Natural Disasters 1

7/29/2019 Natural Disasters 1

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Natural disastersEARTHQUAKEVOLCANOFLOODSHURRICANETORNADOTSUNAMIWILDFIREDROUGHTAVALANCHELANDSLIDE


3/14

Earthquakes

An earthquake(also known as a

quake, tremor or temblor) is the

result of a sudden release of

energy in the Earth's crust that

creates seismic waves. An

earthquake is caused by a suddenslip on a fault. The tectonic plates

are always slowly moving, but

they get stuck at their edges due

to friction. When the stress on theedge overcomes the friction, there

is an earthquake that releases

energy in waves that travel

through the earth's crust and

cause the shaking.
http://www.google.co.in/url?sa=i&rct=j&q=earthquake&source=images&cd=&cad=rja&docid=PjrfqIb2QR0neM&tbnid=1OAMvd-1zoLIaM:&ved=0CAUQjRw&url=http://www.sanandreasfault.org/EQS.html&ei=x-gEUufbNoaYrAfW9oDYDg&bvm=bv.50500085,d.bmk&psig=AFQjCNHZsIdgWWgry2P13NPFhiSlBvmtuw&ust=1376139836422527


4/14

volcano

A volcano is an opening, or rupture, in a

planet's surface or crust, which allowshot magma, volcanic ash and gases to

escape from the magma chamber below

the surface. Volcanic activity frequently

occurs at the boundaries of the Earth's

tectonic plates which are a series of largeblocks moving between each other.

A supervolcano is a volcano capable of

producing a volcanic eruption with an ejecta

volume greater than 1,000 km

3

(240 cu mi).This is thousands of times larger than normal

volcanic eruptions. Supervolcanoes can occur

when magma in the mantle rises into the crust

from a hotspot but is unable to break through

the crust.
http://www.google.co.in/url?sa=i&rct=j&q=volcano&source=images&cd=&cad=rja&docid=bkkNxddbp4wSWM&tbnid=ii8jbKkeDy4OcM:&ved=&url=http://listdose.com/top-10-most-active-volcanoes-in-the-worlds/&ei=le0EUsC2NMfjrAeX9YGYBA&bvm=bv.50500085,d.bmk&psig=AFQjCNHnZVaXC6CzQkvp69YaAoQ3UcKeug&ust=1376141078100996http://www.google.co.in/url?sa=i&rct=j&q=supervolcano&source=images&cd=&cad=rja&docid=GunL3X3djU0gpM&tbnid=fJSwvSO6kG1-_M:&ved=&url=http://its-interesting.com/2011/01/28/supervolcano/&ei=Su0EUpKEHIjOrQetlYHYDg&bvm=bv.50500085,d.bmk&psig=AFQjCNFBYcsguDB5JgaNBpvBmCH6EgN_gQ&ust=1376141003041709


5/14

Floods

Aflood is an overflow of water thatsubmerges land which is normally

dry. Flooding may occur as an

overflow of water from water bodies,

such as a river or lake, in which the

water overtops or breaks levees,resulting in some of that water

escaping its usual boundaries. Some

floods develop slowly, while others

such as flash floods, can develop in

just a few minutes and withoutvisible signs of rain. Additionally,

floods can be local, impacting a

neighbourhood or community, or very

large, affecting entire river basins
http://www.google.co.in/url?sa=i&rct=j&q=flood&source=images&cd=&cad=rja&docid=KW4VM6th6Ch-FM&tbnid=sQqufoCQkS0PyM:&ved=0CAUQjRw&url=http://www.un.org/apps/news/story.asp?NewsID=40068&ei=ufIEUpKsEMOmrAfqjYCQDA&bvm=bv.50500085,d.bmk&psig=AFQjCNHvmBg4TW1UWYXWiN2gNjzHxJ2QAw&ust=1376142372176268


6/14

Hurricane

Hurricanes, tropical cyclones, and

typhoons are different names forthe same phenomenon: a cyclonic

storm system that forms over the

oceans. It is caused by evaporated

water that comes off of the ocean

and becomes a storm. The CoriolisEffect causes the storms to spin,

and a hurricane is declared when

this spinning mass of storms

attains a wind speed greater than

74 mph. Hurricane is used forthese phenomena in the Atlantic

and eastern Pacific Oceans,

tropical cyclone in the Indian,

and typhoon in the western

Pacific.
http://www.google.co.in/url?sa=i&rct=j&q=hurricane+-+natural+disaster&source=images&cd=&cad=rja&docid=I5s4wKwBerPM6M&tbnid=seffZTKbpIH5mM:&ved=0CAUQjRw&url=http://www.projectshum.org/NaturalDisasters/hurricanes.html&ei=fPUEUv2AOoK8rAfKpYGwCQ&bvm=bv.50500085,d.bmk&psig=AFQjCNFDseMt66YssSvupLBETPqsIH-obg&ust=1376143000672433


7/14

TornadoTornadoes are violent, rotating

columns of air which can blow atspeeds between 50 and 300 mph,

and possibly higher. Tornadoes

can occur one at a time, or can

occur in large tornado outbreaks

along squall lines or in other largeareas of thunderstorm

development. Tornado conditions

are caused when different

temperatures and humidity meet

to form thunderclouds. Tornadoes

form in unusually violent

thunderstorms when there is

sufficient instability and wind

shear present in the loweratmosphere.
http://www.google.co.in/url?sa=i&rct=j&q=tornado&source=images&cd=&cad=rja&docid=QxdWQ0mQ39SCEM&tbnid=-JQthyEnrWdYUM:&ved=0CAUQjRw&url=http://science.howstuffworks.com/nature/natural-disasters/eye-of-tornado.htm&ei=nvkEUo21F8bLrQek_oC4DA&bvm=bv.50500085,d.bmk&psig=AFQjCNFjQnYsJpcVOOZVNKy5wdB_0v7bLA&ust=1376144022638328http://www.google.co.in/url?sa=i&rct=j&q=tornado&source=images&cd=&cad=rja&docid=QphGNFPUW-UNnM&tbnid=eYbTC56M-sPPwM:&ved=0CAUQjRw&url=http://raccoonvalleyradio.com/2013/03/city-of-stuart-to-participate-in-statewide-tornado-drill/&ei=IfkEUvysO8fMrQe4y4DQDA&bvm=bv.50500085,d.bmk&psig=AFQjCNFjQnYsJpcVOOZVNKy5wdB_0v7bLA&ust=1376144022638328


8/14

Tsunami

A tsunami is a series of waves

created when a body of water,such as an ocean, is rapidly

displaced. Earthquakes, mass

movements above or below

water, volcanic eruptions and

other underwater explosions,landslides, large meteorite

impacts comet impacts and

testing with nuclear weapons at

sea all have the potential to

generate a tsunami. A tsunami

is not the same thing as a tidal

wave, which will generally have

a far less damaging effect than a

Tsunami.
http://www.google.co.in/url?sa=i&rct=j&q=tsunami&source=images&cd=&cad=rja&docid=c-ewTf6tWO5k6M&tbnid=T9F4HyKe21XPBM:&ved=0CAUQjRw&url=http://bernews.com/2012/12/bermuda-factors-in-maine-tsunami-planning/&ei=SPwEUr_PKoeHrAe1_4C4Bg&bvm=bv.50500085,d.bmk&psig=AFQjCNFMqedmyX8WhaEtbyh8Aa0MyOBlww&ust=1376144820988251http://www.google.co.in/url?sa=i&rct=j&q=tsunami&source=images&cd=&cad=rja&docid=5xngEOCl2649AM&tbnid=YVOtyBDs4CA9VM:&ved=0CAUQjRw&url=http://esl-bits.net/listening/Media/2011-06-16/Tsunamis/&ei=ufsEUrzlIILUrQei64G4BA&bvm=bv.50500085,d.bmk&psig=AFQjCNFCK46SceeJP46bIFSZ11qDFHWV8w&ust=1376144685162360


9/14

WildfireWildfires, or forest fires, are uncontrolled

fires burning in wildland areas.Common causes include lightning,

human carelessness, arson, volcano

eruption, and pyroclastic cloud from

active volcano. The can be a threat to

those in rural areas and also towildlife. Wildfires can also produce

ember attacks, where floating embers

set fire to buildings at a distance from

the fire itself. Strategies of wildfire

prevention, detection, and suppressionhave varied over the years, and

international wildfire management

experts encourage further development

of technology and research.[
http://en.wikipedia.org/wiki/Wildfirehttp://www.google.co.in/url?sa=i&rct=j&q=wildfire&source=images&cd=&cad=rja&docid=MxNIekfFdvpLVM&tbnid=zA9BsJaQrSq3BM:&ved=0CAUQjRw&url=http://environment.nationalgeographic.com/environment/natural-disasters/wildfires/&ei=CQAFUrKzAcuOrgfb0oDwBA&bvm=bv.50500085,d.bmk&psig=AFQjCNG3hGsTfcsCIY4-Hq1CTK9Y4fJKsA&ust=1376145788661888http://www.google.co.in/url?sa=i&rct=j&q=wildfire&source=images&cd=&cad=rja&docid=jkZPsdjZvcml5M&tbnid=MBuLvTwyekH81M:&ved=0CAUQjRw&url=http://www.mylifeoutdoors.com/2011/04/wildfire-hiking-safety-what-to-do-if.html&ei=Jv8EUt_NG8OQrQfb-ICYAg&bvm=bv.50500085,d.bmk&psig=AFQjCNH8VGULjL952m_8ziIkhoGMlQ1cfA&ust=1376145530333945http://en.wikipedia.org/wiki/Wildfire


10/14

Drought

A drought is an extended period of

months or years when a regionsuffers a severe deficiency in its

water supply. Generally, this occurs

when a region receives consistently

below average rainfall. It can have

a substantial impact on the

ecosystem and agriculture of the

affected region. Although droughts

can persist for several years, even a

short, intense drought can causesignificant damage and harm the

local economy. This global

phenomenon has a widespread

impact on agriculture.
http://www.google.co.in/url?sa=i&source=images&cd=&cad=rja&docid=v1fOUYo68_EJzM&tbnid=4OBYbcwNwF-13M:&ved=0CAgQjRwwAA&url=http://www.telegraph.co.uk/earth/environment/climatechange/9677724/Droughts-steady-since-1950s.html&ei=ywEFUt7aH8PprAfu5YC4Cg&psig=AFQjCNE8KuwUVbK27IkkLGqwA32kuG4PCg&ust=1376146251682011http://www.google.co.in/url?sa=i&rct=j&q=drought&source=images&cd=&cad=rja&docid=IVpkHXPxVPdjQM&tbnid=Zdk86ppLGdfbrM:&ved=0CAUQjRw&url=/url?sa=i&rct=j&q=drought&source=images&cd=&cad=rja&docid=IVpkHXPxVPdjQM&tbnid=Zdk86ppLGdfbrM:&ved=&url=http://drpinna.com/worlds-largest-aquifer-is-running-dry-16757/drought-6&ei=bgEFUt-UIYK4rAeumYH4Aw&bvm=bv.50500085,d.bmk&psig=AFQjCNEEK-DLlJaEOExEub_89zdb-taoNA&ust=1376146158742595&ei=kwEFUoOdLoeLrQeo_oDoCw&bvm=bv.50500085,d.bmk&psig=AFQjCNEEK-DLlJaEOExEub_89zdb-taoNA&ust=1376146158742595


11/14

AvalancheAn avalanche (also called a snowslide or

snowslip) is a rapid flow of snowdown a slope. Avalanches are

typically triggered in a starting zone

from a mechanical failure in the

snowpack (slab avalanche) when the

forces on the snow exceed its strengthbut sometimes only with gradually

widening (loose snow avalanche).

After initiation, avalanches usually

accelerate rapidly and grow in mass

and volume as they entrain more

snow. If the avalanche moves fastenough some of the snow may mix

with the air forming a powder snow

avalanche, which is a type of gravity

current.
http://www.google.co.in/url?sa=i&rct=j&q=avalanche&source=images&cd=&cad=rja&docid=x9E0wzUQq6xsrM&tbnid=V_dmFg5v-uHEbM:&ved=0CAUQjRw&url=http://www.piquenewsmagazine.com/whistler/sea-to-sky-corridor-avalanche-danger-rating-creeping-up/Content?oid=2446179&ei=CQQFUoLxNMSPrgfQooHADg&bvm=bv.50500085,d.bmk&psig=AFQjCNGer3XXGJbbGuCKoqB3BXc0L2DMWw&ust=1376146801035608


12/14

Landslide

A landslide or landslip is a geological

phenomenon which includes a widerange of ground movements, such as

rockfalls, deep failure of slopes and

shallow debris flows, which can occur

in offshore, coastal and onshore

environments. Although the action ofgravity is the primary driving force for

a landslide to occur, there are other

contributing factors affecting the

original slope stability. Typically, pre-

conditional factors build up specific

sub-surface conditions that make the

area/slope prone to failure, whereas

the actual landslide often requires a

trigger before being released.
http://www.google.co.in/url?sa=i&source=images&cd=&cad=rja&docid=B_9qpiM6heLKgM&tbnid=-qppVgoq4KJ4dM:&ved=0CAgQjRwwAA&url=http://landslides.usgs.gov/research/other/centralamerica.php&ei=OgYFUtfvBI6urAf_8oDQDw&psig=AFQjCNGQZ9Ij-BmkPIms9Pso4E8H_XpREg&ust=1376147386233855http://www.google.co.in/url?sa=i&rct=j&q=landslides&source=images&cd=&cad=rja&docid=HcsuuUsJeo8D9M&tbnid=Cz5SNgOsJiB9hM:&ved=0CAUQjRw&url=http://landslides.usgs.gov/regional/inventory/utah/&ei=AgYFUtrPGdHRrQfL1IDIAg&bvm=bv.50500085,d.bmk&psig=AFQjCNHd20e2_WBmDMqmI56WRnuRwlwBhQ&ust=1376147305875475


13/14

Weather EventsLike drought, an increase in severe

weather events has been recorded in thelast 100 years by the National Climatic

Data Center. While notification systems

are in place, vulnerabilities still exist for

property damage and crop loss.

Development has also complicated the

effects of such events. An increase indevelopment leads to a decrease in

wetlands and an increase in impervious

surfaces such as roads and driveways.

This creates a scenario for floods and

flash flooding. As with drought,

scientists believe a link between global

warming and climate changes exists.


14/14

Documents

Natural Disasters 1