{"id":838134,"date":"2026-08-01T16:43:15","date_gmt":"2026-08-01T16:43:15","guid":{"rendered":"https:\/\/www.newsbeep.com\/au\/838134\/"},"modified":"2026-08-01T16:43:15","modified_gmt":"2026-08-01T16:43:15","slug":"can-pumping-groundwater-really-flip-earths-poles-an-expert-explains","status":"publish","type":"post","link":"https:\/\/www.newsbeep.com\/au\/838134\/","title":{"rendered":"Can pumping groundwater really flip Earth\u2019s poles? An expert explains"},"content":{"rendered":"<p>Last week a government minister in the Northern Territory, spruiking a plan to make Darwin \u201cthe datacentre capital of the globe\u201d, suggested it might be a good idea to <a href=\"https:\/\/www.theguardian.com\/australia-news\/2026\/jul\/23\/australia-politician-claims-northern-territory-water-could-flip-earths-magnetic-poles\" rel=\"nofollow noopener\" target=\"_blank\">pump out groundwater to keep Earth\u2019s spin steady<\/a>. If we don\u2019t, she said, we might risk \u201cflipping the poles again\u201d.<\/p>\n<p>Is she right? And what\u2019s she even talking about?<\/p>\n<p>As a palaeomagnetist \u2013 someone who studies Earth\u2019s magnetic field and reads ancient rocks to understand how it was in the past \u2013 let me walk you through what it means for Earth\u2019s poles to flip, what groundwater has to do with it, and why there is absolutely nothing to worry about.<\/p>\n<p>Which pole, exactly?<\/p>\n<p>The first problem is that there are two very different \u201cnorth poles\u201d.<\/p>\n<p>The geographic North Pole is the one on every map, and it is the spot where Earth\u2019s spin axis meets the surface. This pole drifts by about 10cm a year, as ice, water and movements of Earth\u2019s crust shift mass around the planet. <\/p>\n<p>The magnetic north pole is something else entirely: the spot where the magnetic field points straight down. It slowly wanders around the geographic pole, a restlessness we call secular variation.<\/p>\n<p>The unflippable geographic pole<\/p>\n<p>Can the geographic pole flip? In practice, no. <\/p>\n<p>A spinning Earth behaves like a gyroscope \u2013 a spinning top that resists being tipped over. Its axis stays remarkably steady, drifting only very slowly. A sudden flip, with the spin axis tipping right over, is essentially impossible and unknown in Earth\u2019s history.<\/p>\n<p>Scientists once thought evidence of glaciers near the equator, between around 700 million and 635 million years ago, may have been evidence of an ancient drastic move or <a href=\"https:\/\/doi.org\/10.1038\/24845\" rel=\"nofollow noopener\" target=\"_blank\">flip in the geographic pole<\/a>.<\/p>\n<p>But that explanation has largely fallen away. Most researchers now believe the glaciers occurred during a \u201cSnowball Earth\u201d period, when the world was frozen <a href=\"https:\/\/doi.org\/10.1126\/science.281.5381.1342\" rel=\"nofollow noopener\" target=\"_blank\">almost all the way to the tropics<\/a>.<\/p>\n<p>As for pumping groundwater, it can affect the geographic pole \u2013 but only very slightly. From 1993 to 2010, all the groundwater pumped worldwide shifted this pole by <a href=\"https:\/\/doi.org\/10.1029\/2023GL103509\" rel=\"nofollow noopener\" target=\"_blank\">about 4cm a year<\/a>.<\/p>\n<p>The magnetic pole is a different story<\/p>\n<p>Earth\u2019s magnetic field, by contrast, really does flip. It has happened often in the past, but at irregular and unpredictable intervals.<\/p>\n<p>The last complete reversal was about 780,000 years ago. The most recent big disturbance was the <a href=\"https:\/\/en.wikipedia.org\/wiki\/Laschamp_event\" rel=\"nofollow noopener\" target=\"_blank\">Laschamp excursion<\/a> roughly 41,000 years ago, when the field\u2019s strength collapsed almost to zero and the magnetic pole <a href=\"https:\/\/doi.org\/10.1093\/gji\/ggab276\" rel=\"nofollow noopener\" target=\"_blank\">swung down towards the equator<\/a> before recovering.<\/p>\n<p>Even then, a reversal is no overnight switch: high-resolution sediment records \u2013 including from <a href=\"https:\/\/doi.org\/10.1016\/j.quaint.2013.06.010\" rel=\"nofollow noopener\" target=\"_blank\">Armenian lake beds<\/a> \u2013 show the field weakening and swinging over thousands of years, with <a href=\"https:\/\/doi.org\/10.1038\/nature02459\" rel=\"nofollow noopener\" target=\"_blank\">a global average of around 7,000 years<\/a>. Looking at this restless history, it\u2019s fair to say another reversal is likely at some point in the geological future.<\/p>\n<p>Could it be soon? Some scientists note the field\u2019s strength has been falling steadily and argue a reversal could be only one or two thousand years away. There is currently a weak patch over the South Atlantic known as the <a href=\"https:\/\/svs.gsfc.nasa.gov\/4840\/\" rel=\"nofollow noopener\" target=\"_blank\">South Atlantic Anomaly<\/a>, which is seen as a possible starting point.<\/p>\n<p>Earth\u2019s magnetic field is generated by swirling liquid iron in the outer core. This  system is so complex no one can truly predict it, and its strength could just as easily start climbing again. And when researchers compared the South Atlantic Anomaly with the Laschamp excursion, they concluded we are probably <a href=\"https:\/\/doi.org\/10.1073\/pnas.1722110115\" rel=\"nofollow noopener\" target=\"_blank\">not on the verge of a reversal at all<\/a>.<\/p>\n<p>Made deep inside Earth<\/p>\n<p>Crucially, magnetic pole reversals are born in the liquid outer core, between 2,890km and 5,150km beneath our feet. We still don\u2019t know exactly why they happen, but we do know that structures deep in the overlying mantle shape <a href=\"https:\/\/doi.org\/10.1038\/ngeo1521\" rel=\"nofollow noopener\" target=\"_blank\">how the field behaves during reversals<\/a>. <\/p>\n<p>These structures affect <a href=\"https:\/\/doi.org\/10.1016\/j.epsl.2017.12.010\" rel=\"nofollow noopener\" target=\"_blank\">how often reversals happen and what they look like<\/a>. The South Atlantic Anomaly itself <a href=\"https:\/\/doi.org\/10.1073\/pnas.2001217117\" rel=\"nofollow noopener\" target=\"_blank\">sits above one such deep structure<\/a>.<\/p>\n<p>Even the most violent surface events don\u2019t seem to reach that far down. The giant asteroid impact linked to the extinction of the dinosaurs, for example, is not thought to have triggered a reversal. <\/p>\n<p>True polar wander<\/p>\n<p>There is one more kind of pole movement: true polar wander. Here the spin axis stays fixed in space while the whole solid Earth slowly rotates respect to it.<\/p>\n<p>This means the poles shift relative to the continents \u2013 a gradual drift of up to a few degrees per million years, driven by enormous masses shifting inside the mantle.<\/p>\n<p>In the <a href=\"https:\/\/en.wikipedia.org\/wiki\/Precambrian\" rel=\"nofollow noopener\" target=\"_blank\">Precambrian Era<\/a>, billions of years ago, polar wander probably helped drag Earth\u2019s first supercontinents towards the equator, since a spinning planet is most stable when its biggest masses sit there.<\/p>\n<p>So where does this leave us with groundwater and flipping poles? Earth really is a deeply interconnected system, and moving water around does shift the poles measurably, by centimetres a year. <\/p>\n<p>But a flip of the geographic pole is impossible, and magnetic reversals are almost certainly disconnected from anything we do at the surface. We can nudge the climate, but there is no reason to think we could reach down and flip the switch in Earth\u2019s core.<\/p>\n","protected":false},"excerpt":{"rendered":"Last week a government minister in the Northern Territory, spruiking a plan to make Darwin \u201cthe datacentre capital&hellip;\n","protected":false},"author":2,"featured_media":838135,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[22],"tags":[64,63,75,128],"class_list":["post-838134","post","type-post","status-publish","format-standard","has-post-thumbnail","category-environment","tag-au","tag-australia","tag-environment","tag-science"],"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/posts\/838134","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/comments?post=838134"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/posts\/838134\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/media\/838135"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/media?parent=838134"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/categories?post=838134"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/tags?post=838134"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}