Talk:Avalanche

message: 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)
thread_title:  Prediction 

message: 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. — Preceding unsigned comment added by 200.67.133.215 (talk) 20:45, 5 December 2005 (UTC)
thread_title:  Slab vs. point-release 

message: Maybe some basic stuff about snow-crystal structure and formation, and maybe how this relates to snowpack stability? — Preceding unsigned comment added by Daveohyeah (talk • contribs) 21:43, 5 December 2005 (UTC)
thread_title:  Snow-crystal structure 

message: 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)
thread_title:  Debris avalanches 

message: 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 — Preceding unsigned comment added by 136.159.162.39 (talk) 17:22, 8 May 2006 (UTC)
replies: text: 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)
thread_title:  The Group 

message: 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.
SnapJag 03:31, 9 August 2006 (UTC)
thread_title:  Large portion removed has been put back 

message: Can someone tell me if you can start an avalanche by yelling? It happens all the time in cartoons but Iwasn't so sure.--4.160.237.223 02:21, 15 November 2006 (UTC)
replies: text: 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)
replies: text: Vibrations actually cause the most Avalanches.  —Preceding unsigned comment added by 98.15.155.118 (talk) 17:32, 7 April 2008 (UTC)
replies: text: What do you think sound is? Vibrations! Tomalak Geret'kal (talk) 09:12, 14 October 2009 (UTC)
replies: text: Not enough vibrations though  InfernaIBaze (talk) 01:23, 26 November 2022 (UTC)
replies: text: edit: not strong enough of a vibration  InfernaIBaze (talk) 01:24, 26 November 2022 (UTC)
thread_title:  Yelling 

message: How do people die in avalanches do they suffucate or die of the cold? DPM 22:24, 12 December 2006 (UTC)
replies: text: 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)
thread_title: Death

message: 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. — Preceding unsigned comment added by Jossy89 (talk • contribs) 11:56, 2 January 2007 (UTC)
thread_title: Additional Picture

message: 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)
replies: text: 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)
thread_title: "Gravity Current" removal

message: At least needs a citation. I have not seen any documentation of this concern. DriveBy27 01:07, 29 January 2007 (UTC)
thread_title: "Mobile phone interference with transceiver?"

message: i read a book where a 14 year old lived for a week before almost dying. is that possible?
jamie 72.93.88.4 00:34, 30 January 2007 (UTC)
replies: text: 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)
thread_title: Avalanche survival

message: 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)
thread_title:  So Helpful!!!!! 

message: 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?
The world may never know... —The preceding unsigned comment was added by 68.43.89.134 (talk) 13:48, 3 February 2007 (UTC)
thread_title:  That is awesome 

message: 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)
thread_title:  Recent Edits 

message: 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)
thread_title:  GPS 

message: 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)
replies: text: 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)
thread_title:  Picture of slab avalanche 

message: 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. — Preceding unsigned comment added by Herwijn (talk • contribs) 20:16, 4 March 2008 (UTC)
replies: text: Wikipedia is not a manual, guidebook, or textbook. -shogun (talk) 20:41, 7 April 2008 (UTC)

text: 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)
replies: text: The existing probe section appears appropriate. I've never heard of anyone using a probe during an avalanche, and I doubt it would do anything to reduce the danger. ;)  ·:· Will Beback  ·:· 22:26, 14 November 2008 (UTC)
thread_title: How to

message: 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! 114.77.205.138 (talk) 07:19, 27 December 2008 (UTC)
thread_title: Southern Hemisphere has avalanches too!

message: 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 • contribs) 04:06, 11 February 2009 (UTC)
thread_title:  Changes 

message: can someone create a new article for Avalung?  —Preceding unsigned comment added by 93.173.11.174 (talk) 20:02, 30 October 2009 (UTC)
thread_title:  Avalung 

message: 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".  — Preceding unsigned comment added by 131.191.34.72 (talk) 06:48, 19 December 2011 (UTC)
thread_title:  Incorrect Caption 

message: "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.
Am I allowed to make corrections? I can provide credentials.  — Preceding unsigned comment added by 131.191.34.72 (talk) 07:19, 19 December 2011 (UTC)
replies: text: 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)
replies: text: Thanks. — Preceding unsigned comment added by Thermodynamic (talk • contribs) 08:30, 19 December 2011 (UTC)
thread_title:  Other Errors 

message: "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)
thread_title:  Unscientific! 

message: 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
Either type of avalanche may involve wet or dry snow. Can I clean this section up?  — Preceding unsigned comment added by Thermodynamic (talk • contribs) 08:30, 19 December 2011 (UTC)
thread_title:  Major strangeness 

message: 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)
thread_title:  Serious, unscientific errors 

message: 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.
Thermodynamic (talk) 09:32, 19 December 2011 (UTC)
replies: text: 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)
replies: text:  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)
thread_title:  Serious, unscientific errors 

message: 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)
thread_title:  Avalanche avoidance 

message: 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. 
# The slab itself fails because gravity pulls the slab downhill.
# 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.
# The failure of this interface is usually referred to as delamination.
Gosh, this section just has to be cleaned up.
Sources: 
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 
http://www.issw2008.com/papers/P__8212.pdf
Thermodynamic (talk) 11:11, 19 December 2011 (UTC)
thread_title:  Classification and terminology 

message: 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.
Thermodynamic (talk) 01:56, 20 December 2011 (UTC)
thread_title:  Avalanches as critical phenomena 

message: 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
The authors are all considered leading experts in the field.  — Preceding unsigned comment added by Thermodynamic (talk • contribs) 02:24, 20 December 2011 (UTC)
thread_title:  Failure modes 

message: 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 ).
Thermodynamic (talk) 05:11, 20 December 2011 (UTC)
thread_title:  Very basic cleanup completed 

message: 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)
thread_title:  Incorrect photo label 

message: 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.
Does anyone care if I revert to the previous description - it was much better.Thermodynamic (talk) 19:40, 16 November 2012 (UTC)
thread_title:  Three Part Description 

message: 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.
Compared to the article on tornadoes the avalanche article needs major improvement. — Preceding unsigned comment added by 198.161.2.241 (talk) 20:01, 6 March 2013 (UTC)
thread_title:  Dynamics 

message: 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?198.161.2.241 (talk) 20:18, 6 March 2013 (UTC)
thread_title:  Rutschblock 

message: 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)
thread_title:  Page restructuring 

message: I would like to propose firstly that we rename the page to "Snow Avalanches" this deals with the confusion of "Rock Avalanches" and other mass movements which should each have their own page. The it would be better to split the page so that "Notable Snow Avalanche Accidents" is a  separate page. This could easily be rather large.
Similarly Everything to do with Avalanche safety would best be put on a different page. The use of beacons. safe travel and so one are separate from the physical phenomena
There is also a little too much of people with partial knowledge getting things wrong. I see lots of categorical statements about slabs and powder clouds for example and they are misinformed. The situation is complicated and a lot of it is in error. I am professor who's main research topic is snow avalanches, and I've worked in this area for twenty years. Jim McElwaine (talk) — Preceding undated comment added 00:24, 27 July 2017 (UTC)
thread_title: Reorganisation