Editing Lightning (section)

=== Environmental changes ===
More permanent or longer-lasting environmental changes include the following.

==== Atmospheric chemistry ====
The very high temperatures generated by lightning lead to significant local increases in [[ozone]] and [[Nitrogen oxide|oxides of nitrogen]]. Each lightning flash in temperate and sub-tropical areas produces 7&nbsp;kg of {{NOx}} on average.<ref>{{cite magazine|url=https://www.sciencedaily.com/releases/2009/10/091030100022.htm|title=Lightning's 'NOx-ious' Impact On Pollution, Climate|magazine= Science News|access-date=August 4, 2018}}</ref> In the [[troposphere]] the effect of lightning can increase {{NOx}} by 90% and ozone by 30%.<ref>{{cite web|url=https://www.nasa.gov/centers/goddard/news/topstory/2003/0312pollution.html|publisher=NASA|title=Surprise! Lightning has big effect on atmospheric chemistry|access-date=August 4, 2018|archive-date=March 9, 2019|archive-url=https://web.archive.org/web/20190309075516/https://www.nasa.gov/centers/goddard/news/topstory/2003/0312pollution.html|url-status=dead}}</ref>

==== Ground fertilisation ====
Lightning serves an important role in the [[nitrogen cycle]] by oxidizing diatomic nitrogen in the air into [[nitrates]] which are deposited by rain and can fertilize the growth of plants and other organisms.<ref>{{cite journal | last1 = Bond | first1 = D.W. | last2 = Steiger | first2 = S. | last3 = Zhang | first3 = R. | last4 = Tie | first4 = X. | last5 = Orville | first5 = R.E. | year = 2002 | title = The importance of NOx production by lightning in the tropics | journal = Atmospheric Environment | volume = 36 | issue = 9| pages = 1509–1519 | doi=10.1016/s1352-2310(01)00553-2| bibcode = 2002AtmEn..36.1509B }}</ref><ref>Pickering, K.E., Bucsela, E., Allen, D, Cummings, K., Li, Y., MacGorman, D., Bruning, E. 2014. Estimates of Lightning NOx Production Per Flash from OMI NO2 and Lightning Observations. XV International Conference on Atmospheric Electricity, 15–20, June 2014.</ref>

==== Induced permanent magnetism ====
The movement of electrical charges produces a magnetic field (see [[electromagnetism]]). The intense currents of a lightning discharge create a fleeting but very strong magnetic field. Where the lightning current path passes through rock, soil, or metal these materials can become permanently magnetized. This effect is known as lightning-induced [[Remanence|remanent]] magnetism, or LIRM. These currents follow the least resistive path, often horizontally near the surface<ref>{{cite journal|title=The Re-magnetization of a Surface Outcrop by Lightning Currents|doi=10.1111/j.1365-246X.1961.tb02963.x|date=1961|last1=Graham|first1=K.W.T.|journal=[[Geophysical Journal International]]|volume=6|issue=1|page=85|bibcode = 1961GeoJ....6...85G |doi-access=free}}</ref><ref>Cox A. (1961). [http://pubs.usgs.gov/bul/1083e/report.pdf Anomalous Remanent Magnetization of Basalt] {{webarchive|url=https://web.archive.org/web/20130529011301/http://pubs.usgs.gov/bul/1083e/report.pdf |date=May 29, 2013 }}. U.S. Geological Survey Bulletin 1038-E, pp. 131–160.</ref> but sometimes vertically, where faults, ore bodies, or ground water offers a less resistive path.<ref>Bevan B. (1995). [https://www.researchgate.net/profile/Bruce-Bevan/publication/318826400_Magnetic_surveys_and_lightning/links/59807da84585156238facc4d/Magnetic-surveys-and-lightning.pdf "Magnetic Surveys and Lightning"]. ''Near Surface Views'' (newsletter of the Near Surface Geophysics section of the Society of Exploration Geophysics). October 1995, pp. 7–8.</ref> One theory suggests that [[lodestone]]s, natural magnets encountered in ancient times, were created in this manner.<ref>{{cite journal |doi=10.1029/1999GL900496 |first=Peter |last=Wasilewski |author2=Günther Kletetschka |title=Lodestone: Nature's only permanent magnet – What it is and how it gets charged |url=http://lep694.gsfc.nasa.gov/gunther/gunther/Wasilewski1999.pdf |archive-url=https://web.archive.org/web/20061003193325/http://lep694.gsfc.nasa.gov/gunther/gunther/Wasilewski1999.pdf |archive-date=October 3, 2006 |journal=[[Geophysical Research Letters]] |volume=26 |issue=15 |pages=2275–78 |date=1999 |access-date=July 13, 2009| url-status=dead |bibcode = 1999GeoRL..26.2275W | s2cid=128699936}}</ref>

Lightning-induced magnetic anomalies can be mapped in the ground,<ref>{{Cite journal |last1=Sakai |first1=H. S. |last2=Sunada |first2=S. |last3=Sakurano |first3=H. |date=1998 |title=Study of Lightning Current by Remanent Magnetization |journal=Electrical Engineering in Japan |volume=123 |issue=4 |pages=41–47 |doi=10.1002/(SICI)1520-6416(199806)123:4<41::AID-EEJ6>3.0.CO;2-O}}</ref><ref>[http://www.archaeophysics.com/pubs/LIRM.html Archaeo-Physics, LLC | Lightning-induced magnetic anomalies on archaeological sites] {{webarchive|url=https://web.archive.org/web/20071012080847/http://www.archaeophysics.com/pubs/LIRM.html |date=October 12, 2007 }}. Archaeophysics.com. Retrieved on June 23, 2012.</ref> and analysis of magnetized materials can confirm lightning was the source of the magnetization<ref>{{Cite journal |last=Maki |first=David |date=2005 |title=Lightning strikes and prehistoric ovens: Determining the source of magnetic anomalies using techniques of environmental magnetism |journal=Geoarchaeology |volume=20 |issue=5 |pages=449–459 |doi=10.1002/gea.20059 |bibcode=2005Gearc..20..449M |url=http://www.archaeophysics.com/pubs/lightning-oven.pdf |url-status=dead |archive-url=https://web.archive.org/web/20130515025335/http://www.archaeophysics.com/pubs/lightning-oven.pdf |archive-date=May 15, 2013  |citeseerx=10.1.1.536.5980 |s2cid=52383921 |access-date=November 1, 2017 }}</ref> and provide an estimate of the peak current of the lightning discharge.<ref>{{Cite journal |last1=Verrier |first1=V. |last2=Rochette |first2=P. |date=2002 |title=Estimating Peak Currents at Ground Lightning Impacts Using Remanent Magnetization |journal=[[Geophysical Research Letters]] |volume=29 |issue=18 |page=1867 |doi=10.1029/2002GL015207|bibcode = 2002GeoRL..29.1867V |s2cid=128577288 |doi-access=free }}</ref>