Are you regularly watching for the next Carrington event?

Long time readers will know that I think the clickbait pushers talk about a really big solar flare / coronal mass ejection (CME) far more often than the subject deserves.  The Carrington event in 1859 was truly remarkable and if an equivalent thing were to happen now, it could do pretty substantial damage.  What that statement doesn't address, though, is that while solar flares and CMEs are common there hasn't been one that had the same effects on Earth since then (1859) despite far more reliance on distributed electricity, the power grid and so on.  As we get more susceptible, the damage from solar eruptions goes down?

There's a handful of reasons for that.  One is that the solar activity patterns have to be conducive to producing the strong flares, and solar activity has been decreasing every cycle since the strongest cycle recorded since 1750 (see bottom plot here), cycle 19 in the late 1950s.  For a graph showing as far back as the mid-1970s, see the plot I put in my regular cycle updates - the bottom plot in the last update at the end of April, for example.  You'll see that the current cycle (25) is stronger than the previous cycle but 24 was the weakest cycle in a hundred years.  It's just now close to the same levels as 23 (1996 - 2008) but has not surpassed it in any monthly measurement.

The other is that even if there is a strong flare it has to be Earth-directed.  During the peak days of cycle 23 we were getting X-class flares a few times every month, and no damage was done.  There was a super flare in November of 2003 that was genuinely scary and the kind of flare to worry about.  The biggest flare seen since the satellite age started, it was classed as X28 but only in retrospect - because it saturated the X-ray detectors on the satellites and they couldn't measure it properly.  Why didn't it harm us? Because it was on the limb of the sun and the CME went 90 degrees to our direction.  The summary is not only does this extremely strong (and rare) CME or flare need to happen, but it has to be pointed at Earth - basically perfectly centered on the sun from where we view.  

With something like the Carrington event that happened once in recorded history it's pretty futile to try to calculate the odds of the next one.  I mean, the solar cycles pretty much occur every 11 years and we have a hard time predicting exactly when they start, when they peak and other routine events like that.

It's important to know that bigger impacts than the Carrington have happened in history.  One of the first big ones I read about has been calculated to have occurred in 774 AD - and that was discovered almost accidentally when a college student from UC-SD found a record of a “red crucifix” in the skies over Britain in that year: 

 A.D. 774. This year the Northumbrians banished their king, Alred, from York at Easter-tide; and chose Ethelred, the son of Mull, for their lord, who reigned four winters. This year also appeared in the heavens a red crucifix, after sunset; the Mercians and the men of Kent fought at Otford; and wonderful serpents were seen in the land of the South-Saxons.

All of which is to setup a story of a "Carrington-like" event that was recently discovered and calculated to have occurred in 12,350 BC.  If 1859's Carrington Event was a "big, major" event, this one was a "humongous, insanely, obscenely strong" solar blast.  

More than 14 thousand years ago, there was a solar storm so big, trees still remember it. Dwarfing modern solar storms, the event would devastate technology if it happened again today. Spoiler alert: It could.

I would modify that "spoiler alert," or have deleted it altogether, but I leave it because it's a direct quote.  "Could" is irrelevant.  Does it happen once a year or once in a billion years?  I also don't like saying "trees still remember it" because trees don't have memory - they're not even still living.  These are nearly fossilized trees that have unusual amounts of carbon 14 caused by the flare/CME. 

Subfossil trees along the banks of the Drouzet river in France.

The record-strong storm is described by a paper in the upcoming July 2025 edition of the peer-reviewed journal Earth and Planetary Science Letters. It occurred in 12,350 BC and is classified as a "Miyake Event."

Miyake Events are solar storms that make the Carrington Event of 1859 look puny. Trees "remember" them in their rings, which store the carbon-14 created by gargantuan storms. At least six Miyake Events have been discovered and confirmed since Fusa Miyake found the first one in 2012. The list so far includes 664-663 BC, 774 AD, 993 AD, 5259 BC, 7176 BC, and 12,350 BC.

The Miyake Event of 12,350 BC is especially intriguing. It appears as a carbon-14 spike in Scots Pine trees along the banks of the Drouzet river in France, with a matching beryllium-10 spike in Greenland ice cores. The event was global and, based on the size of the spikes, very big.

In the effort to pinpoint exactly when this happened, the conventional ways of dating the Carbon 14 inducing event had to be revised. 

When a solar storm creates carbon-14 in the upper atmosphere, the radioisotope doesn't immediately appear in the woody flesh of trees. Getting there involves months to years of atmospheric circulation influenced by climate and geography, and even then the carbon-14 has to arrive during the tree's growing season, otherwise it won't be "taken up." High-altitude trees are favored because they encounter the carbon-14 first, while different species each have their own sensitivity. 
...
To solve this problem, Kseniia Golubenko and Ilya Usoskin from the University of Oulu in Finland developed a chemistry-climate model (SOCOL:14C-Ex) specifically for Ice Age solar storms. It takes into account ice sheet boundaries, sea levels, and geomagnetic fields that existed during the Pleistocene's Late Glacial period. Using this model, they were able to interpret tree ring data for 12,350 BC.

My "Graybeard who has been burned too many times" persona said, "how do we know this new method is any good?"  They present calculated dates that agree with those predicted the old way. 

According to their paper, 12,350 BC is the biggest Miyake Event yet. It produced a hailstorm of solar particles 500 times greater than the most intense solar particle storm recorded by modern satellites in 2005. During the 2005 event, an airline passenger flying over the poles might have received a year's worth of sea-level cosmic radiation in just one hour. During the 12350 BC event, the same dose would have been received in a mere eight seconds.

It's an interesting story and the paper is online to read.  Does this change your life?  I can say confidently the only thing it's likely to change for me is to make me more resistant to the "everything is the next Carrington event" stuff we have to live with.  If you're spending your life watching for the next Carrington event, chances are there are more productive things you can do with your time, money and life.