Photograph by Ryland Loos BASIC AVALANCHE AWARENESS This brochure is designed to let the - PDF document

Photograph by: Ryland Loosuser know that avalanche danger does exist inNew York and gives basic ideas of what to look forand avoid. To learn more about avalancheawareness consider courses, reading and experience.1.Know basic avalanche rescue techniques.2.Check the snow depth.3.Check how much new snow has fallen.4.Practice safe route finding.5.Check the degree of the slope.6.Check the terrain.7.Carry basic avalanche rescue equipment.8.Never travel alone.9.Let someone know where you are going.10.Do not be afraid to turn around. 11.Use common sense. Organizations www.fsavalanche.org Westwide Avalanche Networkwww.avalanche.org alanche.org/~aaap Books Published by The Mountaineer BooksSnow Sense: A Guide to Evaluating Snow Avalanche HazardPublished by Alaska Mountain Safety Center, Inc.www.dec.ny.gov Photograph by: Ryland LoosAvalanchePreparedness in theAdirondacks New York State Department ofEnvironmental Conservation An avalanche is a mass of snow sliding down amountainside. Avalanches are also calledsnowslides; there is no difference in these terms.An avalanche occurs when the stress (from gravity)trying to pull the snow downhill exceeds thestrength (from bonds between snow grains) of thesnow cover. Four conditions must be present foran avalanche to occur."a steep slope "a snow cover a weak layer in the snow cover The avalanche danger increases with majorsnowstorms and periods of thaw. About 2,000avalanches are reported to the U.S. Forest ServiceAvalanche Center in an average winter. More than80 percent of these occur during or just after largesnowstorms. The most avalanche-prone monthsare, in order, February, March, and January.Avalanches caused by thaw occur most often inAbout 90 percent of all avalanches start on slopesof 30-45 degrees; about 98 percent of allavalanches occur on slopes of 25-50 degrees.Avalanches release most often on slopes abovetimberline that face away from prevailing winds.This is because leeward slopes collect snowblowing from the windward sides of ridges.Avalanches can occur, however, on small slopeswell below timberline, such as gullies, road cutsand small openings in the trees. Very dense treescan anchor the snow to steep slopes and preventavalanches from starting, however, avalanchescan release and travel through a moderately denseforest. Most avalanches occur in the backcountry,outside of developed ski areas. You can reliably avoid avalanches by recognizingand avoiding avalanche terrain. Travel on thevalley floor away from large avalanche runouts,along ridgetops above avalanche paths, in densetimber, or on slopes of 25 degrees or less that donot have steeper slopes above them. AvoidYou cannot entirely eliminate risk if you travel inavalanche terrain, but you can minimize risk byusing good technique: climb, descend, or crossavalanche areas one at a time; cross a slope at thevery top or bottom if possible; climb or descendthe edge of a slope rather than the center; carryand know how to use avalanche rescue gear; andturn back or alter your route if you detect signs ofunstable snow.When the snow cover is very unstable, nature oftenbroadcasts clear danger signals. Fresh avalanchesare the best clue. Snow that cracks, collapses, ormakes hollow sounds is also unstable. Weak layersthat are found by digging snow pits are signs ofunstable snow. Snow that has become wet fromthaw or rain can be dangerous.Even if you find no signs of unstable snow, youshould always travel observing the techniqueslisted above to minimize risk.You should always have an avalanche transceiver(or beacon), shovel, and a collapsible or ski-polece frequently to beYou should not take extra risk just because youhave rescue equipment. Always carry a day packwith enough equipment to spend the night.Surviving avalanches can depend on luck, but it isalways better to avoid them in the first place.Remember that only 1 of 3 victims buried without abeacon survives. If you are caught, first try toescape to the side, or grab a tree or rock. If you areknocked down, get rid of your poles, skis, and aheavy pack. Swim with the avalanche to try to stayon top and avoid trees. When the avalanche slowsdown, reach the surface or make an airpocket.Never put everyone on the slope. Only oneHave an escape route planned. Always thinkavalanche. What will you do if the slope slides.Have a plan before you travel.Use slope cuts. Keep your speed up and cutacross the starting zone, so that if the slopeslides, your momentum can carry you off themoving slab into safer terrain. You can do thison skis, snowboards or on snowmobiles. Watch out for cornices. They always breakfarther back than you think. Always give them awide berth. NEVER, NEVER walk out to theedge of a drop-off without first checking it out.Many people have died this way. If it looks too dangerous, find a safer route. Useterrain to your advantage. Follow ridges, thicktrees and slopes with safer consequences. Youcan almost always go back the way you came.The route got you there, it will most likely getyou back as well. If there's no other choice, go underground. Youcan almost always weather out a bad storm orbad avalanche by digging a snow cave orseeking the shelter of a crevasse. You may beuncomfortable but you will be alive.