While the Earth's magnetic axis is shifting somewhat, Earth's rotational axis shifts only a little bit, mostly in response to the mass redistribution of water around the Earth from land-based ice sheet losses. This is a normal response.
The net change in the position of the Earth's rotational axis is about 37 feet. The largest annual change is about 7 inches.
If you move over 37 feet, the climate doesn't change. It changes even less per year if you only move 7 inches.
https://www.jpl.nasa.gov/news/news.php?feature=6332&fbclid=IwAR30M6zx7MmHOFFnFRw8Lygr0WFv2TvbSZWKesUzxXFQ96MMZLdsLYbhSTc
The research paper itself is here:
https://advances.sciencemag.org/content/2/4/e1501693
The net change in the position of the Earth's rotational axis is about 37 feet. The largest annual change is about 7 inches.
If you move over 37 feet, the climate doesn't change. It changes even less per year if you only move 7 inches.
https://www.jpl.nasa.gov/news/news.php?feature=6332&fbclid=IwAR30M6zx7MmHOFFnFRw8Lygr0WFv2TvbSZWKesUzxXFQ96MMZLdsLYbhSTc
The research paper itself is here:
https://advances.sciencemag.org/content/2/4/e1501693
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While the Earth's magnetic field is weakening a bit and its magnetic axis is shifting somewhat, magnetic field polarity changes have no effects on climate on the timescale of human lifetimes because air isn’t ferrous. The effects on hand-held compasses are insignificant. For purposes of electronic navigation, changes in the position of the magnetic poles are constantly updated in navigational databases.
https://www.ncei.noaa.gov/news/tracking-changes-earth-magnetic-poles?fbclid=IwAR2a0pL9QVM81OF5yQpi5ljijpAiwVJ9BEYtnoi_S7obuW93fKm3tQJDEJw
https://www.ncei.noaa.gov/news/world-magnetic-model-out-cycle-release?fbclid=IwAR01FyhG-vozqBCwcN1IDfk5QUfd_1ygN3fOsRrvUn97_JMVSpgZAi6aXIQ
https://www.ncei.noaa.gov/news/world-magnetic-model-out-cycle-release?fbclid=IwAR01FyhG-vozqBCwcN1IDfk5QUfd_1ygN3fOsRrvUn97_JMVSpgZAi6aXIQ
https://www.ngdc.noaa.gov/geomag/faqgeom.shtml?fbclid=IwAR3hVbT8Z7hMNplhds-w-4VhUppqyyMBClWKkx6Lyzf6T8Ypiz7XbX00h-s
https://www.maritime-executive.com/article/position-of-magnetic-north-pole-officially-changed?fbclid=IwAR0KcNdgM1spcXnw6XHjpW3lRKcUzeNQ9kryLYREhOBgRXd4zuoFy-D9dJU
"The last time that Earth's poles flipped in a major reversal was about 780,000 years ago, in what scientists call the Brunhes-Matuyama reversal. The fossil record shows no drastic changes in plant or animal life. Deep ocean sediment cores from this period also indicate no changes in glacial activity, based on the amount of oxygen isotopes in the cores. This is also proof that a polarity reversal would not affect the rotation axis of Earth, as the planet's rotation axis tilt has a significant effect on climate and glaciation and any change would be evident in the glacial record."
And
"The science shows that magnetic pole reversal is – in terms of geologic time scales – a common occurrence that happens gradually over millennia. While the conditions that cause polarity reversals are not entirely predictable – the north pole's movement could subtly change direction, for instance – there is nothing in the millions of years of geologic record to suggest that any of the 2012 doomsday scenarios connected to a pole reversal should be taken seriously."
https://www.nasa.gov/topics/earth/features/2012-poleReversal.html?fbclid=IwAR2LY7WFUdQBTLnXw8hHjW1sKhf8nfg85tMXR4rqWXYwkmS6pzsMI0M1i64
https://www.livescience.com/18426-earth-magnetic-poles-flip.html?fbclid=IwAR0VuwKQLND8aI5hVA06DEibprJ-r6RdZ8hFjJVe2wIoenhfBY2YbIg0Cg4
"What would happen if the magnetic field of the Earth suddenly changed?
If the magnetic field of the Earth suddenly changed, and this DOES happen naturally every 250,000 years or so, the consequences would be fascinating. For life, we can see from the fossil record that the past field changes had no significant effect on living organisms. This is most curious because the field reversal ( North magnetic pole shifting to antarctica and the South magnetic pole shifting to the arctic region in the Northern Hemisphere) one might expect the field to go to zero strength for a century or so. This would let cosmic rays freely penetrate to the Earth's surface and cause mutations. This seems not to have had much effect in the past, so we probably don't really know what is going on during these field reversals. There have been a dozen of them over the last few million years, documented in the rock which has emerged and solidified along the mid-Atlantic Ridge where continental plates are slowly separating. These epochs form parallel bands all long the ridge where the rock has stored a fossilized image of the local orientation of the Earth's magnetic field for the last few million years.
Magnetic field wandering would let the aurora borealis occur at any latitude, but other than that there would be no noticeable effects other than changes in the amount of cosmic rays that penetrate to the ground. Even this effect is minimal because we can visit the Arctic and Antarctic and only receive a slight increase in cosmic rays. So long as the strength of the field remains high during this field wandering event, the effects should be pretty benign.
(-technical, non-climate discussion-)
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