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A rope tornado in its dissipatingstage, Tecumseh, Oklahoma.

A daytime wildfire in California.

Natural disasterFrom Wikipedia, the free encyclopedia

For the Anathema album, see A Natural Disaster. For the songs, see Natural Disaster (Plain White T'ssong) and Natural Disaster (Example song).

A natural disaster is a major adverse event resulting from naturalprocesses of the Earth; examples include floods, volcanic eruptions,earthquakes, tsunamis, and other geologic processes. A naturaldisaster can cause loss of life or property damage,[1] and typicallyleaves some economic damage in its wake, the severity of whichdepends on the affected population's resilience, or ability torecover.[2]

An adverse event will not rise to the level of a disaster if it occurs inan area without vulnerable population.[3][4] In a vulnerable area,however, such as San Francisco and Nepal, an earthquake can havedisastrous consequences and leave lasting damage, requiring yearsto repair.

In 2012, there were 905 natural disasters worldwide, 93% of whichwere weather­related disasters. Overall costs were US$170 billionand insured losses $70 billion. 2012 was a moderate year. 45% weremeteorological (storms), 36% were hydrological (floods), 12% wereclimatological (heat waves, cold waves, droughts, wildfires) and 7%were geophysical events (earthquakes and volcanic eruptions).Between 1980 and 2011 geophysical events accounted for 14% ofall natural catastrophes.[5]

Contents

1 Geological disasters1.1 Avalanches and landslides1.2 Earthquakes1.3 Sinkholes1.4 Volcanic eruptions

2 Hydrological disasters2.1 Floods2.2 Limnic eruptions2.3 Tsunami

3 Meteorological disasters3.1 Blizzards3.2 Cyclonic storms

3.2.1 Tropical cyclones3.2.2 Extratropical cyclones

3.3 Droughts

3.4 Hailstorms

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3.4 Hailstorms3.5 Heat waves3.6 Tornadoes

4 Wildfires5 Health disasters

5.1 Epidemics6 Space disasters

6.1 Impact events6.2 Solar flare

7 Protection by international law8 See also9 References10 External links

Geological disasters

Avalanches and landslides

See also: List of avalanches

During World War I, an estimated 40,000 to 80,000 soldiers died as a result of avalanches during themountain campaign in the Alps at the Austrian­Italian front. Many of the avalanches were caused byartillery fire.[6][7]

Earthquakes

See also: Lists of earthquakes

An earthquake is the result of a sudden release of energy in the Earth's crust that creates seismic waves. Atthe Earth's surface, earthquakes manifest themselves by vibration, shaking and sometimes displacement ofthe ground.Earthquakes are caused mostly by slippage within geological faults, but also by other eventssuch as volcanic activity, landslides, mine blasts, and nuclear tests. The underground point of origin of theearthquake is called the focus. The point directly above the focus on the surface is called the epicenter.Earthquakes by themselves rarely kill people or wildlife. It is usually the secondary events that they trigger,such as building collapse, fires, tsunamis (seismic sea waves) and volcanoes, that are actually the humandisaster. Many of these could possibly be avoided by better construction, safety systems, early warning andplanning.

Sinkholes

See also: Sinkholes § Notable examples

When natural erosion or human mining makes the ground too weak to support the structures built on it, theground can collapse and produce a sinkhole. For example, the 2010 Guatemala City sinkhole which killedfifteen people was caused when heavy rain from Tropical Storm Agatha, diverted by leaking pipes into apumice bedrock, led to the sudden collapse of the ground beneath a factory building.

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The Red Lake (Croatia).

Artist's impression of the volcaniceruptions that formed the DeccanTraps in India.

Volcanic eruptions

Main articles: List of largest volcanic eruptions and Types of volcanic eruptions

Volcanoes can cause widespread destruction and consequent disaster in several ways. The effects includethe volcanic eruption itselfthat may cause harmfollowing the explosion ofthe volcano or the fall ofrock. Second, lava may beproduced during the eruptionof a volcano. As it leaves thevolcano, the lava destroysmany buildings, plants andanimals it encounters. Third,volcanic ash generallymeaning the cooled ash ­may form a cloud, and settlethickly in nearby locations.When mixed with water this

forms a concrete­like material. In sufficient quantity ash may causeroofs to collapse under its weight but even small quantities willharm humans if inhaled. Since the ash has the consistency of groundglass it causes abrasion damage to moving parts such as engines.The main killer of humans in the immediate surroundings of avolcanic eruption is the pyroclastic flows, which consist of a cloudof hot volcanic ash which builds up in the air above the volcano and rushes down the slopes when theeruption no longer supports the lifting of the gases. It is believed that Pompeii was destroyed by apyroclastic flow. A lahar is a volcanic mudflow or landslide. The 1953 Tangiwai disaster was caused by alahar, as was the 1985 Armero tragedy in which the town of Armero was buried and an estimated 23,000people were killed.

A specific type of volcano is the supervolcano. According to the Toba catastrophe theory, 75,000 to 80,000years ago a supervolcanic event at Lake Toba reduced the human population to 10,000 or even 1,000breeding pairs, creating a bottleneck in human evolution.[8] It also killed three­quarters of all plant life inthe northern hemisphere. The main danger from a supervolcano is the immense cloud of ash, which has adisastrous global effect on climate and temperature for many years.

Hydrological disasters

It is a violent, sudden and destructive change either in quality of earth's water or in distribution ormovement of water on land below the surface or in atmosphere.

Floods

See also: List of floods

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The Limpopo River during the 2000Mozambique flood

A cow suffocated bygases after a limniceruption at Lake Nyos

A flood is an overflow of water that "submerges" land.[9] The EU Floods Directive defines a flood as atemporary covering by water of land not normally covered by water.[10] In the sense of "flowing water", theword may also be applied to the inflow of the tides. Flooding may result from the volume of water within abody of water, such as a river or lake, which overflows causing the result that some of the water escapes itsusual boundaries.[11] While the size of a lake or other body of water will vary with seasonal changes inprecipitation and snow melt, it is not a significant flood unless the water covers land used by man like avillage, city or other inhabited area, roads, expanses of farmland,etc.

Limnic eruptions

Main article: Limnic eruption

A limnic eruption occurs when a gas, usually CO2, suddenly eruptsfrom deep lake water, posing the threat of suffocating wildlife,livestock and humans. Such an eruption may also cause tsunamis inthe lake as the rising gas displaces water. Scientists believelandslides, volcanic activity, or explosions can trigger such aneruption. To date, only two limnic eruptions have been observed andrecorded. In 1984, in Cameroon, a limnic eruption in Lake Monoun caused thedeaths of 37 nearby residents, and at nearby Lake Nyos in 1986 a much largereruption killed between 1,700 and 1,800 people by asphyxiation.

Tsunami

Main article: Tsunami

A tsunami (plural: tsunamis or tsunami; from Japanese: 津波, lit. "harbourwave"; English pronunciation: /tsuːˈnɑːmi/), also known as a seismic sea waveor as a tidal wave, is a series of waves in a water body caused by thedisplacement of a large volume of water, generally in an ocean or a large lake.Tsunamis can be caused by undersea earthquakes such as the 2004 Boxing Daytsunami, or by landslides such as the one in 1958 at Lituya Bay, Alaska, or byvolcanic eruptions such as the ancient eruption of Santorini. On March 11,2011, a tsunami occurred near Fukushima, Japan and spread through thePacific.

Meteorological disasters

Main article: Meteorological disasters

Blizzards

Main article: Blizzard

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Young steer after a blizzard, March1966

Affected areas in the western Sahelbelt during the 2012 drought.

Blizzards are severe winter storms characterized by heavy snow and strong winds. When high winds stir upsnow that has already fallen, it is known as a ground blizzard. Blizzards can impact local economicactivities, especially in regions where snowfall is rare. The Great Blizzard of 1888 affected the UnitedStates, when many tons of wheat crops were destroyed, and in Asia, 2008 Afghanistan blizzard and the1972 Iran blizzard were also significant events.

Cyclonic storms

Tropical cyclones

See also: List of tropical cyclones

Cyclone, tropical cyclone, hurricane, and typhoon are differentnames for the same phenomenon, which is a cyclonic storm systemthat forms over the oceans. The deadliest hurricane ever was the1970 Bhola cyclone; the deadliest Atlantic hurricane was the GreatHurricane of 1780 which devastated Martinique, St. Eustatius andBarbados. Another notable hurricane is Hurricane Katrina, whichdevastated the Gulf Coast of the United States in 2005.

Extratropical cyclones

Main article: Extratropical cyclone

Extratropical cyclones, sometimes called mid­latitude cyclones, are a group of cyclones defined as synopticscale low pressure weather systems that occur in the middle latitudes of the Earth (outside the tropics) nothaving tropical characteristics, and are connected with fronts and horizontal gradients in temperature anddew point otherwise known as "baroclinic zones". As with tropical cyclones, they are known by differentnames in different regions (nor'easter, Pacific Northwest windstorms, European windstorm, East Asian­northwest Pacific storms, sudestada, and Australian east coast cyclones). The most intense extratropicalcyclones cause widespread disruption and damage to society, such as the storm surge of the North Sea floodof 1953 which killed 2251 people in the Netherlands and eastern England, the Great Storm of 1987 whichdamaged southern England and France, and the Columbus Day Storm of 1962 which struck the PacificNorthwest.

Droughts

Main article: Drought

Drought is unusual dryness of soil, resulting in crop failure andshortage of water for other uses, caused by significantly lowerrainfall than average over a prolonged period. Hot dry winds,shortage of water, high temperatures and consequent evaporation ofmoisture from the ground can contribute to conditions of drought.

Well­known historical droughts include the 1997–2009 Millenium Drought in Australia led to a watersupply crisis across much of the country. As a result, many desalination plants were built for the first time(see list). In 2011, the State of Texas lived under a drought emergency declaration for the entire calendar

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A large hailstone, about 6 cm (2.4 in)in diameter

A classic anvil­shaped, and clearly­developed Cumulonimbus incus

year and severe economic losses.[12] The drought caused the Bastrop fires.

Hailstorms

Main article: Hail

Hailstorms are falls of rain drops that arrive as ice, rather thanmelting before they hit the ground. A particularly damaginghailstorm hit Munich, Germany, on July 12, 1984, causing about 2billion dollars in insurance claims.

Heat waves

Main article: Heat wave

A heat wave is a period of unusually and excessively hot weather. The worst heat wave in recent historywas the European Heat Wave of 2003. A summer heat wave in Victoria, Australia, created conditionswhich fuelled the massive bushfires in 2009. Melbourne experienced three days in a row of temperaturesexceeding 40 °C (104 °F) with some regional areas sweltering through much higher temperatures. Thebushfires, collectively known as "Black Saturday", were partly the act of arsonists. The 2010 NorthernHemisphere summer resulted in severe heat waves, which killed over 2,000 people. It resulted in hundredsof wildfires which causing widespread air pollution, and burned thousands of square miles of forest.

Tornadoes

See also: List of tornadoes and tornado outbreaks

A tornado is a violent, dangerous, rotating column of air that is incontact with both the surface of the earth and a cumulonimbus cloudor, in rare cases, the base of a cumulus cloud. It is also referred to asa twister or a cyclone,[13] although the word cyclone is used inmeteorology in a wider sense, to refer to any closed low pressurecirculation. Tornadoes come in many shapes and sizes, but aretypically in the form of a visible condensation funnel, whose narrowend touches the earth and is often encircled by a cloud of debris anddust. Most tornadoes have wind speeds less than 110 miles per hour(177 km/h), are approximately 250 feet (80 m) across, and travel a few miles (several kilometers) beforedissipating. The most extreme tornadoes can attain wind speeds of more than 300 mph (480 km/h), stretchmore than two miles (3 km) across, and stay on the ground for dozens of miles (perhaps more than100 km).[14][15][16]

Wildfires

See also: List of forest fires

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Fallen trees caused by theTunguska meteoroid of theTunguska event in June 1908.

Wildfires are large fires which often start in wildland areas. Common causes include lightning and droughtbut wildfires may also be started by human negligence or arson. They can spread to populated areas and canthus be a threat to humans and property, as well as wildlife. Notable cases of wildfires were the 1871Peshtigo Fire in the United States, which killed at least 1700 people, and the 2009 Victorian bushfires inAustralia.

Health disasters

Epidemics

Main article: List of epidemics

An epidemic is an outbreak of a contractible disease that spreads through a human population. A pandemicis an epidemic whose spread is global. There have been many epidemics throughout history, such as theBlack Death. In the last hundred years, significant pandemics include the 1918 Spanish flu pandemic(killing an estimated 50 million people worldwide), the 1957–58 Asian flu pandemic, and the AIDSpandemic, which began in 1959. The 1968–69 Hong Kong water flu pandemic, the 2002­3 SARSpandemic, and the H1N1 Influenza (Swine Flu) Pandemic in 2009–2010 were also significant cases.

Space disasters

See also: Gamma ray burst

Impact events

Main article: Impact event

Asteroids that impact the Earth have led to several major extinctionevents, including one that created the Chicxulub crater 64.9 millionyears ago and associated with the demise of the dinosaurs. Scientistsestimate that the likelihood of death for a living human from a globalimpact event is comparable to death from airliner crash. One of thenotable impact events in modern times was the Tunguska event in June1908.

Solar flare

See also: Solar storm of 1859

A solar flare is a phenomenon where the sun suddenly releases a great amount of solar radiation, muchmore than normal. Some known solar flares include the X20 event on August 16, 1989,[17] and a similarflare on April 2, 2001.[17] The most powerful flare ever recorded occurred on November 4, 2003 (estimatedat between X40 and X45).[18]

Protection by international law

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International law, for example Geneva Conventions defines International Red Cross and Red CrescentMovement the Convention on the Rights of Persons with Disabilities, requires that "States shall take, inaccordance with their obligations under international law, including international humanitarian law andinternational human rights law, all necessary measures to ensure the protection and safety of persons withdisabilities in situations of risk, including the occurrence of natural disaster."[19] And further United NationsOffice for the Coordination of Humanitarian Affairs is formed by General Assembly Resolution 44/182.People displaced due to natural disasters are currently protected under international law (Guiding Principlesof International Displacement, Campala Convention of 2009).[20]

See also

Act of GodCivil defenseDisaster Risk ReductionEmergency managementEnvironmental disasterEnvironmental emergencyList of countries by natural disaster riskList of environmental disastersList of natural disasters by death tollWorld Conference on Disaster Reduction

References1. U.S. Billion­Dollar Weather and Climate Disasters (http://www.ncdc.noaa.gov/billions)2. G. Bankoff, G. Frerks, D. Hilhorst (eds.) (2003). Mapping Vulnerability: Disasters, Development and People.

ISBN 1­85383­964­7.3. D. Alexander (2002). Principles of Emergency planning and Management. Harpended: Terra publishing. ISBN 1­

903544­10­6.4. B. Wisner, P. Blaikie, T. Cannon, and I. Davis (2004). At Risk ­ Natural hazards, people's vulnerability anddisasters. Wiltshire: Routledge. ISBN 0­415­25216­4.

5. Natural Catastrophes in 2012 Dominated by U.S. Weather Extremes (http://www.worldwatch.org/natural­catastrophes­2012­dominated­us­weather­extremes­0) Worldwatch Institute May 29, 2013

6. Lee Davis (2008). "Natural Disasters (http://books.google.com/books?id=CRzMOYIuLJEC&pg=&dq&hl=en#v=onepage&q=&f=false)". Infobase Publishing. p.7. ISBN 0­8160­7000­8

7. "Avalanche!" (http://www.worldwar1.com/itafront/avalan.htm). WorldWar1.com. Retrieved 2015­01­12.8. Gibbons, Ann (19 January 2010). "Human Ancestors Were an Endangered Species"

(http://sciencenow.sciencemag.org/cgi/content/full/2010/119/2). ScienceNow.9. MSN Encarta Dictionary. Flood. (http://encarta.msn.com/encnet/features/dictionary/DictionaryResults.aspx?

refid=1861612277) Retrieved on 2006­12­28. Archived (http://www.webcitation.org/query?id=1257023547055729) 2009­10­31.

10. Directive 2007/60/EC Chapter 1 Article2 (http://eur­lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:2007:288:0027:0034:EN:PDF)

11. Glossary of Meteorology (June 2000). Flood. (http://amsglossary.allenpress.com/glossary/search?id=flood1)Retrieved on 2009­01­09.

12. Billion­Dollar Weather and Climate Disasters: Table of Events (http://www.ncdc.noaa.gov/billions/events)13. merriam­webster.com (http://www.merriam­webster.com/dictionary/cyclone)14. Wurman, Joshua (2008­08­29). "Doppler On Wheels" (http://cswr.org/dow/DOW.htm). Center for Severe

Weather Research. Retrieved 2009­12­13.

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Wikiquote has quotationsrelated to: Natural disasters

15. "Hallam Nebraska Tornado" (http://www.crh.noaa.gov/oax/archive/hallam/hallam.php). National WeatherService. National Oceanic and Atmospheric Administration. 2005­10­02. Retrieved 2009­11­15.

16. Roger Edwards (2006­04­04). "The Online Tornado FAQ" (http://www.spc.ncep.noaa.gov/faq/tornado/).National Weather Service. National Oceanic and Atmospheric Administration. Retrieved 2006­09­08.

17. "Sun Unleashes Record Superflare, Earth Dodges Solar Bullet"(http://www.sciencedaily.com/releases/2001/04/010404081121.htm). ScienceDaily. April 4, 2011. Retrieved2011­08­27.

18. "Biggest Solar Flare ever recorded"(https://web.archive.org/20110804064530/http://www.nasca.org.uk:80/Strange_Maps/solar/Solar_Flare/solar_flare.html). National Association for Scientific and Cultural Appreciation. 2004. Archived from the original(http://www.nasca.org.uk/Strange_Maps/solar/Solar_Flare/solar_flare.html) on August 4, 2011. Retrieved2011­08­27.

19. Article 11 of the Convention on the Rights of Persons with Disabilities20. Terminski, Bogumil, Towards Recognition and Protection of Forced Environmental Migrants in the Public

International Law: Refugee or IDPs Umbrella (December 1, 2011). Policy Studies Organization (PSO) Summit,December 2011.

External links

"Natural Disasters News"(http://www.naturaldisastersnews.net). Ubyrisk. Worldwidenews site focused on natural disasters, mitigation and climatechanges news"Global Risk Identification Program (GRIP)" (http://www.gripweb.org). GRIP."World Bank's Hazard Risk Management" (http://go.worldbank.org/BCQUXRXOW0). World Bank."Disaster News Network" (http://www.disasternews.net/). Retrieved 2006­11­05. US news sitefocused on disaster­related news."EM­DAT International Disaster Database" (http://www.em­dat.net). Retrieved 2006­11­05. Includescountry profiles, disaster profiles and a disaster list."Global Disaster Alert and Coordination System" (http://www.gdacs.org). European Commission andUnited Nations website initiative."Natural Disaster and Extreme Weather. Searchable Information Center"(http://site.ebrary.com/lib/disaster/home.action). Ebrary.

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