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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.

If you are outdoors, lie face down on the ground in aditch or under a viaduct and cover your head with your

arms.Beware! Never chase a tornado because it couldsuddenly change directions and come toward you.


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Hurricane

Hurricanes are enormous tropical storms arisingout of the sea. Their violent winds areaccompanied by a lot of rain. They are calledouragans in France, typhoons in Asia and willy-willy in Australia.

Hurricanes could move rapidly. They spin aroundand have an eye in their centre. The eye is thecentre of the hurricane: this part is very calm asopposed to the edge, which has very bad weather.


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When a hurricane strikes, there is a lot of rain andwind. Suddenly, all those things disappear! The

weather is turning nice, winds diminish and rainstops: you are in the eye of the hurricane. Butbeware! Once it is gone, the bad weather startsagain with reversed winds.

Hurricanes usually affect warm regions, becausethese storms can not stand cold water. But,sometimes, some hurricanes do reach theMaritimes and Qubec. Fortunately, that does not

happen often.


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Hurricanes Name

The name of the hurricanes is chosen from a list

of first names in alphabetical order. Female andmale names are chosen alternatively. For example,the first hurricane of the year will be calledAlexandra, the second Bernard, the thirdCatherine, etc.


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What to Do During a Hurricane

Go inside your house as soon as you learn about the

hurricane. Then go downstairs and lie under a largepiece of furniture. If there is no such place in thebasement, take a similar shelter in a window-lessroom located in the centre of the building, ifpossible.

Beware if the storm dies down! This could be theeye of the hurricane. Listen to the radio to know ifthe hurricane is moving away.


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Earthquake


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An earthquake happens when the earths crustmoves. You can then feel the ground shaking.Vibrations originate from a point called epicentre.

Earthquakes strength varies a lot for each event.Some times, they are hardly felt and some othertimes, they are strong enough to cause fixedobjects to fall and houses to collapse! Earthquakescan also cause tidal waves, also called tsunamis.
http://www.msp.gouv.qc.ca/jeunesse/catastrophe/toutsecuritecivile/tsunami_en.htmlhttp://www.msp.gouv.qc.ca/jeunesse/catastrophe/toutsecuritecivile/tsunami_en.html


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It is possible to measure the strength of anearthquake with the Richter scale of aseismograph. The Richter scale was created by an

American seismologist named Charles F. Richter. The Richter scale ranges from 0 (no earthquake)

to 9 (largest earthquake ever recorded). For eachlevel, the earthquake is ten times stronger. Forexample, an earthquake in the range of 3 on theRichter scale is ten times stronger than anearthquake in the range of 2 on the same scale.


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Richter Scale

M 1: Usually not felt.

M 2: Usually not felt.

M 3: Often felt, no damage.

M 4: Often felt, no damage.

M 5: Moderate earthquake. Easily felt. Minor

damages to buildings near the epicentre. M 6: Strong earthquake. Damages to weak

buildings located several kilometres from theepicentre


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M 7: Major earthquake. Many damages to buildingslocated hundreds of kilometres from theepicentre.

M 8: Giant earthquake. Heavy property damagesand many dead and hurt persons on hundreds ofkilometres.

M 9: Super earthquake. Very rare. It destroysnearly everything in the region of the epicentre onthousands of kilometres.

h E h k


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What to Do During an Earthquake

If you are indoors, lie under a large piece offurniture, like a table or a desk, and cover your

head with your arms.Turn away from windows and mirrors: if theybroke, their splinters could harm you. If you areoutdoors, move away from buildings, phone poles

and electric wires; in other words, get clear of allinjury risks.

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Volcano

A l i i h i j fi d l


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A volcano is erupting when it ejects fire and lava.But volcanoes could also release dust, ashes androcks. Volcanoes also produce gases: water vapour,

carbon dioxide, sulphur dioxide, etc. In some degree, volcanoes are the chimneys of the

Earth, allowing the magma to flow. The magma risesslowly in the volcano (1 km/h), causing small

earthquakes and, sometimes, tidal waves

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Volcanoes are usually found along the edges oftectonic plates, but also elsewhere. There is noactive volcano in Qubec. An active volcano is a

volcano which erupted in the last 100 years. Magma

The magma is molten rocks, that means rocksmelted into liquid state due to the hightemperature and pressure in the Earths core.When the magma spills from a volcano, it is calledlava.
http://www.msp.gouv.qc.ca/jeunesse/catastrophe/toutsecuritecivile/tremblement_en.htmlhttp://www.msp.gouv.qc.ca/jeunesse/catastrophe/toutsecuritecivile/tremblement_en.html


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Tsunami

Tid l t i i f


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Tidal waves, or tsunamis, are a series of enormouswaves. Tsunamis originate from the sea and arecaused by earthquakes or by the eruption of

underwater volcanoes. These waves are breakingvery fast and could rise up to 30 m high.

These giant waves are very impressive, but alsolethal: they destroy everything in their path, from

houses to skyscrapers. Seeing the first of thewaves from the coast means that it is already toolate to attempt an escape.

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Rockslide and Landslide

Rockslide is a downward and rapid movement ofnewly detached pieces of bedrock.

Landslides are ground and rock movements. Theyoccur most commonly where the ground is made ofsoft material, like clay.

When ground or cliffs collapsed, one calls them"scree".

The difference between a rockslide and a landslideis what is sliding:

rockslide: big rocks and cliffs landslide: ground and mud


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What to Do to Avoid Rockslide and Landslide

Of course, if you live outside rockslide hazardzones, accident risks will also be lower. To reducerockslide (or collapse) risks, rocksheds similar tosnowsheds, as for avalanches, could be installed.

Another way is to trigger controlled rockslide risks,

which means to cause less strong rocks to fall downafter being sure nobody or nothing will be hit bythem.
http://www.msp.gouv.qc.ca/jeunesse/catastrophe/toutsecuritecivile/avalanche_en.htmlhttp://www.msp.gouv.qc.ca/jeunesse/catastrophe/toutsecuritecivile/avalanche_en.html

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