[[Picha:Geodynamo_Between_Reversals.gif|thumb|Uga sumaku wa Dunia katika uigaji wa kompyuta. Mistari inaonyesha mistari ya uga sumaku, ya buluu pale ambako uga sumaku unaelekea kitovu cha Dunia, njano pale ambako inaelekea mbali na kitovu. Mistari mingi ya karibu iko kwenye kiini cha Dunia]]
'''Uga sumaku wa Dunia''' ''(kwa [[Kiingereza]]: geomagnetic field, Earth's magnetic field)'' ni [[uga sumaku]] ambayoambao inazungukaunazunguka [[Dunia]]. InaeneaUnaenea kuanzia [[kiini cha Dunia]] hadi [[anga-nje]] inapoathirianaunapoathiriana na [[upepo wa Jua]] (mkondo wa vyembe vyenye chaji kutoka Jua). Ugasumaku yawa Dunia inakingaunakinga [[uhai]] [[duniani]] dhidi ya [[mnururisho]] haribifu kutoka anga-nje
Uga sumaku yawa Dunia inaundwaunaundwa na mzunguko wa Dunia; mzunguko huo unasababisha [[Mkondo wa umeme|mikondo ya umeme]] kutokea kwenye [[kiini]] cha Dunia ambako [[joto]] la ndani linatoka nje.<ref name="T.I">{{Cite journal|last=Zvereva T.I.|date=2012|title=Motion of the Earth's magnetic poles in the last decade|journal=Geomagnetism and Aeronomy|volume=52|issue=2|pages=278-286|access-date=3 February 2013}}</ref> Uga sumaku hiyohuo si yawa kudumu ikijulikanaukijulikana imeshabadilikaumeshabadilika mara kadhaa katika [[historia]] ya Dunia.<ref name="v">{{Cite journal|last=Dergachev V.A. et al.|date=2012|title=Impact of the geomagnetic field and solar radiation on climate change|journal=Geomagnetism and Aeronomy|volume=52|issue=8|pages=959-976|access-date=3 February 2013}}</ref>
Uga sumaku yawa Dunia huwa na [[ncha]] sumaku zinazopatikana karibu na [[Ncha za kijiografia|ncha za kijiografia za Dunia]]. Ncha sumaku huhama mara kwa mara; kwenye [[mwaka]] [[2007]] ncha sumaku ya [[kaskazini]] ilikuwa na [[umbali]] wa [[km]] 960 kutoka ncha ya kijiografia ikiendelea kuhama takriban kilomita 50 kila mwaka<ref name="newitt2007">L. R. Newitt, A. Chulliat, and J.-J. Orgeval, [http://www.terrapub.co.jp/journals/EPS/pdf/2009/6106/61060703.pdf Location of the North Magnetic Pole in April 2007], Earth Planets Space, 61, 703–710, 2009</ref>. [[Dira]] hutumia uga sumaku huo kudokeza nchani, lakini ilhali kuna tofauti kati ya ncha sumaku ya kaskazini na [[Ncha ya kaskazini|ncha ya kijiografia ya kaskazini]] ni lazima kujua tofauti hiyo kwa mwongozo wa [[safari]] za [[meli]] au [[Ndege (uanahewa)|ndege]].
==Kinga ya uhai==
Uga sumaku yawa Dunia inakengeushaunakengeusha [[upepo wa Jua]] ambao ni mkondo vya vyembe kutoka Jua. Kama upepo wa Jua ungeweza kupiga [[angahewa]] moja kwa moja ungeondoa [[tabaka la ozoni]] linalozuia [[Urujuanimno|mnururisho haribifu wa urujuanimno]] kufika kwenye uso wa ardhi<ref>{{cite journal |title=Solar wind hammers the ozone layer |first=Quirin |last=Shlermeler |date=3 March 2005 |doi=10.1038/news050228-12 |journal=News@nature |url=http://www.nature.com/news/2005/050228/full/news050228-12.html}}</ref>. [[Utafiti]] wa [[Mirihi|sayari ya Mirihi]] umeonyesha kwamba kupotea kwa uga sumaku yawa [[sayari]] hiyo kulisababisha kupotea kwa [[gesi]] karibu zote za angahewa ya Mirihi<ref>{{cite news |title=Solar wind ripping chunks off Mars |url=http://archive.cosmosmagazine.com/news/solar-wind-ripping-chunks-mars/ |work=Cosmos Online |date=25 November 2008 |accessdate=21 October 2013 |url-status=dead |archiveurl=https://web.archive.org/web/20160304072916/http://archive.cosmosmagazine.com/news/solar-wind-ripping-chunks-mars/ |archivedate=4 March 2016 }}</ref>.
Duniani uga sumaku wake unashika vyembe hivihivyo katika eneo la [[Ukanda wa Van Allen|ukanda wa Van Allen]] ambako vinazunguka sayari yetu kwa kimo[[umbali]] chawa kilomita 700 au zaidi bila kupiga uso wa Dunia.
