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|Avalanche has been listed as a level-4 vital article in Science. If you can improve it, please do. This article has been rated as B-Class.|
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- 1 Avalung
- 2 Changes
- 3 Prediction
- 4 Slab vs. point-release
- 5 Snow-crystal structure
- 6 Debris avalanches
- 7 The Group
- 8 Large portion removed has been put back
- 9 Yelling
- 10 Death
- 11 Additional Picture
- 12 "Gravity Current" removal
- 13 "Mobile phone interference with transceiver?"
- 14 Avalanche survival
- 15 So Helpful!!!!!
- 16 That is awesome
- 17 Recent Edits
- 18 GPS
- 19 Completely biased article
- 20 Picture of slab avalanche
- 21 How to
- 22 Southern Hemisphere has avalanches too!
- 23 Further work to do
- 24 WikiDisaster Project
- 25 Unscientific!
- 26 Incorrect Caption
- 27 Other Errors
- 28 Major strangeness
- 29 Serious, unscientific errors
- 30 Serious, unscientific errors
- 31 Avalanche avoidance
- 32 Classification and terminology
- 33 Avalanches as critical phenomena
- 34 Failure modes
- 35 Very basic cleanup completed
- 36 Separating avalanche rescue topics
- 37 Incorrect photo label
- 38 Three Part Description
- 39 Dynamics
- 40 Rutschblock
- 41 Page restructuring
Not a vandal. I started revising this article and making corrections. I also added a few new topics, such as Avalanche Rescue an Avalanche Triangle, so that information that does not belong in the Avalanche article has an appropriate location. Most avalanches do not involve people; therefore rescue doesn't need to be discussed in the Avalanches article. Also, a lot of the text in the Avalanches article applies to backcountry recreationists. There should be a separate article for the Avalanche Triangle as well. —Preceding unsigned comment added by Somerandomicicle (talk • an avalache can kill people on the slopescontribs) 04:06, 11 February 2009 (UTC)
- The changes were reverted by a bot - please report it here if the revert should not have been made Camw (talk) 04:08, 11 February 2009 (UTC)
Heeloo. This article could use sections on prediction (to go with the table), protection, how to survive, and what non-buried witnesses should do immediately. Maybe also a list of the world's greatest avalanche disasters? or is there a better place for that? Lupinelawyer 18:12, 14 Feb 2005 (UTC)
Slab vs. point-release
I think more attention should be given to the table of avalanche sizes, the one that starts off with "sluffs" as being the smallest and least dangerous avalanches. Sluffs are actually another term used to describe point-release avalanches and has nothing to do with its size or destructive capacity. These sluffs are usually a very good indicator of top-layer snowpack instability. You should avoid slopes with aspects that are sluffing. The other kind of avalanche is a slab-release avalanche, which usually occur when there are deeper instabilities in the snowpack, such as buried layers of hoar, facets, and round snowflakes. Generally, slab avalanches are much bigger than point-release ones, but that doesn't mean sluffs pose virtually no risk to humans. There have been some big point-releases that dwarf smaller slab avalanches. In fact, the misconception that point-releases are not harmful might lead some backcountry travelers to believe that it's safe to travel on aspects where these are ocurring, when in reality point-releases are one of the red-flags travelers should look out for. Aspects that are sluffing are on the verge of sliding big-time and should be avoided!
Usually the "size" of avalanches in the US is measured by their destructive potential rather than the volume of snow moved. Since you could have a really wide slab release that only falls a half-meter that might knock someone to the ground that would have the same volume as a much more destructive avalanche that's only half a meter wide and falls much further and takes out a bunch of trees, understanding the destructive potential is much more important than volume of snow moved. I forget what the rating system is but it's in the "Avalanche Handbook" that's already cited and starts with little ones that bareley move any snow to the biggest which can derail a train. I don't have the book anymore or I'd post the information up myself.
Maybe some basic stuff about snow-crystal structure and formation, and maybe how this relates to snowpack stability?
The article is incorrect about debris avalanches, which usually have nothing to do with snow. Unfortunately, debris avalanche redirects to this article. Either a new article should be started or a lot more information should be added to this article. -- Kjkolb 02:53, 19 March 2006 (UTC)
Consider changing this section to something like Avalanche Management, because the sub-sections fall under a broader category of managing a group in avalanche terrain.
The subsection called Traversing should be renamed Terrain management and broadened. Traversing is both too vague and too specific. The Terrain management section should briefly mention not under cutting slopes (removing physical support), not skiing over convex rolls, and staying away from weaknesses like exposed rock. Also mention avoiding terrian traps (gulleys that can be filled in, cliffs over which one can be swept, or heavy timber into which one can be carried). Basically this sub-section explains reducing the risk for the individual skier on a slope.
The subsection on Risk should be renamed Group Managment and would explain reducing the overall reduction of risk for a whole group by using strategies such as exposing only one memberat time to a hazard, having well defined safe spots, and planning escape routes.
The Group size section is close to correct. It should strongly emphasize that a carefull balance needs to be struck between having enough people to carry out a rescue (sometimes 2 is enough) and having far too many people to safely manage the risks.
The Leadership sub-section is way off base and needs to be completely re-written. Leadership in avalanche terrain requires well defined decision making protocals, which are being taught in a growing number of courses provided by national avalanche resource centers in Europe and North America, and an honest attempt at assessing ones blind spots, (what information am I ignoring?) There is a growing body of research into the pyschological failures and group dynamics that lead to avalanche involvement, could some of that be referenced? -- Aaron
- You can make these changes yourself, if you want to. It was good to post your concerns to the talk page, though. You might want to get an account before making major changes, as it will help communication with other editors and will make it less likely that your edits will be confused as vandalism (for example, editors might get suspicious when you delete a section that needs to be rewritten). You don't have to give any personal information to get an account, not even an email address (you can give an email address if you want to receive mail from other editors, though). Whether you get an account or not, be sure to give descriptive edit summaries about the changes you make. Giving references would also be a good idea. -- Kjkolb 17:43, 9 May 2006 (UTC)
Large portion removed has been put back
Wow, since August 2, 2006 this article underwent, what appears to me, erroneous editing.
I made a contribution to the pictures on this page and when I was looking back at the article and noticed that a significant portion of it was removed. I'm not certain removing that much information was intentional. So I took the liberty to EDIT the article on August 1 by Kjkolb and saved the changes to be current.
- Nope. Or - to be exact:
- You can trigger avalanches by really powerful sounds, like an explosion, but yelling has not enough energy.
- Its extremely improbable (what I mean by improbable: there is also a risk of a sudden avalanche triggered by a meteorite fall...). --Wikimol 00:01, 22 November 2006 (UTC)
- Vibrations actually cause the most Avalanches. —Preceding unsigned comment added by 220.127.116.11 (talk) 17:32, 7 April 2008 (UTC)
How do people die in avalanches do they suffucate or die of the cold? DPM 22:24, 12 December 2006 (UTC)
- Good question. Someone deleted the answer to this question, along with other material, on December 7. I restored it just now. The article says, "most deaths are due to suffocation". Walter Siegmund (talk) 00:19, 13 December 2006 (UTC)
I have made the addition of a picture of avalanche blasting in Tignes and was wondering if more depth could be added to the section on prevention which covers the use of explosives to trigger deliberate and hopefully controlled avalanches - as it is method that almost any skier is subject to who has visited the mountains when there’s a lot of snow around.
"Gravity Current" removal
The following statement is inaccurate: "An avalanche is an example of a gravity current consisting of granular material." Gravity currents consist of very low aspect ratios involving differing densities, typically when more saline water displaces less saline water, or differing air densities. It does not apply to snow on a mountain! Removed. - Mugs 23:43, 20 January 2007 (UTC)
You're wrong. The powder cloud in a powder snow avalanche is a turbulent suspension of particles that is a form of gravity current. —Preceding unsigned comment added by Jim McElwaine (talk • contribs) 00:00, 5 September 2007 (UTC)
"Mobile phone interference with transceiver?"
At least needs a citation. I have not seen any documentation of this concern. DriveBy27 01:07, 29 January 2007 (UTC)
18.104.22.168 00:34, 30 January 2007 (UTC)i read a book where a 14 year old lived for a week before almost dying. is that possible? jamie
- No, it is not possible. When children turn 14, they die immediately. In case any young children are reading this, that was a joke. I assume that you mean can a person live for a week after being buried by an avalanche. The chances of survival drop quickly in the first hour and after a couple of hours, the survival rate is very low. However, if the person has enough air and has clothes that are sufficiently warm to avoid hypothermia, I suppose it might be possible. If the person is able to climb out after being buried, it would be difficult for him or her to survive for a week without food, water, supplies or training, but he or she would be far more likely to survive than someone who is buried. -- Kjkolb 09:21, 30 January 2007 (UTC)
I live in Texas, where avalanches don't happen, but I was so interested in this site. I am in 7th grade and doing a project over avalanches (blind draw) and I found all this stuff so helpful. I learn so much from this site and it helped me so much with the project. Thanx!! —The preceding unsigned comment was added by Bandgeek3377 (talk • contribs) 01:14, 2 February 2007 (UTC).
That is awesome
Good to hear that this kid really appreciates Wikipedia. It's a nice spring board for other sources, and in and of itself is pretty nice as well.
I also wanted to say, to the lame imbecile who posted emoticons in the Avalanches article, that you are completely insane. I mean, yes, I am totally bonkers, but you... smiley faces on a Wiki page? I mean, can you not think of anything more creative? And anyway, you're just wasting our time. It's funny that people who are stupid enough to vandalize a page are smart enough to find the Web site in the first place... it makes you wonder, are they really *smart* deep down inside?
Nearly a year ago I made some recommendations. I'm finally getting around to them. I've referenced Pascal Hageli when discussing avalanche rates for terrian and aspect, although I can't remember the exact article, I'm going off my notes from the November 2004 Avalanche Workshop at the University of Calgary. It has been a great ski season so far - Aaron --Insightaction 23:30, 7 March 2007 (UTC)
I replaced "With modern mobile phone developments, an emergency GPS transmitter may also become more widely available (again, for use by a rescuer, because a victim may be unconscious or completely immobilised beneath dense snow)." by "Alternatively, survivers may use a mobile phone to notify emergency personnel of their location obtained from a GPS without EPIRB capability." The original seemed unclear to me. Walter Siegmund (talk) 16:18, 19 September 2007 (UTC)
Completely biased article
This article is completely biased in favor of snow avalanches. Article rock avalanche redirects to this page so there should be far more than passing mention of them. --TreeSmiler (talk) 23:17, 27 January 2008 (UTC)
- I disagree. Snow avalanches are a totally different topic from rock, dirt or mud avalanches. Those are covered in Landslide. I'm going to change the redirect to point there. ·:· Will Beback ·:· 23:58, 27 January 2008 (UTC)
- If so, it should be straightforward to identify reliable sources that distinguish the phenomena. Please be kind enough to suggest some. Thank you, Walter Siegmund (talk) —Preceding comment was added at 04:49, 2 February 2008 (UTC)
- I was confused by this as well. The American English definitions of the word "avalanche" that I can find do not specify snow as being the primary constituent. This article is clearly only about snow avalanches. I believe either the article title should be changed to "snow avalanche", or at least, a statement at the top should specify that other avalanche types are covered in the "landslide" article. Krellkraver (talk) 05:01, 15 April 2012 (UTC)
Picture of slab avalanche
The third picture from the top is not characteristic of a slab avalanche. Most slab avalanches do not have a cloud of snow above them. That is usually common from a sluff avalanche. Isn't that picture misleading when captioned as a slab avalanche? Billscottbob (talk) 03:42, 8 February 2008 (UTC)
- From having seen numerous videos of avalanches, it's correct that the beginning of a slab avalanche would not necessarily be marked by a cloud of snow. However that image appears to show the bottom of a slope, by which time the slab would have broken up. In any case, it's not a good picture of a slab avalanche as it doesn't show the characteristics of one. I'm going to remove "slab" from the caption. ·:· Will Beback ·:· 22:23, 14 November 2008 (UTC)
This article needs complete revision as there are many mistakes in the text. I also suggest to change the title to snow avalanches, as there are many different types of avalanches. The Avalanches can be also made of rocks and Dirt.
You should also have information on:
- Wikipedia is not a manual, guidebook, or textbook. -shogun (talk) 20:41, 7 April 2008 (UTC)
- It's also legally risky to instruct people on how to do live-saving things that should be learnt in a formal course.Billscottbob (talk) 21:55, 14 November 2008 (UTC)
Southern Hemisphere has avalanches too!
I've edited the text to refer to the "sunny" side of slopes... The previous reference to southern slopes only works north of the equator! 22.214.171.124 (talk) 07:19, 27 December 2008 (UTC) Mike Bromfield / 27 Dec 2008.
Further work to do
Any objections to adding a section called Triggers under Formation and Occurrence. This would present environmental and human triggers of avalanches.
I would also like to take a large part of the second paragraph of the introduction and put it under a formal subheading of Formation and Occurrence called Classifications and Terminology. This would present terms like, step down avalanche, crown, slide path, run out, debris field, etc... I think this should be the first section under Formation and Occurrence.Insightaction
- Sure, be bold and give it a try. If someone doesn't like it they may revert your work, but usually good faith improvements are appreciated and accepted. It helps if you provide a WP:RS or two. BTW, you can sign your comments (talk pages only) by ending with "~~~~" (four tilda characters). Walter Siegmund (talk) 03:56, 29 January 2009 (UTC)
i think they should do a section on all the prevent, protect and predict. as many people reli on wiki to do school projects and thats part of the criteria!126.96.36.199 (talk) 17:29, 28 November 2009 (UTC)
- I don't think that's necessary; Wikipedia is not a study guide, it's an encyclopaedia. As such, the current sections are probably better suited. (Although some merging of the "Euro Risk"/"Euro Size"/"NA Danger" sections could be useful).
- Oh, and yea, I noticed that that comment was over a year old. Still. XD Crashdown13 (talk) 12:09, 28 September 2011 (UTC)
It is time to improve the prevention-aviodance-rescue sections to bring them into compliance with the WikiDisaster Project. I propose:
1. Create a new section before Dynamics and Modeling called Disaster Management
2. Create subsections corresponding to Prevention, Mitigation, Preparedness, Response, Recover
3. Move the content in the sections prevention-avoidance-rescue into the appropriate newly created subsections
Basically the sections need an over haul to reduce redundancy, and improve clarity
- We need to avoid making this into a "how-to" manual. I'm not sure that those headings are the best ones for this article. There is a considerable volume of scholarship on avalanches, and it seems like it'd be better to use the terms that appear in the literature rather than terms developed by the Wikipedia:WikiProject Disaster management editors to cover all different disasters. For example, response and recover would perhaps be better covered by a heading like "rescue". "Prevention" isn't really a practical heading, but "avoidance" would be a comparable term that's closer to the reality. Will Beback talk 22:51, 2 November 2010 (UTC)
I found a more approipate place for the wiki disaster material, under the sub-article of avalanche control. But now I would like to propose restructuring this article to make its context within the broader wiki themes clearer. I propose the following main sections:
Introduction: what is an avalanche?
Meteorology: what weather is needed to create an avalanche? Where does a snow pack come from and how does it evolve? how are they studied in the context of meteorology?
Geography: how do you identify avalanche terrain? what hazards do avalanches pose to people and places? how does terrain affecting avalanches and how does avalanches affect terrain? the study of...?
Geology: What type of geology is needed? is it always mountains? Can avalanches affect geology? the study of...?
Disaster Management: how are avalanches prepared for? how are avalanches forecast? what are the responses to avalanches? what equipment and techniques are used? the study of...?
History: what are the notable occurrences? wartime use of avalanches? recent news worthy avalanches? the study of...?
- I guess I don't understand the need for this reorganization. Could you explain what's wrong with the current article? Will Beback talk 22:07, 16 November 2010 (UTC)
- Sure, I think the article should succinctly describe avalanches, their formation, characteristics, properties, and occurrences. It should also fit into the broader context of the developing wikiprojects around Geology, Geography, Meteorology, and Disaster Management. The article over emphasizes the human reaction to avalanches, which should be in its own article on Avalanche Control or Management. The topic of humans and avalanches is currently developed in this article at the cost of elucidating the physical characteristics and natural relevance of avalanches. Sections like avalanche avoidance, survival/rescue, and Modeling only are applicable within the context of avalanche management. Succinctly my argument is that the main article on Avalanches should be a starting point from which to explore the other topics related to avalanches. I have two Google documents with proposed outlines for a major revision of the Avalanche article, and additions to the Avalanche Control article
- feel free to drop ideas in those documents. (also, because Wikipedia is the first point of contact for many public searches, I want to make the article more attractive and elegant)
- If you think that the article is long, then I agree that a logical split would between the issues of how avalanches are caused and how humans avoid or react to them. But I am dubious about organizing the article according to generic wikiproject templates instead of reliable secondary sources. This is a very well-researched topic. For example, geology is a negligible factor so I don't see why we'd devote much space to the type of rocks in the slopes. Will Beback talk 01:01, 18 November 2010 (UTC)
- In particular, I think that "prevention" is not a logical heading and that "social intervention" is also odd. Will Beback talk 01:58, 18 November 2010 (UTC)
- Is there a better heading for topics about education and awareness, public bulletins, forecasts and warnings? These are all activities avalanche centers undertake to lessen the hazard of avalanches, by motivating users to decrease their own exposure to high risk avalanche situations, particularly in the context of recreational use of avalanche terrain.Insightaction (talk) 04:25, 18 November 2010 (UTC)
- Insightaction; I can't tell from your edit history whether you are aware of article quality levels. If not, those criteria and associated peer reviews may be helpful in your work. Walter Siegmund (talk) 02:31, 18 November 2010 (UTC)
- I'm working out of the books by Daffern, McLung, and Jamieson, materials from Parks Canada, and what is now called the AST I & II courses offered by the CAA, as well 25 or so peer reviewed works for, however much the peer reviewed publications is at the edge of verified knowledge and is probably not appropriate in this setting.Insightaction (talk) 03:56, 18 November 2010 (UTC)
- Thank you Will, I will back off on the aggressive changes until I hear back from the professional avalanche community. I have sent a request to my contacts in the CAA and guiding industry in Canada to have some professional oversight of my contributions, hopefully I can get some feedback. In the meantime I can beef up the literature search and sprinkle references through my outlines like magic pixie dust. Part of the problem is that I was first exposed to this material more than 15 years ago, so there has been a long period of digestion and reorganization, to the point where it is hard to tell where one or another piece of information is from. What I would like to accomplish is to take the rather technical industry orientated scholarship, that I had to personally study, and place it in a context that is accessible to the broader public; thus when I write I imagine explaining the topic to an undergraduate in Texas, or some other location that rarely sees snow. In a way I write for myself, because I personally use Wikipedia to find how to get started in a topic.
"The triggering of avalanches is an example of critical phenomenon."
The reference for this IS NOT cited. Furthermore, research by Dave McClung ( whose work is cited elsewhere in the same Wikipedia article ) presents avalanches as an example of a punctuated equilibrium system. His work is excellent: http://www.geog.ubc.ca/avalanche/pubs/Book_Tsonsis_Ch24.pdf — Preceding unsigned comment added by Thermodynamic (talk • contribs) 07:31, 19 December 2011 (UTC)
The caption containing the text "A powder snow avalanche" isn't correct. The correct term for the avalanche featured in this photo is "Dry snow avalanche with a powder cloud". Thermodynamic (talk) 04:14, 20 December 2011 (UTC)
"A rapid rise in temperature, to a point significantly above the freezing point of water, may cause a slope to avalanche, especially in the spring."
This is poorly written and partially wrong. Should be written as follows:
"A rapid rise in temperature, to a point significantly above the freezing point of water, may cause avalanche formation at any time of year."
"Cold air temperatures on the snow surface produce a temperature gradient in the snow, because the ground temperature at the base of the snow pack is close to freezing; unless the snow pack is standing on glaciated terrain, in which case the temperature at the base of the snow pack can be significantly below freezing."
There is always a temperature gradient. The text should read:
"Very cold air temperatures on the snow surface produce a strong temperature gradient in the snow because the ground temperature at the base of the snow pack is usually around zero degrees and the ambient air temperature may be much colder."
"The snow pack is composed of deposition layers of snow that are accumulated over time. The deposition layers are stratified parallel to the ground surface on which the snow falls."
This should be written:
"The snow pack is composed of layers of snow that are deposited over the course of a winter. These layers exhibit ground-parallel stratigraphy."
This is pure garbage:
"A "wind slab" is a particularly fragile and brittle structure which is heavily loaded and poorly bonded to its underlayment."
It should be written:
"Wind slab is dangerous because it forms quickly and weaker snow below the slab may not have time to adjust to the new load."
But... really... wind slab is only dangerous relative to humans and facilities. It's just a natural phenomenon, and using the word "dangerous" biases the discussion toward human/avalanche involvements.
"This can occur in two ways: by top-loading and by cross-loading."
This is a ---gross--- oversimplification. Patterns of loading and drifting are very complex.
"Sunlight reduces the sintering, or necking, between snow grains. "
This should be written as:
"Sunlight melts snow, which decreases its hardness."
"and other sudden impacts"
Should be written as:
"and other impulse loads"
Finally, there is a lot of discussion of human involvement with avalanches that biases the article toward human-avalanche interaction. These biases should be explicitly disclosed or the topics should be separated. Avalanches are natural phenomena, and this article should focus on the phenomena, not on human involvement.
This was just a quick review. There are numerous errors and a disturbing lack of citations. 26 citations??? Considering the foregoing, this article borders on being unscientific.
- Anyone is allowed to make changes and someone who really knows the subject and can provide missing citations is particularly welcome. However, discussing major changes in advance is always a good idea. Mikenorton (talk) 08:14, 19 December 2011 (UTC)
Not only is the section "Classification and terminology" badly written, it does not conform to the scientific literature.
From "The Avalanche Handbook". There are two main type of avalanches:
- Slab avalanches - Loose snow avalanches
I'm talking about stuff like: "isothermal avalanche". Nowhere in the literature of avalanches is there any discussion of "isothermal avalanches". Isothermal snow means snow with a uniform temperature, usually in the spring when the ambient air temperature remains above freezing over the course of a week or two. This is just one example of the incredibly awful, patently unscientific writing in this article.Thermodynamic (talk) 08:55, 19 December 2011 (UTC)
Serious, unscientific errors
This lovely gem is also contained in the article:
"Slopes flatter than 25 degrees or steeper than 60 degrees typically have a lower incidence of avalanche involvement, likewise slopes with windward and sunny exposure have a lower incidence of avalanche involvement."
The first part is fine, but the second part is in direct contravention to research performed by Grimsdottir that is cited by The Avalanche Handbook. The Avalanche Handbook states that when slope use is accounted for, aspect by itself is a poor predictor. Furthermore, I am unaware of any specific statistics on avalanche involvement on windward slopes. This should be removed or refashioned.Thermodynamic (talk) 08:54, 19 December 2011 (UTC)
Serious, unscientific errors
From the article:
"Snow that has been water saturated to the point of slush can accelerate on shallow angled terrain; while a cohesive snow pack will not accelerate on very steep slopes, such as the typical snow pack in the Chugach Mountains of Alaska."
A cohesive snow pack will not accelerate on very steep slopes???? This is just idiocy. Does the original author mean that a cohesive snowpack can stick to very steep slopes? There is a large difference between sticking to a steep slope and accelerating on a steep slope. Obviously, snow accelerates very well on steep slopes.
I wonder if this article has been neglected for so long because people felt the errors were simply too overwhelming to fix.
- In summary: Go for it. Just make sure there are verifiable sources in mind when making edits. Personal experience isn't enough. Will Beback talk 10:00, 19 December 2011 (UTC)
- Citing sources won't be a problem, and I hope you can see from my comments on the Discussion page ( which include citations ), that I'm not writing this content from "personal experience". First the misleading garbage should be removed, and I will cite sources in the comments when I make the edits. ( Or on the talk page, as I have done here. )Thermodynamic (talk) 10:11, 19 December 2011 (UTC)
This section does not even bother to discuss the #1 technique for avalanche avoidance: avoid steep slopes; do not travel on them; do not cross below them. This will have to be fixed.Thermodynamic (talk) 11:02, 19 December 2011 (UTC)
Classification and terminology
From the article as it stands:
"Slab avalanches are generated when an additional load causes a brittle failure of a slab that is bridging a weak snow layer"
This is wrong - or worse: it's just a bunch of gobbledygook. Brittle failure of a slab that is bridging a weak layer?????
The failure of the slab itself isn't why the avalanche forms.
1. The slab itself fails because gravity pulls the slab downhill. 2. Gravity is much more apt to pull a slab downhill after failure of some component of the interface between the slab and whatever is below the slab. 3. The failure of this interface is usually referred to as delamination.
Gosh, this section just has to be cleaned up.
Proceedings of ISSW 2010 http://www.avtrainingadmin.org/pubs/2010_ISSW_Proceedings.pdf
- Some insights into fracture propagation in weak snowpack layers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 716
- Fracture energy of weak snowpack layers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
ANTICRACKS: A NEW THEORY OF FRACTURE INITIATION AND FRACTURE PROPAGATION IN SNOW
Avalanches as critical phenomena
From the first sentence of the article:
"causes a critical escalating transition from the slow equilibrium evolution of the snowpack"
Research by McClung ( one of the world's leading avalanche researchers ) presents strong evidence that avalanches are non-critical punctuated equilibrium phenomena. Since the current version does not cite a source, I am going to make a correction and cite McClung's research.
I fixed a sentence that incorrectly described how avalanches form. There were really too many errors to even discuss, so I simplified the language and cited an impeccable source. The model of fracture propagation comes from this paper:
ANTICRACKS: A NEW THEORY OF FRACTURE INITIATION AND FRACTURE PROPAGATION IN SNOW http://www.issw2008.com/papers/P__8212.pdf
Very basic cleanup completed
I've finished the very basic cleanup. It's a lot better and I've removed a lot of errors ( but not all of them ).
Separating avalanche rescue topics
The avalanche rescue information needs to be moved to a separate article. Avalanches are natural phenomena, and the quantity of information biases the article toward human-avalanche interaction. This needs to be fixed. Thermodynamic (talk) 06:15, 20 December 2011 (UTC)
- That may be appropriate. See WP:SPLIT for general guidelines. When the new article is created it's important that the edit summary mentions that the original material came from this article. That's necessary to maintain the link to the creators of whatever text is copied.
- Regarding the rescue material, we can discuss rescue techniques, etc, but we should not structure it as a how-to guide. Will Beback talk 06:20, 20 December 2011 (UTC)
- Companion rescue contains a lot of "how to information" that will need restructuring or changing. Ack. Thermodynamic (talk) 09:04, 20 December 2011 (UTC)
Incorrect photo label
There's a new photograph labelled "Starting powder snow avalanche". This looks like a slab avalanche with a powder cloud. ( You can see fracture lines on the left side of the rear of the avalanche. ) This caption should be changed. A dry flowing avalanche is not the same as a powder avalanche.Thermodynamic (talk) 10:18, 22 April 2012 (UTC)
Three Part Description
There's a new, three-part description that is very poorly written and DOES NOT adhere to any of the standard geoscientific terminology related to the phenomena.
- The description of avalanche formation as a mechanical phenomenon does not even discuss avalanche formation from a mechanical perspective ( fracture mechanics, delamination, catastrophic failure ).
- Avalanches are not released by gunshots, unless you're talking about a howitzer.
- Part 3? "Third it is an event."??? Honestly, this is just noise.
The section on dynamics is more of summary of the state of current ongoing research, which begs the question of whether it is even appropriate in a wikipedia article? I mean this isn't supposed to be a literature review for GeoPhys, is it? Ideally this section should be removed, but failing that it should summarize established empirical observations of avalanche dynamics (not simulations and models, which are rightly continually revised and improved), and only point to wikipedia articles on the mathematical modelling of flows and turbulence. Why is there a section on mathematical models of the dynamics of fracturing and flow but no section on the evolution of snow packs? In particular a section on snow pack evolution should compare and contrast the two dominate processes: sintering/rounding versus faceting/dendrite growth.
Good lord, why on earth is there a major section dedicated to the rutschblock test? If there is going to be information on snow evaluation methods it should be on a separate page, with a brief introductory reference from the main avalanche page. There are many more tests and observation methods that also deserve discussing, such as the field tests: penetration resistance, compression failure, shovel shear, saw propagation, temperature observations, humidity observations, etc...; and then there are the laboratory tests which surely deserve mention somewhere?188.8.131.52 (talk) 20:18, 6 March 2013 (UTC)
I'm proposing a new structure for the avalanche page. I have outlined the structure in the sandbox page of the Avalanche_Sandbox account. Please feel free to edit User:Avalanche_Sandbox/sandbox, and comment in the talk page. Thank you Avalanche Sandbox (talk) 16:30, 7 March 2013 (UTC)