Editing Natural disaster (section)

=== Storms and heavy rain ===

==== Floods ====
{{main|Flood}}
{{see also|List of floods}}[[File:Limpopo.jpg|thumb|The [[Limpopo River]] during the [[2000 Mozambique flood]]]]

A [[flood]] is an overflow of water that 'submerges' land.<ref>MSN Encarta Dictionary. [http://encarta.msn.com/encnet/features/dictionary/DictionaryResults.aspx?refid=1861612277 Flood.] {{Webarchive|url=https://web.archive.org/web/20110204203836/http://encarta.msn.com/encnet/features/dictionary/DictionaryResults.aspx?refid=1861612277|date=2011-02-04}} Retrieved on 2006-12-28. 2009-10-31.</ref> The EU [[Floods Directive]] defines a flood as a temporary covering of land that is usually dry with water.<ref>{{cite web |title=Directive 2007/60/EC Chapter 1 Article2 |url=http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:2007:288:0027:0034:EN:PDF |url-status=live |archive-url=https://web.archive.org/web/20151106094442/http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:2007:288:0027:0034:EN:PDF |archive-date=2015-11-06 |access-date=2011-11-14}}</ref> In the sense of 'flowing water', the word may also be applied to the inflow of the [[tides]]. Flooding may result from the volume of a body of water, such as a [[river]] or [[lake]], becoming higher than usual, causing some of the water to escape its usual boundaries.<ref>Glossary of Meteorology (June 2000). [http://amsglossary.allenpress.com/glossary/search?id=flood1 Flood.] {{webarchive|url=https://web.archive.org/web/20070824054504/http://amsglossary.allenpress.com/glossary/search?id=flood1|date=2007-08-24}} Retrieved on 2009-01-09.</ref> While the size of a lake or other body of water will vary with seasonal changes in precipitation and snow melt, a flood is not considered significant unless the water covers land used by humans, such as a village, city or other inhabited area, roads or expanses of farmland.

==== Thunderstorms ====
[[File:Cumulonimbus NOAA gov.jpg|thumb|right|A classic anvil-shaped, and clearly-developed [[Cumulonimbus incus]]]]
{{main|Thunderstorm|Lightning}}

Severe storms, dust clouds and volcanic eruptions can generate [[lightning]]. Apart from the damage typically associated with storms, such as winds, hail and flooding, the lightning itself can damage buildings, ignite fires and kill by direct contact. Most deaths from lightning occur in the poorer countries of the Americas and Asia, where lightning is common and [[adobe]] [[mud brick]] housing provides little protection.<ref>{{cite news |date=31 July 2015 |title=Deadly lightning strike in Mexico reveals plight of poorest citizens |url=https://www.theguardian.com/world/2015/jul/31/deadly-lightning-mexico-government-failure |url-status=live |archive-url=https://web.archive.org/web/20170106110244/https://www.theguardian.com/world/2015/jul/31/deadly-lightning-mexico-government-failure |archive-date=6 January 2017 |access-date=17 December 2016 |work=The Guardian}}</ref>

==== Tropical cyclone ====
{{see also|Tropical cyclones and climate change}}
[[Typhoon]], [[cyclone]], [[cyclonic storm]] and [[hurricane]] are different names for the same phenomenon: a [[tropical storm]] that forms over an ocean. It is caused by evaporated [[water]] that comes off of the [[ocean]] and becomes a [[storm]]. It is characterized by strong winds, heavy rainfall and thunderstorms. The determining factor on which term is used is based on where the storm originates. In the Atlantic and Northeast Pacific, the term "hurricane" is used; in the Northwest Pacific, it is referred to as a "typhoon"; a "cyclone" occurs in the South Pacific and Indian Ocean.

The deadliest hurricane ever was the [[1970 Bhola cyclone]]; the deadliest Atlantic hurricane was the [[Great Hurricane of 1780]], which devastated Martinique, St. Eustatius and Barbados. Another notable hurricane is [[Hurricane Katrina]], which devastated the Gulf Coast of the United States in 2005. Hurricanes may [[Tropical cyclones and climate change|become more intense and produce more heavy rainfall]] as a consequence of human-induced [[climate change]].

==== Tornadoes ====
[[File:Shoal Creek Valley Alabama Tornado April 27, 2011.jpg|thumb|right|A [[2011 Shoal Creek Valley–Ohatchee tornado|killer tornado in Alabama]] photographed during the [[2011 Super Outbreak]], the most intense tornado outbreak on record.]]
{{see also|List of tornadoes and tornado outbreaks}}

A [[tornado]] is a violent and dangerous rotating column of air that is in contact with both the surface of the Earth and a [[cumulonimbus cloud]], or, in rare cases, the base of a [[cumulus cloud]]. It is also referred to as a ''twister'' or a ''cyclone'',<ref>{{cite web |title=Definition of CYCLONE |url=https://www.merriam-webster.com/dictionary/cyclone |url-status=live |archive-url=https://web.archive.org/web/20210105190603/https://www.merriam-webster.com/dictionary/cyclone |archive-date=2021-01-05 |access-date=2020-12-29 |publisher=Merriam-Webster}}</ref> although the word [[cyclone]] is used in meteorology in a wider sense to refer to any closed [[low pressure area|low pressure]] circulation. Tornadoes come in many shapes and sizes but typically take the form of a visible [[funnel cloud|condensation funnel]], the narrow end of which touches the Earth and is often encircled by a cloud of [[debris]] and [[dust]]. Tornadoes can occur one at a time, or can occur in large [[tornado outbreak]]s associated with [[supercell]]s or in other large areas of thunderstorm development.

Most tornadoes have wind speeds of less than {{convert|110|mph|km/h|sigfig=2|order=flip|abbr=on}}, are approximately {{convert|250|ft|m|round=5|order=flip|abbr=on}} across, and travel a few kilometers before dissipating. The [[Tornado records#Largest and most powerful tornadoes|most extreme tornadoes]] can attain wind speeds of more than {{convert|300|mph|km/h|order=flip|abbr=on}}, attain a width exceeding {{convert|2|mi|km|0|order=flip|abbr=on}} across, and stay on the ground for perhaps more than {{convert|100|km|mi|sigfig=1|abbr=on}}.<ref name="fastest wind">{{cite web |author=Wurman, Joshua |date=2008-08-29 |title=Doppler on Wheels |url=http://cswr.org/dow/DOW.htm |url-status=dead |archive-url=https://web.archive.org/web/20070205124033/http://www.cswr.org/dow/dow.htm |archive-date=2007-02-05 |access-date=2009-12-13 |publisher=Center for Severe Weather Research}}</ref><ref name="widest tornado">{{cite web |date=2005-10-02 |title=Hallam Nebraska Tornado |url=http://www.crh.noaa.gov/oax/archive/hallam/hallam.php |url-status=live |archive-url=https://web.archive.org/web/20140820095200/http://www.crh.noaa.gov/oax/archive/hallam/hallam.php |archive-date=2014-08-20 |access-date=2009-11-15 |work=[[National Weather Service]] |publisher=[[National Oceanic and Atmospheric Administration]]}}</ref><ref name="SPC FAQ">{{cite web |author=Roger Edwards |date=2006-04-04 |title=The Online Tornado FAQ |url=http://www.spc.ncep.noaa.gov/faq/tornado/ |url-status=dead |archive-url=https://web.archive.org/web/20060929185156/http://www.spc.ncep.noaa.gov/faq/tornado/ |archive-date=2006-09-29 |access-date=2006-09-08 |work=[[National Weather Service]] |publisher=[[National Oceanic and Atmospheric Administration]]}}</ref>