A controlled ice spike growth experiment. The frame rate is about 50X normal time. The air temperature was -11.5C and the grid squares are 1 mm. The colours that appear on the ice surface toward the end of the video are potassium permanganate crystals sprinkled onto the ice. It looks as if there is evidence of a liquid layer on the surface, suggesting (though not conclusively) that there is some overflow at the spike orifice near the end of its growth. Movie made in the ice lab of Edward Lozowski at the University of Alberta. Movie by Lesley Hill, Russ Sampson and Edward Lozowski, with technical help by Kenny Lozowski.

See

www.physics.utoronto.ca/~smorris/edl/icespikes/icespikes....

Tags:   pattern formation patternformation emergence ice spike movie time lapse icecube

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Why do ice cubes grow spikes?

The short explanation is this: as the ice freezes fast under supercooled conditions, the surface can get covered except for a small hole. Water expands when it freezes. As freezing continues, the expanding ice under the surface forces the remaining water up through the hole and it freezes around the edge forming a hollow spike. Eventually, the whole thing freezes and the spike is left.

A slightly longer explanation: the form of the ice crystals depends on the cooling rate and hence on the degree of supercooling. Large supercooling favors sheets which rapidly cover the surface, with some sheets hanging down into the water like curtains. These crystalites tend to join at 60 degrees and leave triangular holes in the surface. Hence, spikes often have a triangular base. The sides of the spike are sometimes a continuation of pre-existing subsurface crystalites, and can extend from the surface at steep angles.

See

www.physics.utoronto.ca/~smorris/edl/icespikes/icespikes....

Photo by Mary de Bruyn

Tags:   pattern formation patternformation emergence icecube ice spike

© All Rights Reserved

Why do ice cubes grow spikes?

The short explanation is this: as the ice freezes fast under supercooled conditions, the surface can get covered except for a small hole. Water expands when it freezes. As freezing continues, the expanding ice under the surface forces the remaining water up through the hole and it freezes around the edge forming a hollow spike. Eventually, the whole thing freezes and the spike is left.

A slightly longer explanation: the form of the ice crystals depends on the cooling rate and hence on the degree of supercooling. Large supercooling favors sheets which rapidly cover the surface, with some sheets hanging down into the water like curtains. These crystalites tend to join at 60 degrees and leave triangular holes in the surface. Hence, spikes often have a triangular base. The sides of the spike are sometimes a continuation of pre-existing subsurface crystalites, and can extend from the surface at steep angles.

See

www.physics.utoronto.ca/~smorris/edl/icespikes/icespikes....

Photo by Miles Chen

Tags:   pattern formation patternformation emergence spike ice icecube

© All Rights Reserved

Why do ice cubes grow spikes?

The short explanation is this: as the ice freezes fast under supercooled conditions, the surface can get covered except for a small hole. Water expands when it freezes. As freezing continues, the expanding ice under the surface forces the remaining water up through the hole and it freezes around the edge forming a hollow spike. Eventually, the whole thing freezes and the spike is left.

A slightly longer explanation: the form of the ice crystals depends on the cooling rate and hence on the degree of supercooling. Large supercooling favors sheets which rapidly cover the surface, with some sheets hanging down into the water like curtains. These crystalites tend to join at 60 degrees and leave triangular holes in the surface. Hence, spikes often have a triangular base. The sides of the spike are sometimes a continuation of pre-existing subsurface crystalites, and can extend from the surface at steep angles.

See

www.physics.utoronto.ca/~smorris/edl/icespikes/icespikes....

Photo by Miles Chen

Tags:   pattern formation patternformation emergence ice spike icecube

© All Rights Reserved

A spontaneous ice-spike like formation at the foot of a weir on a natural stream in south central North Dakota.

Bubbling sounds were heard emerging from the top. Observed by Dennis Rosenkranz and Nathan Stroh, Winter 2011.

See
nd.water.usgs.gov/sw/icespikes.html

It appears that the stream freezes over completely and then later additional flow forces water upward through a crack. The new water partly freezes when it emerges, forming a messy tower of ice. Subsequent water comes out near the top of the tower, adding to it.

Something similar is sometimes seen in your fridge when the expansion due to freezing drives water up forming an "ice spike". See
www.physics.utoronto.ca/~smorris/edl/icespikes/icespikes....

Posted with the kind permission of
U.S. Geological Survey
Department of the Interior/USGS

Photo by: Nathan Stroh/USGS

Tags:   formation patternformation pattern nonlinear nature emergence icicle ice

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