Earth's Last Magnetic Pole Flip Happened Much More Slowly Than Previously Thought


Any study suggests earth's magnetic poles may take far longer to flip than previously. I thought a new analysis reported in the journal science advances shows. The process may take up to twenty two thousand years to complete. That's more than twice as long as the nine thousand years. He's previously estimated this growing evidence that earth's magnetic poles are about to flip the north magnetic pole will become south and the south magnetic pole will become north last time. This happened with some seven hundred and seventy thousand years ago when it does happen. It'll be the first magnetic field polarity reversal in modern times times and that raises some serious questions about how today's technology with coq with the change to us me mortals on the surface of this revolving planet around the sun first magnetic field seemed steady and true reliable enough to navigate by your largely hidden from daily life less your pilot. The magnetic field drifts waxes awesome wayne's constantly when i'm flying one of the first things i do when i get in the cockpit of an aircraft is to readjust the cockpits compass to the latest readings for true north both for years. The magnetic north pole was wandering around pats of northern canada but more recently it's been careering towards siberia which recently forced the global positioning positioning system which underlies old model navigation updated software sooner than expected to account for the shift on average the magnetic pole shifts and reverses versus. That's polarity roughly every hundred and fifty thousand years or so that with the last one occurring some seven hundred and seventy thousand years ago with long jude for the knicks flip and there are some early signs that a possible paul reversal may be about to occur the accelerating movement of the north magnetic pole is one sign another other is something known as the south atlantic anomaly a weed pad of the south atlantic ocean between brazil and africa compass needles go nuts pointing south instead of north north and it's not just compass needles affected the south atlantic anomaly region causes earth ina van allen radiation belt to move closer to the earth surface dipping down onto just two hundred kilometers in altitude this results in an increase flocks of energetic particles in this region exposing orbiting spacecraft the high than usual levels of radiation listen effect the international space station required extra shielding just deal with this problem nashes reported that modern laptops of crushed aboard space shuttle flights as they a pass through the anomaly and the hubble space telescope doesn't do any observations while it's passing through the anomaly whether or not the south atlantic anomaly really does mean a polls colds are about the flip polarity is yet to be saying the problem is scientists have only a very limited understanding as to exactly why the film reversals occur or how they happen now new research by university of wisconsin madison geologist brad singer suggests the most recent short reversal seven hundred and seventy thousand years ago took at least twenty the two thousand years to complete that several times longer than previously thought and the results further color the question some controversial findings that some polar reversals could occur within inhuman lifetime than you analysis is based on advances in measurement capabilities at a global survey of lava flows ocean sediment at arctic ice coast rose providing a more detailed look at a turbulent time for earth's magnetic field of a millennia. The planet's magnetic food weakened partly shifted stabilized the game and then finally reversed for good to the orientation we know today. The new results provide a clearer m._o. Nuanced picture of reversals at a time when some scientists believe we may maybe experiencing the early stages of paul reversal and you other researchers dispute the very notion of a present day. Paul reversal singer says unless you have the complete accurate accurate in high resolution record of water filled reversal really's like it would be difficult to discuss the mechanics of generating one. We know that earth's magnetic field is produced by the planet's molten alton liquid metallic out of core as it spins around the solid. I and inigo generating powerful electromagnetic currents. What's coda jet dynamo this year dynamic in a creative field. That's most stable going through roughly the geographic north and south poles but the field shifts in weakened significantly during reversals. We know this because <unk> asni rocks formed typically other volcanic lava flows or a sediments being deposited on the sea floor they leave a record the magnetic field the time they were created and geologists can survey this global record piecing together. The history of magnetic fields going back millions of years. Their record is clearest for the most recent reversal that one seven hundred seventy thousand years ago for the current analysis singer and colleagues looked at lava flows from chile to haiti hawaii the caribbean and the canary islands and they collected samples from these latter flows of several field seasons lava flows are ideal records of the magnetic field they have lots of iron bearing ring minerals and as cool and solidify they lock in the direction of the planet's magnetic field the research is combined magnetic field readings and radio acid type dating samples from seven lava flow sequences to recreate the magnetic field over a span of seventy thousand years centered on las reversal they found the final reverse was quite quick by geological standards less than four thousand years but it had been preceded by an extended period of instability included excursions which are temporary partial reversals the polls stretching back another eighteen thousand years. That's more than twice as long as suggested by other studies which claimed reversals wrap up within about nine thousand years the lava flow the data was corroborated by magnetic readings from the seafloor which provided more continuous but less precise source of data than lab iraq's single and colleagues also used at arctic ice core samples apples to track the deposition of beryllium which is produced by cosmic radiation colliding with molecules in the atmosphere. You say when the magnetic reversing weakens allowing more radiation in from space to hit the atmosphere producing more beryllium since humanity began recording the strength of the earth's magnetic field. It's actually decrease in strength by about five percent century century and his records like singing shows. A weakening field seems to be a precursor to an eventual field reversal although it's far from clear that a reversal is imminent reversing planetary magnetic food would significantly affect navigation as well as satellite and terrestrial communications but if the current studies right it means society would have many generations to adapt to what would be a lengthy period of magnetic instability stewart gary. You're

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