Avalanches kill back country recreationalists every year, including skiers, snowboarders, snowshoers, and snowmachiners. All back country users should have knowledge of the basic physics of avalanches to help them evaluate local and regional potential for slides. The foundation of this knowledge comes from understanding how the surrounding environmental conditions in previous weeks, previous days, and the day in question all contribute to snow stability or instability, and how specific factors affect snow on a micro-scale, which determines how snow slopes will behave on a macro-scale. There are two major types of avalanches (excluding debris avalanches from broken cornices and ice formations). These are point releases, or loose snow slides, and slab avalanches. While point releases can be dangerous and should be avoided, slab avalanches are much more catastrophic and account for most of the backcountry avalanche disasters involving humans. Basic physics of point releases are discussed here, followed by a discussion on the basic physics of slab avalanches, and how external factors contribute to the stability or instability of a snow covered slope.
BASIC PHYSICS OF POINT RELEASE AVALANCHES
Point release avalanches, or loose snow slides, begin at one point on a slope and get progressively wider as they proceed down the slope. A fundamental characteristic that must be present for this type of avalanche to occur is a surface layer of cohesionless, or nearly cohesionless, snow (University of Colorado IBS 1975; Fredston and Fesler 1994). An initially small amount of snow begins to move downward when the force of gravity is greater than the forces of cohesion at a particular angle or when debris from above starts the s...
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...ditional weight of one skier crossing at a time.
BIBLIOGRAPHY FOR "THE PHYSICS OF AVALANCHES"
Daffern, T. 1983. Avalanche safety for skiers and climbers. Alpenbooks, Seattle, WA.
Fredston, J.A., and D. Fesler. 1994. Snow sense: a guide to evaluating snow avalanche hazard. Alaska Mountain Safety Center, Anchorage, AK.
Graydon, D., and K. Hanson, editors. 1997. Mountaineering: the freedom of the hills, sixth edition. The Mountaineers,
Seattle, WA.
Perla, R.I., and M. Martinelli. 1976. Avalanche handbook. U.S. Department of Agriculture, Agriculture Handbook 489.
University of Colorado IBS (Institute of Behavioral Science). 1975. Snow avalanche hazard in the United States: a research assessment. Assessment of Research on Natural Hazards, Program on Technology, Environment, and Man, Monograph NSF-RA-E-75-017.
Cross-country skiing is as much of a competitive sport, as it is a back country one. Cross-country skiing is enjoyed by people of all ages, and can be relatively inexpensive. There is no need for lift tickets and with a little maintenance equipment can last for decades. As a result of its broad audience, many people don't realize that physics plays a large role in cross-country skiing. This web page was designed to briefly describe some of the concepts behind the physics of skiing, and give a basic understanding of both the sport and the science.
Climbing makes for a difficult expedition, you need to give up the wrappers when you was ascending. You need to give up the heavy things, you need to give up your wrappers, and you need to give yourselves. Sometimes we need to give up our lives to climb the mount Everest. According to snow storm, the energy, the oxygen and the people who desired prove themselves the spring’s 96s expedition to mountain Everest was destined to be the most tragic.
States on the lee, or down wind, sides of the great lakes receive lake-effect snow every year. For some cities this can push the average snowfall up to 400 inches. During the February storm of this year records were broken for the most snowfall in one storm. For a duration of the storm snow was falling at a rate of six inches or more per hour. Some of the images captured from the event leave some in disbelief that such a thing could even happen. Storms of this magnitude completely shut down all activity. Many areas do not have equipment capable of handling such mass amounts of snow, and even if they do the task is overwhelming. (weather.com 2006)
Typically impacting a small area, one location could see in excess of a foot of snow where a few miles away, could be only seeing flurries. LES (Lake Effect Snow) can come quickly and produce conditions that are very hazardous for traveling. Things like this as well as other impacts are important to note and as forecasters, try to inform the public to be prepared for an event like this. To understand the whole idea of lake effect snow, one must travel to the past where this phenomenon was first discovered and from there; move forward in time to see the progress that has been made not only in understanding this, but also forecasting it as well.
January 12, 1888, a blizzard covered the northwest part of North America that claimed many lives. This blizzard was considered to be the worst blizzard of all time, and was dubbed the “the Schoolchildren’s Blizzard”, for claiming the lives of so many school children on their way home. The death toll of this murderous blizzard rose, because of lack of preparation and being uninformed. During this time, many farmers and families were unprepared to survive a blizzard of this magnitude, by the lack of clothing they wore. Forecasters were not as accurate enough to inform people on the weather conditions. Also, shelter was a major factor in protecting themselves from the winter storms, but the shelter was not stable
Often, the effects of Mountain top Removal are disastrous, the wildlife habitat is damaged and vegetation loss usually leads to numerous floods and landslides. When explosives are used, fly rock, ...
(6) The suddenness of the winter storm caught people by surprise. A roar “like an approaching train” was all the warning the storm gave. (130) The roaring wind and snow brought darkness and dropping temperatures. The people who were inside when the blizzard struck faced a dilemma. Staying inside and doing nothing seemed “heartless,” but going into the storm “on a rescue mission was likely to be fatal to the rescuer and useless to the lost.” (143) The people who were unfortunate enough to be away from home, whether they were at school or working with their livestock, had to make a difficult decision. They could either risk trying to make it home or chance it out and stay where they were. Schoolteachers had to decide whether to send the children home or keep them at the school. If anyone ventured outside, he or she risked frostbite, hypothermia, and likely
Have you ever wanted to prove to everyone that you are a hard worker that is willing to give up everything to go on an adventure? If this is you than Everest is the perfect place for you. A great deal of Everest’s dangers are expressed in his book which should either inspire you to try this journey or sway you away from the treacherous mountain. In the story, “ Into Thin Air,” by Jon Krakauer a true story is told of a dangerous voyage up and down Everest. The climb up was arduous and long according to Jon, but the climbers sacrificed everything to get to the top, which most of the climbers achieved. However, emotions shifted when a storm swooped in and killed many of the climbers that were stuck on the summit, around 12-19 in total. The devices
“At 12:42 p.m. the air was perfectly calm for about one minute; the next minute the sky was completely overcast by heavy black clouds which, for a few minutes previous, had hung along the western and northwestern horizon, and the wind veered to the west and blew with such violence as to render the position of the observer on the roof unsafe. The air was immediately filled with snow as fine as sifted flour” (Potter). No one expected the blizzard that would soon come rolling over to create some of the unfortunate deaths. Now, the questions are what exactly happened during the storm, how are snowstorms created, and what damages it caused.
Cascading down frozen mountain, crystallized flakes of chilling water gracing my face with it’s presence; free falling sixty feet, only to be saved by a pillow of snow: this is why I snowboard. The pure rush of adrenaline from the sport has turned what started as a backyard hobby into an Olympic event. Though you may think snowboarding is just a board strapped to your feet; the engineering and history of it have a much richer back story.
With steeper slopes comes more experienced riders, which also comes higher speeds. When zooming down a steep slope momentum carries snowboarders. If a snowboarder loses speed their balance follows suit. Consequently, we may look reckless but, we have complete control. From a bystander’s view at the base of the mountain it looks like we are going left and right with no sense of direction with poofs of snow every time we change direction. In reality, when we change direction, the momentum shift slows us down and keeps us in control. While it looks like we are going to zoom off and hit the nearby tree, we change our course to restrict the speed of our
To begin with, the landing of the snow on the road caused many damages to them. This was because the levels on which the roads were raised were in different proportions. This, therefore, prevented lack of flow to be experienced on the roads. Moreover, the cracks that were observed on the roads came about because of the difference in the temperatures of the country.
In the movie Touching the Void, it starts off by two people named Joe Simpson and Simon Yates that go to Peru to climb the Siula Grande Mountains. The ranges of those mountains haven’t been climbed and those who have tried to climb them, failed. Simpson and Yates tried to climb the glacier even though they knew the risks. A glacier is made up of fallen snow that has been accumulated throughout the years and it forms into a large and thick ice masses. It’s where the snow remains that have been remained in a certain are for long periods of time and it transforms into ice. The type of glacier that they climbed was a confined glacier. The glacier was a depositional, because when Simpson was walking towards the campsite where Yates was, he had to pass through the moraines, where it’s a formed accumulation of glacial debris in which consist of soil and rocks.
I have been skiing for about five years and I find it to be one of the most fun and challenging sports there is. A lot of the reason it is so challenging is because of the laws of physics such as gravity and friction. In this essay I will discuss how physics relates to skiing and how this physics makes skiing so fun and challenging. I will also discuss how things like wax and the shape and width of your skis can affect these laws of physics and enhance your skiing.
The year was 1992; a cold December arctic wind had brought a chance of snow to the area. It was the weekend and time to relax after a long hard week at work. The weather service had predicted several inches of snow to blanket the region by the next day. Not to worry: it was the weekend and traveling was not a necessity.