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    Avalanche

    An avalanche occurs when a mass of snow

    falls down a mountainside. That is becausenew snow (which is not wet) accumulates on a

    more heavy snow layer. Since the new snowlayer is not compact, it could slide down

    toward the base of the mountain.Avalanches could be triggered by loud noise

    (yells, firearm shots, etc.). Skiers,snowboarders and climbers could also cause

    an avalanche.

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    There are two ways to reduce avalanche risks: byinstalling snowsheds or by triggering controlledavalanches. These protection fences are made ofrocks, soil and other materials. They preventavalanches to fill trails used by humans.

    Controlled avalanches cause the accumulated snowto fall down before it could trigger avalanches byitself. When nobody is in danger, explosives areused to produce a loud noise that causes anavalanche.

    Avalanches could be seen every winter inmountainous regions of Qubec. Fortunately, theydo not often occur near inhabited areas

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    What to Do During an Avalanche

    During the winter, do not venture in the mountainwithout an adult.

    If you walk in a trail after a snow fall, do not walkin the middle of it, but rather on the side.Avalanches always fall down in the middle of thepath; thus, if you are on the side, the risks ofbeing hit by the avalanche are lower.

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    Wildfire

    Wildfires are dangerous for all people living nearwoodlands.

    In the wild, wildfires are ignited by lightning. Butsome wildfires are caused by careless campers who

    did not extinguish their campfire or by walkerswho threw their cigarettes in the woods. 80% ofwildfires are caused by careless people.

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    Wildfires move forward rapidly, even more if windsblow and the weather is dry.

    To stop wildfires, firefighters use water bombers

    which carry water and drop it on wildfires.

    Wildfires do not only have bad effects. In fact,the many dead pin needles, leaves and tree trunks

    on the ground are burnt to ashes by wildfires.These ashes are full of minerals and help thegrowth of new trees.

    By burning trees, wildfires make gaps in the

    forest (called clearings). These clearings allow thesun to heat the ground up and help tree seeds togrow.

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    How to Prevent Wildfires

    Ensure that your campfires are always properlyextinguished. Never smoke in the woods.

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    Flood

    Floods happen when a watercourse overflows. Theycould be caused by rain, thaws or ice jams.

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    Heavy Rain

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    When it rains, water falling on the groundpenetrates it. But when the ground alreadycontains a lot of water, the falling rain could notseep through it. The water then starts flowingtoward a watercourse.

    When it rains a lot on a region, all water flowstoward the river, but this river can not contain it;therefore, the river overflows.

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    Thaw

    When spring arrives, snow and ice start to meltand the water flows toward the river. If thetemperature rises too rapidly, a lot of water isproduced in a short time; the river overflows and aflood happens.

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    Ice Jam

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    In spring, rivers thaw out and big chunks of icedetach themselves and drift on the river.

    Sometimes these chunks get jammed against abridge or rocks. Consequently, these chunks of iceform a kind of dam.

    When water can not flow through this dam, it

    tries to find an alternate course to reach theriver and, sometimes, this new course is a field,a road or a house basement

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    What to Do During a Flood

    With your parents, bring upstairs all objects ofthe basement that could be damaged by water. If

    your family is asked to evacuate, do soimmediately! The water level can rise faster than

    you think

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    Winter Storm

    There are many kinds of winter storm. Youprobably already know those happening during thewinter, like the snow storm and the ice storm.

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    Snow Storm

    The temperature must be sufficiently cold forsnow to fall and flakes to reach the ground. Whenwinds blow heavily and you can not see before you,it means that a blizzard is blowing.

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    What to Do During a Blizzard

    Go home! Many people lost themselves during

    major snow storms. Everything becomes white andit is hard to find your way back home

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    Thunderstorm

    Lightning

    During a thunderstorm, the air is charged withelectricity. A lightning is an electric dischargethat hits the ground at approximately 40 000km/s. Have you ever seen a bolt with forks? In

    fact, it is a series of lightning strikes takingthe same path, too quickly for the eye todistinguish between them!

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    Is the thunderstorm drawing near? To answerthis question, count the seconds between the

    lightning and the thunder clap. If the number ofseconds between the lightning and the thunderclap increases after each lightning, you canconclude that the thunderstorm is moving away.

    If the number of seconds diminishes, thethunderstorm is moving closer! Take shelter!

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    What to Do During a Thunderstorm If you are indoors, stay there until the end of the

    thunderstorm. Unplug all appliances, because they could bedamaged if a lightning strikes your house.

    Do not talk to the phone during a thunderstorm: you couldget a shock.

    If you are in the water, get out immediately.

    Beware! Lightning always strikes high and isolated points,like a tree in a field. Never shelter under a tree during athunderstorm, unless you are in the woods and shelteringunder the smallest trees. If you do not have access to ashelter, sit down, put you head on your knees and cover itwith your arms. Do not lie on the ground.

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    Hail

    Hails happen when drops of water freeze in cloudsand become small ice crystals. These crystals aretossed in all directions. They grow bigger asadditional layers of ice form on their surface, likeonion peelings. When hailstones are too heavy,they fall and it hails.

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    Hailstones have a minimal diameter of 5 mm andcan reach 10 cm, that is the diameter of agrapefruit! The smaller ice crystals are called ice

    pellets. Hailstones can be very big and fall at great speed

    (130 km/h), hurting people and causing damages,such as breaking windows, denting in cars, ruining

    harvests, etc.

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    What to Do During a Hail Storm

    Take shelter as soon as possible! When hails aresmall, they nip the skin: it is unpleasant, but not

    dangerous. When they are bigger, they can hurtyou and cause damages.

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    Tornado

    A tornado is a funnel-shaped storm windspinning around. A tornado could be verydestructive: its winds could speed up to 400km/h! Moreover, it is impossible to foresee itspath. It could switch directions. The Fujitascale is used to measure the strength of atornado.

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    Fujita Scale

    The Fujita scale measures the strength oftornadoes. It is comprised of 5 force levels:

    F-0Winds from 64 to 116 km/h. Damaged chimneysand broken branches.

    F-1 Winds from 117 to 180 km/h. Mobile homeslifted off their foundation.

    F-2

    Winds from 181 to 250 km/h. Mobile homes

    destroyed and trees torn.

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    F-3 Winds from 251 to 330 km/h. Torn roofs andwalls, trains overturned and cars moved.

    F-4 Winds from 331 to 420 km/h. Heavy wallsmoved.

    F-5 Winds from 421 to 512 km/h. Houses liftedoff their foundations and cars moved over several

    metres (up to 100 metres).

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    What to Do During a Tornado If you are indoors, go downstairs, lie under a large

    piece of furniture, turn away from the windows and

    cover your head with your arms.

    If there is no basement, take a similar shelter in awindow-less room located in the centre of the building,if possible.