January 7, 2008

The "Extended Column Test"

The promotion of this "test" as something useful in decision making in the field has bothered me for quite a while. I will have to find time to write more about it again later, but here is the short version of my concerns, as well as a suggestion for what to ask anyone promoting this.

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April 13, 2007

Slabs Vs Loose Snow

Slabs of snow are continuous bodies, and are subject to deformation and the development of internal stresses for that reason. Loose snow without any cohesion does not form a continuous body and its behavior is that of a collection of unconnected grains. Comments in at least one public advisory show a lack of understanding of the fundamental differences.

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February 27, 2007

The "Critical Temperature Gradient" Myth

For years the figure of 1 C per 10 cm of depth has been called a "critical temperature gradient" and considered the gradient in the snowpack at which faceting of the grains begins. In a recent forum topic the original question was what is most important for facetting and of course this number was presented right away.

What is actually important is the vapor pressure gradient. Depending on the temperature the gradient may need to be much larger than this "critical value" before faceting actually begins to occur.

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January 26, 2007

Alpha (Runout) Angles and Climate Regimes

The alpha angle is the angle from the end of the runout to the top of the starting zone. For a brief definition including a diagram you can see the avalanche center glossary:

Avalanche Center -> Education Center -> Glossary -> Alpha Angle

Alpha angles (used to measure runout distance) do NOT depend on climatology. Whether a mountain range is maritime or continental (or something else) does not make much difference in alpha angles. Despite what may have found its way into the popular literature. What is important isn't clear, but it's not climate. Every mountain range seems to offer its own behavior regarding maximum runout potentials, and each range must be analyzed separately.

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August 5, 2006

Book Review - "Secrets of the Snow"

Summer is the time when I can try to read a few things, avalanche related and not. I usually purchase various new and archival publications to add to the library. Among my recent purchases is "Secrets of the Snow - Visual Clues to Avalanche and Ski Conditions" by Ed LaChapelle.

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July 26, 2006

Avalanche Bills HR 2039 and SR 225

Comments on HR 2039 and SR 225 (Text of Bill)

These two identical bills would provide for federal funding in the areas of avalanche control and safety. Senator Stevens (R-AK) has introduced SR 225 in the last congress as well as early in this congress, and given that it repeatedly stalled Rep. Young (R-AK) introduced an identical bill in the house early in this congress. The original bill would have appropriated $15 million per year for 5 years. After sitting in the House Resources Committee for over a year Rep. Young asked the proponents of the bill to redraft a new proposal at a more realistic level. The current draft requests a total of over $14 million spread over 5 years.

The basic areas for which funds would be allocated are artillery refurbishment, management and the development of alternatives to artillery, mass disaster prevention, education of high-risk groups, and data management.

An overview of my thoughts and opinions on each of these areas is presented here. I do not support this bill. I feel there may be some need for artillery management, but I also believe that policy barriers are discouraging the use of alternatives. Any bill of this nature should require, or be contingent upon, changes to current agency policies. I also believe existing programs could be used more effectively to promote new alternatives.
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May 8, 2006

Earn a "Level 1 Certificate" in just one day

Looking for a Level 1 class near Portland?

Here we go again. First it was an annual one-day class in the Adirondacks and now it’s the Mazamas in Portland, Oregon. Both offer a "Level 1 Certificate" through a one-day class. I’m sure there are others as well. Never mind that the established guidelines published by the American Avalanche Association are clearly based on a 24-hour class. While such a "certificate" should be recognized as a standard of sorts (after all, it’s a guideline and not a curriculum with any assessment) its become a bit of a joke now that anyone can spend a few bucks and one day and obtain one.

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April 20, 2006

Welcome / About this Blog

Welcome to my blog on snow avalanches. Over time I've found various issues, comments and claims that I'd like to comment on. This blog will allow me to do that. The comment feature allows a certain amount of feedback, pro and con. More extensive discussion is always welcome in the forums at http://www.avalanche-center.org/phpBB2/

Titles of the most recent posts can also be found on the newsfeeds page at http://www.avalanche-center.org/News/newsfeeds/

While I encourage the use of avalanche-center.org for discussions (as well as for general reference and education) this blog has no formal or official affiliation with that site. Nor any other. Nor is it affiliated with any other individual(s). Everything written here is by me, and I'm responsible for it, unless it is a comment or otherwise attributed to somebody else in particular.

Comments need to be approved, otherwise there is an overwhelming amount of spam. I generally don't believe in approval or editing based on content so disagreements and opposing points of view are welcome as long as they are civil and intelligent. So if you don't see your comment for a little while it's just a matter of me approving it.

I'm also open to guest and invited blog entries, feel free to request a topic or a person to invite by emailing me at snowman@csac.org