David Pescovitz on January 21, 2010 2:53 PM
Hair ice
No, that's not a hairy branch but rather an astounding kind of ice formation called "hair ice" ("haareis" in German). Illinois State University professor James Carter of the Geography-Geology Department, created a page about this natural wonder that includes many photos of these marvelous ice growths, sometimes called "silk frost" or "cotton candy frost."The photo above is by Rick Eppler of Vancouver Island, Canada. From Carter's "Ice Formations on Dead Wood" page:
While the term frost is used frequently as part of such names, these ice formations are not a product of frost. Frost comes about by moisture from the air being deposited on surfaces. As such frost is quite amorphous and would never appear as fine needles like we see here. Hair Ice is ice that grows outward from the surface of the wood, as super-cooled water emerges from the wood, freezes and adds to the hairs from the base.
"Ice Formations on Dead Wood -- Haareis or Hair Ice" (via MAKE:)
Ice Formations on Dead Wood -- Haareis or Hair Ice
Dr. James R. Carter, Professor Emeritus
Geography-Geology Department
Illinois State University, Normal, IL 61790-4400
In 2006 Geoff Gaynor of Wales sent me an email with photos of some ice formations he had observed. Those photos appear on the master page. Geoff had seen my web pages and wanted to know what he had found. The ice in his photos was similar to my ice flowers but is on woody material on the ground. I think Geoff was the first person I asked if I could use his photos on my web pages. Geoff gave me permission and that set a direction for these pages. Thus, I have been able to show interesting formations of ice that I have not seen. This is particularly true of Hair Ice featured here which I have yet to see.
Subsequently I have learned that this form of ice is called Haareis or Hair Ice, in German and English. That name is most appropriate describing the hair-like nature of those fine needles. This photo by bobbi fabellano from the Olympic Peninsula of Washington, USA, shows this hair-like texture. Note that in this and other photos, the hairs of ice do not grow from linear fissures in a stem but rather appear to come out of pores in the wood. As such they are similar to hair on a head.
In the photo above there appears to be no bark on the piece of wood. The photo below shows ice growing only where there is no bark. It has been suggested that the growth of ice may push out and break off old bark. This photo was taken by Joachim Mittendorf in the Harz Mountains of Germany. That location is significant because in 1884 Prof. Schwalbe described similar ice he found in these same mountains
Mittendorf in an email of March 2007 wrote: "Most of the numerous white branches had very thin and up to 3 cm long "hairs." They really looked like the thin white hair of a human being." Here the 'hair-like' nature of this ice is quite evident and the comparison to white hair of human beings is appropriate.
Below is another photo of Haareis or Hair Ice from Joaquim Mittendorf. I included this photo because it is different from the other photos in that it shows a dense array of ice but the individual hairs of ice are still distinct. Note that in this photo the ice is on a dark piece of wood and that below that piece of wood we can see daylight reflecting off the leaves. This demonstrates the wood does not have to be on the ground.
In her email to me bobbi fabellano called this type of ice "silk frost," a name she heard from others, She proposed the name "cotton candy frost" which is quite appropriate in many ways. While the term frost is used frequently as part of such names, these ice formations are not a product of frost. Frost comes about by moisture from the air being deposited on surfaces. As such frost is quite amorphous and would never appear as fine needles like we see here. Hair Ice is ice that grows outward from the surface of the wood, as super-cooled water emerges from the wood, freezes and adds to the hairs from the base.
The photo below is from bobbi fabellano who found this on the Olympic Peninsula, Washington, USA. This photo portrays an array of ice like a flower. Much of the appeal of this photo is the color at the center which is from the diffusion of sunlight.
Compare the ice in this photo with that below, from Rick Eppler of Vancouver Island, Canada. In both cases the ice seems to emerge and spread out from a central area. In both cases the needles or hairs of ice stay as individual strands while the growth of ice from plant stems more commonly fuse together to form ribbons or continuous surfaces.
Rick Eppler is also the source of the photo below. Both of these are from Vancouver Island on the west coast of Canada. This is very close to the area in Washington where bobbi got her photos. I included both of these photos because they are very attractive and give great insight into this form of ice.
While I have argued that Hair Ice does not fuse together like Ice Ribbons or Ice Flowers that grow from plant stems, the two photos below from Rick suggest this is not always the case. In these two photos the ice does seem to form a ribbon. As I have studied these photos, I think they may be of the same growth of ice.
In this series of web pages showing the growth of ice with diurnal or daily freeze/thaw activities, we see ice growing from pieces of dead wood, from plant stems, from soil and from rocks. This ice has a common base but the form varies with the media from which it grows.
Haareis or Hair Ice from the Past
The first reference I know about this type of ice growths appeared in a report on the meeting of the Physical Society in Berlin, in the March 13, 1884, issue of Nature Prof. Schwalbe describes flowers growing from rotten twigs lying on the ground in the Harz Mountains as ". . . ice-excrescences of soft, brilliant, asbestine appearance, and uncommonly delicate to the touch. . . ." Prof. Schwalbe brought some of these withered and rotten twigs with him toBerlin, and it was in his power to produce on them at any time the phenomenon just described. For this purpose all that was needed was thoroughly to moisten the twig, in such a manner, however, that no water dropped off, and then to let it cool slowly in a cold preparation. Ice-excrescences also appeared of themselves on twigs lying in the garden whenever the temperature fell below 0 degree C. in the night." (p. 472)
In a later editions of Nature there were a series of letters reporting on ice formations and reacting to earlier letters. Most of these reports relate to what was obviously needle ice but in the January 1, 1885 issue B. Woodd Smith tells of a friend who ?. . . picked up a piece of a dead beech-branch which was covered with filamentous ice, such as is described by the Duke of Argyll and others.? This person found the ice reappeared again the next morning when it was left out over night. (p. 194).
Prof. Alfred Wegener in 1918 in Die Naturwissenschaften (6/1, pp. 598-601) wrote about seeing this type of ice in two different places. In the article entitled "Haareis auf morshem holz" he had three photographs and two sketches. Wegener hypothesized a connection between the formation of the ice and the presence of fungi. This is the climatologist Wegener who went on to fame for proposing the concept of Continental Drift.
A. Hillefors wrote about ?Needle Ice on Dead and Rotten Branches? in Weather, 1976 (31, pp. 163-168). He observed Haareis in Sweden and notes the ice occurred on branches of beech. Hillefors as a meteorologist attempted to relate the formation of the ice to the synoptic weather preceeding the event. We now know it is more a product of diurnal freeze/thaw, which may occur under many synoptic weather situations. Hillefors noted that when such ice forms in soil it is known as "pipkrakes" in Sweden and as "kammeis" in Germany. He considered his ice on beech to be a peculiar form of pipkrakes, or a variation of Needle Ice. Indeed, it is in the sense that it is another form of the growth of ice with diurnal freeze/thaw processes. Hillefors referenced only an 1880 report by the Duke of Argyll about ice on plant stems and missed the papers by Schwable 1884 and Wegener 1918 on Haareis in Germany and France.
So, this is far from a new phenomenon. In spring 2007 I received an email from Joachim Mittendorf in Sweden with a photo of a similar occurrence of ice on wood he saw in the Harz Mountains of Germany, where Prof. Schwalbe saw ice more than a century earlier. I was beginning to believe that Haareis occurred only in Europe until I received the photos from bobbi fabellano in the Pacific Northwest. Then I heard from Brenda Callan and Rick Eppler, both from coastal British Columbia, Canada. As a geographer I want to know where each type of ice is found. Thus it appears that Hair Ice is found only in the Pacific Northwest part of North America and western Europe.
And speaking of geography, someone put me on to two photos of such ice formations on the Geograph web site in the UK where the goal is to have photos from every grid square. The links to these photos are http://www.geograph.org.uk/photo/320718 and http://www.geograph.org.uk/photo/320726 These two photos are from near Inverness, Scotland. There is no doubt these photos are showing the same type of ice seen in Wales, Germany, Sweden and the Pacific Northwest of North America.
As spring 2008 approached I received a gold mine on this type of ice formation. Gerhard Wagner of Switzerland pointed me to web pages showing many views of such formations and to two of his articles available as pdf files at http://www.wagnerger.ch/daten/haareis.pdf and http://www.wagnerger.ch/daten/haarstaengel.pdf
The more comprehensive article is that of Gerhart Wagner and Christian Matzler, "Haareis auf morschem Laubholz als biophysickalisches Phanomen" or "Hair Ice of Rotten Wood of Broadleaf Trees -- A Biophysical Phenomenon" This 31-page paper is downloadable from http://www.iap.unibe.ch/publications/download/3152/de/ The paper is in German with an English abstract and contains many photos and diagrams which add insights. The captions are in both German and English.
Wagner and Matzler, 2009, "Haareis -- Ein seltenes biophysikalisches Phanomen im Winter" Naturwissenschaftliche Rundschau, 62, Heft 3, pp. 117-123, is the definitive paper on this topic. Summarizing the current state of knowledge they state they have found Haareis on wood from beech and oak, and reference others who have found such ice on hazel wood, maple and alder pieces. Note that all of these are deciduous trees.
There are some good images on a number of web sites. Der Karlsruher Wolkenatlas has five photos of Haareis. The Natur Galerie von Paul Esser has a nice collection of photos, #2 of which is Haareis. It is my interpretation that the ice in this photo is not as long as in many photos, but in this example the wood seems to stand vertical and may be part of a tree that still has some life. The Waldwissen.net web site has two photos of Haareis on pieces of wood on the ground. In these two photos the threads of ice are much longer than in other images I have seen.
Then I received a photo from the Netherlands showing a good example of Haareis. So, another country in Europe is home to these ice formations. Interestingly, a few weeks before I had received photos from the Netherlands of Ice Flowers on plant stems. Those are the first examples of Ice Flowers I have seen from Europe.
Thank goodness for the Internet and digital cameras for they let us exchange information about these attractive ice formations. Please take on the task of looking for ice when the freeze/thaw processes are underway. Feel free to contact me at jrcarter@ilstu.edu if you see any ice of this nature in your early morning outings.
Return to the master page of Ice Formations with Diurnal Freeze/Thaw Cycles
One of the many web pages of Dr. Jim Carter
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