Polar and Marine Research and ‘Fielax’, a private business. The recorded vibrations produce harmonic sounds with up to 30 overtones. However, the sounds are not audible to the human ear because of the tones’ low register. The data might facilitate a better understanding of the processes in volcanoes where vibration patterns are similar.

Results might help vulcanologists
The scientists are analysing the results of their measurements in a study just published in the scientific journal Science. Initially, volcanic activity was thought to cause the low frequency vibrations; so-called ‘tremors’. However, comparisons of seismic soundings revealed movement of the source of the vibrations. By means of satellite imagery, a giant iceberg covering an area of 30 by 50 kilometres, was identified as the cause.

The researchers suspect that water flowing within the iceberg’s system of crevasses and tunnels, is stimulating elastic vibrations, similar to those of an organ pipe. “Understanding these recordings that are so comparable to volcanic tremors might in turn also help volcanologists to explain the causes of volcanic tremors”, surmises Christian Müller from Fielax GmbH. “In contrast to complex volcanic systems, icebergs have a simpler structure.”


You've got me interested now, and I'm going to drive myself nuts trying to work this out.
Fos

Buster Hyman
29th Dec 2006, 11:43
Is it like a "...DOOF, DOOF, DOOF.." noise?

Juud
29th Dec 2006, 11:44
I said ´sing´, not ´hum´. :8

Allan´s reading ability leaves a lot to be desired. He needs to try harder. Extra homework has been assigned, Headmaster will check his progress.

Foss, googling had gotten me that bit as well, and like you, I feel that it doesn´t apply here. Don´t do yourself (or idiot) an injury while figuring this out. :)

Buster, it´s not DOOF DOOF, the sound most resembling it is whale singing.
really it is. :ooh:

woolyalan
29th Dec 2006, 11:45
Can you record it and post it on the interweb?
or better still
Can we all come and have a listen?

sprocket
29th Dec 2006, 11:46
Maybe a wail is stuck under the ice? :hmm:

Foss
29th Dec 2006, 11:48
Is it 'Bring me sunshine' by Morecombe and Wise?

Juud
29th Dec 2006, 11:50
If it were stuck under the bluddy ice, we wouldn´t be hearing it would we Sprocket. :ugh: mumble... mutter ... grumble

Someone point me to a geologist froum please!

woolyalan
29th Dec 2006, 11:54
Just a guess, but, could it be the wind moving over the ice, after all, if wind on its own can make noises, why the hell cant it make different noises with ice? could be cooling air or something?

Still, try and record it for the world to enjoy :)

singaporegirl
29th Dec 2006, 12:00
Why does the ice sing?

Because it hears the cakewalk? :rolleyes:

I don't know the real answer to the question, but the phenomenon of singing sand (http://physicsweb.org/articles/news/10/7/5) is quite well documented.

sprocket
29th Dec 2006, 12:05
Well then, a new composition by "Icehouse"? Stuck penguins can also sing a song or two, although some are known to tap out a tune with their feet.

Does the noise produce harmonic sounds with up to 30 overtones? :p

Juud
29th Dec 2006, 12:06
ENGM 291100Z 291818 00000KT 0300 FZFG VV001 TEMPO 1806 4000 BCFG SCT001 PROB30 TEMPO 1806 -FZDZ BECMG 0610 18010KT 2000 SNRA BR BKN007 TEMPO 1218 4000 -RA BKN012

So wind´s out Wooly, but thanks for trying. :)
Got nothing here to record the sound with, but feel free to join us for a late lunch and a listen. :ok:

Ms SIN, I knew it´d be a woman wot spotted the pastry allusion! ;)
Sand singing sounds similar, but ice crystals seem to me a very different thing to sand grains, so....... ???

G-CPTN
29th Dec 2006, 12:08
When ice crystallises it has to expand. Large areas of water that are enclosed (such as a lake) have stresses and strains as the ice 'adjusts'. These are not plate fractures, but restructuring of the crystals. 'Pinging' sounds are frequently heard.

Or were the locals enjoying the newfound facility and expressing their joy in song?

GOLF_BRAVO_ZULU
29th Dec 2006, 12:19
Once water at sea level gets to 4 deg C it reaches its maximum density. As temperature reduces yet further, its density increases up to the formation of ice; which is why ice floats.

I suspect that it's the sound created by internal stresses as the ice forms that you can hear. Also, if the ice is thin, it's probably in a series of very thin layers that bend a small amount (not much, as water is incompressible but it will contain tiny air bubbles). Any undulations in the ice sheets may cause tiny screeches as they rub against each other.

My failure to provide an amusing answer is regretted; but I'm not alone.

Buster Hyman
29th Dec 2006, 13:09
Is it Vanilla Ice?

ShyTorque
29th Dec 2006, 13:17
I get this all the time.

It's just an ice song that you've heard before but can't quite put a name to.

;)

allan907
29th Dec 2006, 13:47
If it sounds like whales then the song must be..........







........"We'll keep a welcome in the hillsides, we'll keep a welcome.....etc"

:E

Howard Hughes
29th Dec 2006, 20:45
Are you sure it ain't Wayl-on Jennings...:E

sprocket
29th Dec 2006, 21:01
A long time ago I heard a rumour from that part of the world, 'the hills are alive with the sound of .... '

ExSimGuy
29th Dec 2006, 21:27
Could be Bob Marley, but without accompaniment, as I've heard that his Whalers are now being sued by GreenPeace

You thought you'd get a sensible response in here??? ;)

Aaaaaaaaaaaaaaaargh!
30th Dec 2006, 00:46
I think it's a form of refraction, so that any noise - ie vibration - such as a stone falling on the ise, or stress related noises gets propagated through the ice because it can't really escape. The event that caused the noise you're hearing could have happened many miles away :8

Keef
30th Dec 2006, 01:44
I haven't a clue. I liked the ice-sing bit (prefer marzipan, but lets not do that one).

I was thinking along the same lines - temperature stresses causing the ice to distort, and the noise that movement makes being transmitted into the air by the large diaphragm that is the ice sheet - which by now is probably above the level of the water in the lake.

If you bang on the ice with something suitable, does it reverberate?

OK - who's first with a picture of Juud, a mallet, and a frozen lake in the fog?

Rollingthunder
30th Dec 2006, 01:55
Now for a word of caution.

Don't throw stones onto the frozen surfaces of ponds or small lakes or pound on them. It will make an interesting sound but will kill the fish underneath.

Juud
30th Dec 2006, 09:53
ExSim, I got as I wanted. Few good ideas, few laughs. :ok:

The odd thing with the ice was how we´ve never heard it before, while it onviously freezes over every winter. Even checked with an elderly neighbour who has lived here all his life, and he´s never heard it before either.

Whole thing moot now, temp has risen to +5C and it´s raining merrily.

May I thank the gentlemen for their efforts. ;)

ExSimGuy
30th Dec 2006, 21:29
Some interesting input:

My daughter has a pond, about 60 cm in diameter. This does not sing.

Maybe an opportunity for research as to why this doesn't and your lake does?

:confused:

G-CPTN
30th Dec 2006, 21:43
Perchance the frequencies emitted by such a meagre 'pond' are outwith human audible frequency, whereas those of Juud's dimensions produce noticeable sounds?

I have experienced walking across several kilometres of sea ice, with sounds regularly being experienced, though some were due to the passing of vehicles (yes, really) and even distant ships (visible as they negotiated open channels, kept free of ice by their frequent passage).
I appreciate that Juud's observations were of a static unprovoked stretch of water, but I still suggest that these sounds are due to 'rearrangement' of the ice crystals during the formation process. As has been said, convection of the water before freezing occurs until a skin of ice forms, though beneath this skin, 'currents' persist as the density varies as the liquid water approaches freezing temperature. Crystal growth beneath the surface skin continues, and the change in volume of the fissures as they change from liquid to solid are sufficient to create 'heave' (albeit locally).
If you want to demonstrate the phenomenon in reverse, drop an ice cube into a glass of liquid . . .

Cron
30th Dec 2006, 23:25
Neighbours not heard it before .. but combination of fog and ice: frequencies present before but now fog modifying and presenting as human audible.

Strange things 'appen to sounds in fog.

They do in Birmingham. I lost all me Astra GTE 16v wheels in an overnight fog. Never heard a thing.

G-CPTN
30th Dec 2006, 23:32
But you had wheel-nut locks on them and had a hiding place for the lock-key . . .



. . . DIDN'T you?

Cron
30th Dec 2006, 23:45
No. I didn't.

I'm from Birmingham.

Learnt me lesson. But bloke down the pub says they can be gotten around silent like.

BOAC
31st Dec 2006, 12:51
If you bang on the ice with something suitable, does it reverberate? - not sure a chaplain should be suggesting that?:)

lexxity
31st Dec 2006, 13:00
Juud, you said it was foggy when it was singing. Obviously it is some wag sat in the fog with his whale music on full blast having a right good laugh at you all.:}

Rainboe
31st Dec 2006, 13:16
If you imagine the ice is like a drumskin, any minor vibrations produce a marked and amplified sound. I reckon the singing noise is various temperature changes in the ice, as it warms up in the sunlight, or cools down in the shade, and warms up from the water beneath, and indeed the junction between two areas warming and cooling probably causes stresses and strains which come through as short duration sounds. Put lots of these together and you would get sounds like a herd of hundreds of elephants all trumpeting producing quite a symphony if you could magnify it enough. You also get sounds coming through when the ice layer is not thick and someone walks on it. You can get long cracks appearing in the ice with peculiar noises that I can't even begin to describe. Would the singing only occur when the ice is still fairly thin? Thick ice would be strong enough not to do it. I'm sure it's internal tension producing stresses and strains Even small ice cubes make popping noises in warm water.

I miss the winters of old when we used to have freezing. Just doesn't happen in the south of England now.

tony draper
31st Dec 2006, 13:24
Probably a combination of chemistry geology and acoustics Mamasan,ice does indeed produce strange sounds these may well be amplified by the surrounding hills and reflected from the lake bed and Flappy towers could be located at a acoustic node.
On the othe hand it could be those feckin Trolls living under the bridge.
:rolleyes:

Juud
31st Dec 2006, 13:44
No no no Drapes, Trolls are very quiet during the Romjul; the well fed Nisser intimidate the hell out of them.

Since this is still on 'front page', here's some more info.
Bre very kindly sent me a perfect youtubelink. If you discount the sounds of cracks/boots/chainsaw and turn up your speakers, you can hear EXACTLY what's been going on here. :ok:
singing ice (http://www.youtube.com/watch?v=8VbyyhCscVc)


Rainboe, village kids used to take the frozen 'lake road' to get to school from about November until well out into spring. Crossing the lake (abt 2,5 miles by 0.5 mile) being much a shorter than going around it, obviously ;)
Haven't yet seen any kids on it this winter. :sad:
Also had a green Xmas this year, highly unusual in the past.
People in this part of Norway miss real winter as much as you do in the south of England.

Rainboe
31st Dec 2006, 15:35
It's green in Oslo too? This is getting scary. I'm skiing in 3 weeks. It has to stop now!
I'm certain it's cracking noises in the ice, not just from people walking on it, but temperature changes between the lower watery bits and the upper airy bits. Magnified by the large flat surface, with different horizontal speeds of sound through the ice and through the water. The 'pow' sound followed by a sound like a bullet passing nearby is cracking, and can be caused many ways. Lots of those, from all directions, and magnified by the drumskin, and you have a small orchestra!

frostbite
31st Dec 2006, 15:48
It's the sound of frogs that were mating and then found their bits trapped by the rapidly forming ice.

Aaaaaaaaaaaaaaaargh!
31st Dec 2006, 20:08
It's the sound of frogs that were mating and then found their bits trapped by the rapidly forming ice.That sounds like a night out with my ex-girlfriend :}

dontpickit
2nd Jan 2007, 17:28
From Henry Thoreau's Walden:

The cracking and booming of the ice indicate a change of temperature. One pleasant morning after a cold night, February 24th, 1850, having gone to Flint's Pond to spend the day, I noticed with surprise, that when I struck the ice with the head of my axe, it resounded like a gong for many rods around, or as if I had struck on a tight drum-head. The pond began to boom about an hour after sunrise, when it felt the influence of the sun's rays slanted upon it from over the hills; it stretched itself and yawned like a waking man with a gradually increasing tumult, which was kept up three or four hours. It took a short siesta at noon, and boomed once more toward night, as the sun was withdrawing his influence. In the right stage of the weather a pond fires its evening gun with great regularity. But in the middle of the day, being full of cracks, and the air also being less elastic, it had completely lost its resonance, and probably fishes and muskrats could not then have been stunned by a blow on it. The fishermen say that the "thundering of the pond" scares the fishes and prevents their biting. The pond does not thunder every evening, and I cannot tell surely when to expect its thundering; but though I may perceive no difference in the weather, it does. Who would have suspected so large and cold and thick-skinned a thing to be so sensitive?

frostbite
2nd Jan 2007, 18:02
Who would have suspected so large and cold and thick-skinned a thing to be so sensitive?



Sounds like some of the posters on JB!