Deep in a New Zealand swamp, scientists discovered an ancient kauri tree that had been entombed for more than 40,000 years—its trunk preserved like a wooden time capsule. But this wasn’t just any prehistoric tree. Its rings revealed something extraordinary: it had lived through the Laschamp Excursion, a rare moment when Earth’s magnetic poles reversed. More alarming, however, was the period just before the flip—known as the Adams Event—when the planet’s magnetic field all but vanished, exposing the Earth to an onslaught of cosmic radiation.

With Earth’s magnetic shield weakened to as little as 0–6% of its normal strength, solar and cosmic radiation surged in, triggering global climate chaos. Ice sheets expanded dramatically, storm systems rerouted, and once-verdant lands like parts of Australia were swallowed by desert. Some researchers believe the event contributed to the extinction of the Neanderthals and forced early humans into caves for protection—where they began creating the earliest known symbolic art. These dramatic shifts suggest the Adams Event wasn’t just a magnetic anomaly—it was a turning point in human history.

Now, the ancient kauri stands as both relic and warning. Its rings carry the silent testimony of a world on the edge, a reminder that our magnetic field is not permanent. If such a collapse were to happen today, the consequences could be dire—satellite failure, communication breakdowns, grid collapses, and rapid shifts in climate. This tree, long dead, still speaks—whispering across the ages about the fragility of the invisible forces that shield our modern world.

@didgebaba

New Zealand's Minister of Defence and Space, and ardent AI proselytiser Judith Collins is still a terrible human though.
Her husband's company has been digging these trees up and sending them off to China real quick and real cheap for ages.

#DirtyPoliticsNZ

@zl2tod what is done with them in China?

@didgebaba

Expensive furniture IIRC.

@zl2tod insane

@didgebaba

A while back someone driving a digger around the corner from the swamp kauri yard hit the very cleary signposted pipeline which runs from New Zealand's now defunct oil refinery to Auckland, and cut off the supply of avgas.

Chaos ensued.

There was no accountability,

https://www.nzherald.co.nz/nz/auckland-jet-fuel-crisis-digger-blow-ruptured-pipe-exposed-infrastructure-vulnerability/TCSQINCN3MX6LSEJM4TRADGVLM/

Auckland jet fuel crisis: Digger blow ruptured pipe, exposed infrastructure vulnerability

Govt report finds investment needed now to safeguard airport fuel supply.

NZ Herald
@didgebaba
I think this is detail about that kauri tree. Incredible story. Thanks for sharing! https://www.biographic.com/swamp-sentinels/
@stevewfolds
Swamp Sentinels - bioGraphic

Buried in mud for millennia, some of New Zealand's ancient kauri trees are revealing surprising clues about Earth's climate—past, present, and future.

bioGraphic

@RunRichRun @didgebaba Visited the largest living Kauri tree in ‘86. It may be 4,000 years old.

https://en.wikipedia.org/wiki/Te_Matua_Ngahere

Te Matua Ngahere - Wikipedia

@meli_melo ça laisse rĂȘveur

« It feels and smells as if it could have toppled a year ago. Yet when this tree last stood up-right and felt the sunlight on its leaves, Neanderthals and Denisovans still walked the Earth. Homo sapiens—still many millennia away from reaching New Zealand—had only recently colonized Europe and begun to make art. Â»

@whilelm C'est vertigineux ouais

@didgebaba I wonder how the ionosphere looks like during such an event, and how HF communication and propagation would work. I suppose geomagnetic storms will be more severe, and K indices' severity will go down a notch or two.

Well I mean, except the small chance that humans will also be extinct.

@yo3gnd @didgebaba well, does say caves saved the day last time.

Nearly so many people live in Chinese caves as across all of Canada. They'll probably survive I guess.

@didgebaba Looks like Earth could use one of these, but we fucked up on Climate Change, we'll fuck up building one of these if the magnetosphere is going.

https://www.sciencedirect.com/science/article/abs/pii/S0094576521005099

How to create an artificial magnetosphere for Mars

If humanity is ever to consider substantial, long-term colonization of Mars, the resources needed are going to be extensive. For a long-term human pre


@didgebaba These are the ruins of the SDF Macross, except we're the giants.
@didgebaba
Interesting story but these findings about field reversal don't seem to be supported by other evidence we have from around the planet at about that same time
https://www.science.org/content/article/ancient-kauri-trees-capture-last-collapse-earth-s-magnetic-field
Ancient kauri trees capture last collapse of Earth's magnetic field

Unleashed cosmic ray bombardment may have eaten up ozone, driving short-term climate swings

@RnDanger how are such events measured in the organic materials from the time? Are radiocarbon levels sufficient?

As your post says, "this and several other pieces of wood chart a surge in radiation from space, as Earth's protective magnetic field weakened and its poles flipped, a team of scientists reports today in Science."?

@didgebaba
"With Earth’s magnetic shield weakened to as little as 0–6% of its normal strength, solar and cosmic radiation surged in,"
The increased levels of carbon 14 seen in this tree from 40,000 years ago don't appear in other places, so either this tree is special or it was measured wrong.

The disclaimer in the article about the lead scientist abusing his students doesn't help me lend any benefit of doubt here

@RnDanger "They found evidence that the magnetic poles had shifted towards the equator and that the field strength had weakened to just 10 per cent of today’s levels."

https://www.newscientist.com/article/2476982-ancient-humans-may-have-faced-radiation-risk-41000-years-ago/

Ancient humans may have faced radiation risk 41,000 years ago

A weakening of Earth’s magnetic field known as the Laschamps event would have increased the threat of solar radiation, perhaps requiring ancient humans to invent protective measures

New Scientist
@didgebaba
I am having a hard time tracing their claims but i think they are using that same tree as their evidence for this

@didgebaba @futurebird

The effects of geomagnetic field minima like the Laschamp event are frequently exaggerated.

There was roughly a two-fold change in cosmic ray flux as measured by Be-10 and a smaller change in the amount of C-14 produced.

Some recent discussions: https://www.sciencedirect.com/science/article/abs/pii/S0277379124004943 , https://www.sciencedirect.com/science/article/abs/pii/S0012821X19302912 .

The temperature drop during the event was ~0.6 C, compared to -6 C for the baseline for the Last Glacial Maximum.

Beryllium ten production and relative paleointensity for the past 1.2 million years

Composite curves of relative paleointensity document the evolution of the geomagnetic field intensity during the past 1.2 Million years. Several recor


@didgebaba @futurebird

If such an event happened now it would play out over hundreds of years - giving time to react. And even current satellites, radios, and power grids would keep working.

I make this point because I keep having to explain that solar flares do not have the consequences they are often imagined to have either.

@michael_w_busch @didgebaba @futurebird What about a huge solar flare like in the 19th century? 1860s or so.

@wackJackle @didgebaba @futurebird

Things like the 1859 Carrington Event and the per-millennium Miyake Events ( https://en.wikipedia.org/wiki/Miyake_event ) can induce large current spikes in long segments of conductive material, like telegraph cables and power lines.

Surge protection systems in most countries are designed to limit the effects to only brief power outages (e.g. 1 hour in Sweden from the 2003 October flares; grid restrictions but no total outrage in New Zealand from the 2024 May flares).

Miyake event - Wikipedia

@michael_w_busch @didgebaba @futurebird Okay, so the 'normal' big flares are no big problem but a Miyake Event in modern times could have servere impacts!?

@wackJackle @didgebaba @futurebird

Even a Miyake Event would not have severe impacts on the ground or for many satellites.

The Starlinks might have problems, but that is because SpaceX cuts corners on radiation hardening.

@michael_w_busch @didgebaba @futurebird Ah, okay, thanks for the information. I thought that it would be more servere, because I've read some alarming articles a few years back. Good to know. One thing less to worry about.

@didgebaba

and if we thought the sun was uncomfortably hot before...
the risk of blindness would force us to live underground and become nocturnal.

@didgebaba Thanks for the timely truth tale, a beautiful piece of writing. Posting for all my science- and poetry-inclined friends.
@didgebaba "Deep in a New Zealand swamp," based on the photos there's not much of a swamp left. :(

@cetan @didgebaba

Well 90% of wetlands here have been lost here, so about right I guess.

@didgebaba
key point...
" it had lived through the Laschamp Excursion"

I wonder what else survived and what perished?

@didgebaba
Wow, let's hope it doesn't happen again in the near future.
@didgebaba in the first image it looks eerily like the Derelict of Alien...

@didgebaba weird fact: it's been named The Adams Event after Douglas Adams, the writer. This is because it's been dated to about 42,000 years ago.

https://en.wikipedia.org/wiki/Laschamp_event

Laschamp event - Wikipedia

@didgebaba

This is a marvelous post. Thankyou for sharing.
@didgebaba *** and were due for one.
@didgebaba "Dinosaurs are the ultimate icon for an evolutionary fact which we generally ignore, and definitely find uncomfortable to think about: nearly all species that have ever existed are extinct." - Terry Pratchett, Ian Stewart & Jack Cohen; The Science of Discworld
@didgebaba definitely the most interesting thing I've read today.