The Universe Today article "How Wood Records the Sun's Most Violent Outbursts" (by Mark Thompson, link below) discusses how how tree rings act as ancient hard drives for the Sun's biggest tantrums — specifically Miyake events. These are extreme solar proton events (or bursts of high-energy particles) that slam Earth's atmosphere, spiking production of radioactive carbon-14 (^14C). Trees suck up that extra ^14C during photosynthesis and lock it into their annual growth rings, creating detectable spikes that survive for millennia.
The piece spotlights recent research (led by Amy Hessl from West Virginia University, with Mariah Carbone and Andrew Richardson from Northern Arizona University) explaining why these signals aren't always clean or instant: Trees don't just grab atmospheric carbon on demand. They store carbs for months or even years before building new wood. Conifers like pines might use last-season reserves in spring growth, smearing a sharp atmospheric spike across multiple rings. Species, climate, and growing-season timing all mess with fidelity — harsh environments mean more storage for tough times, diluting signals. It's not a perfect timestamp; biology introduces lag and blur.
Key historical Miyake events flagged: The famous 774–775 CE spike (first discovered by Fusa Miyake in Japanese cedars), another in 993 CE (most recent confirmed), and others stretching back to prehistoric times (e.g., ~14,300 years ago, one of the largest). These are preserved globally in tree rings, cross-checked with ice-core beryllium-10 and chlorine-36.
The real hook — and why the article says forget obsessing over Carrington events — is scale. The 1859 Carrington Event was brutal: auroras to the tropics, telegraph fires, the strongest directly observed geomagnetic storm. But in ^14C terms? Barely a blip — less than 1% increase, subtle even in modern re-analyses. Miyake events? 10–20× (or more) stronger in particle flux, with ^14C jumps of several percent in a year or two. The 774 CE one was at least 5–10× Carrington; the 14,300-year-old monster was roughly double that of known recent Miyakes. If Carrington hit today, we'd face grid blackouts, satellite fry, trillions in damage. A Miyake-scale hit? Catastrophic on steroids: widespread transformer failures, months-to-years outages, lethal radiation doses for astronauts/high-altitude flights, fried electronics everywhere. Our tech-dependent civilisation is way more fragile than 1859's telegraphs.
Frequency? From ~15,000 years of records, roughly 6–9 confirmed Miyake events, suggesting one every ~1,000–2,400 years (some estimates 400–2,400). Irregular, no clear solar-cycle tie, possibly sequences of eruptions rather than single monsters.
This is peak cosmic humility. We've been patting ourselves on the back for surviving Carrington analogues in models, but tree rings whisper: The Sun's capable of far nastier surprises, and we've only had ~170 years of direct observation — blink-of-an-eye stuff. Miyakes aren't "if" but "when," and our grid/satellites/GPS/everything-electronic infrastructure has zero hardening against that level of particle barrage. It's like building cities on a fault line and ignoring quakes bigger than 1906 San Francisco because we haven't seen one lately.
The good news? These events give us precise dating anchors for archaeology (Vikings, ancient Egypt timelines get sharpened). The bad? Space weather forecasting is still primitive; we'd get maybe hours-days warning for a CME component, but particle floods could be sudden. Mitigation means better shielding, hardened transformers, diversified sats, maybe underground backups for critical stuff. The universe doesn't care about our deadlines.
https://www.universetoday.com/articles/how-wood-records-the-suns-most-violent-outbursts