北领地一位政府官员曾提议抽取地下水可能有助于稳定地球自转，防止地极反转。对此，古地磁学专家澄清了这一观点中存在的科学误区1。
专家指出，地球存在地理北极和磁北极两种不同的概念，其中地理极翻转在实际上不可能发生1。虽然磁极反转在地球历史上确实发生过，但这一过程与地表人类活动（如抽取地下水）无关1。磁极反转的发生机制源自距地表2,890至5,150公里的外核液态铁流动1。从1993年到2010年间，全球抽取的地下水使地理极每年偏移约4厘米1，但这种局部偏移与磁极反转的深层物理过程毫无关联。
根据地质记录，最后一次完整的磁极反转发生在大约780,000年前1，最近一次重大扰动是约41,000年前的拉尚普事件1。高分辨率沉积物记录表明，磁场反转过程需要数千年才能完成，全球平均耗时约7,000年1。一些科学家认为下一次反转可能在1,000至2,000年内发生1，而目前南大西洋存在称为南大西洋异常的弱磁场区域1。
A Northern Territory government official has proposed that extracting groundwater might help stabilize Earth's rotation and prevent polar reversal. However, a paleomagnetist has clarified the scientific distinctions and mechanisms at work.1
The expert explains that Earth has two distinct pole concepts: the geographic North Pole and the magnetic North Pole.1 A geographic pole reversal is effectively impossible in practical terms, whereas magnetic pole reversals, though they have occurred throughout history, are unrelated to surface activities such as water pumping.1 The mechanism behind magnetic reversals originates in the outer core's liquid iron circulation, located 2,890 to 5,150 kilometers below Earth's surface.1
Between 1993 and 2010, global groundwater extraction caused the geographic pole to shift approximately 4 centimeters annually.1 The most recent complete magnetic pole reversal occurred roughly 780,000 years ago, with the most significant recent disturbance being the Laschamp excursion about 41,000 years ago.1 High-resolution sediment records indicate that magnetic field reversals require thousands of years to complete, averaging around 7,000 years globally.1 Some scientists suggest the next reversal could occur within 1,000 to 2,000 years, and a region of weakened magnetic field known as the South Atlantic Anomaly currently exists in the South Atlantic.1
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