Educational Resources
| Preparing for an Avalanche Course |
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Welcome to the Level 1 Pre-Course Study. Familiarize yourself with these concepts so you can come to your course and build on your existing skills. By reading through this, you can perhaps answer some questions that you currently have as well as develop questions that you can have your instructor explain, either in the classroom or out in the field. For some of you, this may be where your avalanche education begins. For those of you who have taken an avalanche course in the past, or for those who are simply interested in staying informed, these steps will help make you 'avalanche aware' this winter. PLANOBTAIN A LOCAL AVALANCHE BULLETIN
These are available for your region by clicking on this link: www.avalanche.org a map will display links to all the avalanche centers throughout North America. Additionally, there are many good avalanche related links on this page.
Planning and preparing for a trip must be done well before your outing. This particular step is often overlooked, but it is critical for your safety, and that of your group. First, attempt to ascertain if you will be traveling in avalanche terrain. You can determine this by looking at maps, guidebooks, and by speaking with locals at sports stores, Forest Service and National Park personnel, and ski patrollers. Assuming you will be in avalanche terrain, you already know about telephoning, or looking on the web, for the local avalanche forecast. Obtain this information on the morning of the first day of your scheduled trip; however, access it prior to the trip so you can begin to identify some general trends. Begin thinking about when you should plan on leaving for the trail head and how long you'll be gone. Think about a turnaround time that gives you plenty of opportunity to return in daylight. Consider what group equipment must be brought and who will carry it -- basic first aid equipment, cell phone, headlamps and radios if deemed necessary. Will this be a short trip with friends in familiar terrain or a multiple day outing with people you don't know? What are the goals and objectives? What's the weather forecast? Topics such as creating options and group profiling will be covered below, however think of yourself as a pilot gathering pre-flight information for a cross country flight.
CREATE OPTIONSAs you plan and prepare, consider three trip variations: your Ideal Trip, which may take you through avalanche terrain; a Preferred route, which minimizes your exposure to avalanche terrain; an Alternate route and an Easy Exit/Evacuation option. Additionally you can discuss alternates such as going to ski area where avalanches are controlled or going bowling -- something completely safe, should the conditions change dramatically. As well, people often assume that summer trails are safe in the winter. Not so! Remember that snow in avalanche terrain can slide if unstable conditions exist. Frequently, conditions may change overnight, such as a storm blowing in or some weather event that makes your original 'Preferred' route through avalanche terrain unacceptable. Because you have created options you can now consider the safer alternatives instead of feeling committed to reaching the objective of your trip. This commitment factor often puts people in danger. Many accidents can be attributed to groups who had 'summit fever' and no alternatives in place on which the group could act. Consequently, when things started to get dicey, instead of aborting or changing their route, they stuck to their prior commitment and got into trouble. They had not created options. It's human nature to set an objectively and achieve it, sometimes at all costs; however in the mountains in avalanche terrain the cost could be your life. Don't let it happen to you! Remember your goal is to return safely. The objective needs to be acceptable and reachable by everyone in the group. Additionally you need to have options in place that everyone has agreed to so you don't get caught up in 'summit fever!'
EQUIPMENTFor any backcountry trip, consider what the minimum required safety equipment is: an avalanche beacon, shovel and probe. As well, pack the usual components of the Ten Essentials: food, water, extra warm clothes, cell phone, emergency overnight equipment such as a bivy sack and a way to start a fire, and other items you might typically carry (you can split up group gear to be carried among the group). The beacon, probe and shovel are always taken into the backcountry, and the beacon is always turned on at the trail head, and off when back to the car. It's not appropriate to save batteries with reasoning like, "We'll turn it on when we get into avalanche terrain." Turn it on and check each party member's ability to transmit and receive as you head out from the trail head. Should someone in the party get caught and buried, you will need to know how to use the beacon to locate the victim, the probe to pinpoint their exact location, and shovel to dig them out. A transmitting beacon is worn by all members of the party traveling through avalanche terrain. If you're one of the lucky 2/3 of avalanche victims who do not die from initial trauma sustained in the ride down the side of the mountain at speeds up to 80 mph or more, it will be up to your party to locate and dig you out before you asphyxiate. The transmitting beacon will electronically transmit your location to people on the surface searching for you with their beacons in the receive position. Working with and understanding how your beacon functions is not something that your figure out in an actual rescue situation. A successful rescue will depend upon your proficiency with a beacon. If you have not practiced prior to going out, plan on the rescue not going so well and your wife, boyfriend, husband, friend, brother or sister dying as you figure out how to use this thing. If on the other hand, you have practiced and practiced and practiced, the member of your party buried stands a chance of getting extracted in a timely fashion. Do not even discuss the pros and cons of purchasing and wearing a beacon. Many excellent beacons are available for around $300.00. Now that you've purchased your rescue equipment, it's critical to practice with it, especially the rescue beacon You need two beacons for practice purposes. Ideally you will practice in snow, but if you don't have snow where you are, you can begin to get a clue how things work by having someone hide one beacon while it's transmitting and then go looking for it with the other beacon set to receive a transmitted signal. Have the hiding person get creative: hide it in the closet, under the mattress, wherever - stump each other! Eventually you must practice in snow, initially burying the beacon a foot deep, eventually three feet or deeper - this is the average burial depth of victims buried in an avalanche. Don't forget to set the buried beacon at differing orientations; rarely is a beacon found exactly horizontally or vertically. Creating scenarios where you recreate an avalanche accident is the best way to 'practice'. Stomp out a good sized area in the snow and with your back turned, have your partners hide a transmitting beacon, preferably on a hillside, then see how fast you can locate the buried beacon. Mix it up: make it difficult because there's a good chance that it won't be as easy should you be involved in a real rescue. Trade places and hide a beacon for your friends. Have them work as a team and see the problems that arise. Time it and see how long it takes. Eventually bury two beacons and see what's required to locate the pretend victims. Most people will not practice. You must force yourself to get out there and do it! You have to understand the problems that can arise during a rescue and be able to react. You can only expose yourself to this through practice. Most multi-day avalanche courses have rescue scenarios as part of the curriculum. Practice with beacon, shovel, and probe or don't go into avalanche terrain. Note that at this point, everything that you have done up until now has been done at home (other than the beacon field practice). The avalanche bulletin was obtained either by phone or via the web, your Planning on your route done via maps, guide books and/or knowledge obtained from local authorities, shops and libraries or, on the web, was done at home. Options were determined at home through the Planning phase and discussed with party members either face to face or on the phone prior to the trip. The goals and objectives were discusses as well. Who's Coming On The Trip was as well easily ascertained and scrutinized at home. So much can be done in the safety of your home to reduce your risk prior to potentially exposing yourself to avalanche danger. Many accidents can be avoided by simply going through the processes described above. Begin thinking 'avalanche' from the beginning and there's a good chance you won't be caught. After all the above steps have been completed and you've ascertained that it's potentially safe to consider one of your options you can head for the trail head. TEAMWORK - who is coming on the trip?This is the part that can make or break your trip, with or without dangerous avalanche conditions. Who's coming, and can you trust your life to them? You may think, 'We're just going on a little snow shoe trip with some friends, what can go wrong?' A lot can go wrong! Many people have died in the backcountry on seemingly innocent outings on snowshoes, cross country skis and snowmobiles. There are volumes of books dedicated to avalanche accident case studies, documenting what went wrong. One such publication is The Snowy Torrents (http://www.csac.org/store/books-torrents4.html).
Here are some questions to ask about the people with whom you'll be heading out:
It cannot be stressed enough that this 'Teamwork' component will more than likely determine the safety and consequent outcome of your trip. Putting together a cohesive group that understands and has similar fitness levels, travel skills and expectations is imperative. If you want to take out your mom for a nice snowshoe or cross country ski or snowmobile ride in some gentle terrain, it's probably best to not invite your snowboarding friend who only wants to find a cornice, build a kicker and huck! Think hard about the makeup of the group, as your life may very well depend on it. As well, consider the size of the group: the larger the group, the more things to go wrong. Unless you are going on a paid-for, guided excursion where the guide is responsible for all of the decisions, consider creating a team approach, where all the members of the party are responsible for the safety of one another. Consider everyone's concerns and observations. It's up to each individual to monitor and challenge group decisions as well as share observations. If you have concerns, observations or suggestions, it is incumbent on you to speak up! Do not be led into danger by someone who thinks they are an expert -- the avalanche does not know they are an expert! The avalanche does not know that you have a dinner date for which you'll be late for if you don't take the most direct route. The avalanche does not know your kids are in day care waiting for you to pick them up. All the avalanche knows is that when the weight of the individual or group exceeds the strength of its bonds, it fails and slides!
OBSERVE - Look for cluesUsing 'common' and 'uncommon' sense to help you sleuth out the day's avalanche danger is a big part of the fun of being avalanche aware. This is where you become a detective. Let's start with the 'common sense' part of being a detective. Most of the relevant and easiest to gather clues to avalanche danger are provided by Mother Nature. We look for clues in the following categories: avalanches observed, weather and snow pack. We especially look for what we call 'Red Flags'. Red flags are clues that indicate the avalanche danger is present or rising. Case histories have shown that frequently red flag clues were present and observed by people caught and killed in avalanches. They didn't know that what they were observing were red flag. Do not ignore Mother Nature shouting out clues! [Note for snowmobilers: because snowmobiles are able to cover so much ground so quickly, it's important from time to time to stop your machine, take your helmet off and walk around. With the noise and speed associated with traveling on your sled, you need to stop from time to time and investigate. Often, walking around will produce collapses (whoomping) or shooting cracks in the snow pack that you may not have been aware of with your helmet on traveling at speed. Both collapse and shooting cracks are signs of instability.]
One of the most easily observable and most relevant red flags available to us is recent or current avalanches. Say you're driving to the trail head (and being the good detective that you are, always looking for clues) and you notice an avalanche. Try to determine how recent it was - the more recent, the more likely it is that instabilities still exist within the snow pack. Suppose you're heading out you actually see an avalanche happen, or you hear from someone else in the parking lot that saw one happen? How big was it - big enough to bury or injure you? Where did it happen? What triggered it? Did it occur naturally? Was it triggered by a human? If avalanches are running naturally, or look like they've run recently, and are being triggered by humans, this is one of the brightest red, red flag clues that Mother Nature can provide you. This is the one clue that is telling you loud and clear to reconsider your plan and consider your safer or more likely, your safest option now! In addition to nature's warnings, there are also weather red flags. One relevant red flag is lots of new snow, on the order of an inch per hour or more, coupled with winds that are moving snow. This combination can potentially stress the snow pack close to its breaking point. You or someone in your party could be the proverbial straw that comes along and breaks the camels back, so to speak. It's safe to say that during and immediately after storms that the avalanche danger is often at its highest. The snow pack has not had time yet to adjust to the new load. Give it time before rushing out and hitting the steepest slopes around. Rain and/or warm temperatures (32ºF. and above) can weaken the bonds in the snow pack as well. Intense solar radiation on sunny days can heat up the snow pack on sun-ward exposures, weakening bonds as the day goes on. All these weather related red flags can contribute to slope instability. Lastly, there are snow pack red flags. The snow pack is the snow lying on the ground. It comes down as individual snow flakes over the course of the winter and the different storms form different layers. Sometimes those layers bond well and sometimes they don't. Simply put, it's these layers with their different strengths and weaknesses that create avalanches. We can obtain clues about the snow pack as we travel over it, seeing shooting cracks or hearing loud whoomphs resulting from our weight on the snow, causing the collapse of weak layers below us. Seeing and hearing shooting cracks and whoomphs are red flags that are telling us that there are possible instabilities within the snow pack, and that it could potentially slide. As you go along during the day, constantly look for clues, constantly updating your own personal avalanche danger evaluation. You may have obtained the danger rating from the forecast center, but you need to do some evaluating on your own as you go along. There is no clear number of red flags that need to be present, but obviously the more red flags that pop up the more you need to err on the side of caution, exercising common sense and considering your options at all times.
CHOOSE TERRAIN - Identify Options and Evalauate Consequences
Will you be traveling in avalanche terrain? Avalanches most often occur on slopes of 30º - 45º or more but can start on slopes as shallow as 25º and as steep as 50º. In higly unstable conditions snow can slide under 20º. You must be able to identify when you'll be in avalanche terrain. You can learn how to measure the slope angle with an inexpensive slope meter available at most sporting goods stores. If you wish to eliminate your risk all together, plan your trip so it never intersects with slopes of more than 25º. However, just because you are in the middle of a valley on virtually flat terrain does not eliminate your risk if slopes above you are 30º or more and contain an unstable snow pack. Avalanches can be triggered from below and can run great distances. Be aware of this danger when you are down on the valley floor - look for signs of instability from Mother Nature and put distance between yourself and the slopes above. Classic avalanche paths are readily identifiable as big swaths cutting down through the trees. Often paths can be identified as having broken or damaged trees and vegetation. As you travel above tree line however, the paths become less defined and harder to identify. It's often smaller, undefined avalanche paths both above and below tree line that catch people. It is often reasonable and appropriate to travel in avalanche terrain. When we do so, however, it is wise to always look for the best routes to travel and the terrain where, if something should happen, you have the best chance of survival. Be aware of terrain traps like gullies and road cuts where if the snow slides it can pile up deeply on top of you. Leeward slopes, where the wind had deposited snow while often times offering the softest and deepest powder, may also be suspect, particularly right after a storm. The fact is that avalanche terrain is easy to identify, particularly if you buy and learn how to use a slope meter. By recognizing avalanche terrain, you can avoid it as the danger dictates.
TRAVEL WISELY - Manage the group and use travel techniques to reduce risk
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