Tree rings document mega radiation storms

Could we be in store for a gigantic and potentially dangerous blast of cosmic radiation? Possibly, according to a new study published Oct. 26 in Proceedings of the Royal Society A: Mathematical and Physical Sciences. Enormous bursts of radiation, known as Miyake events after the Japanese scientist who first discovered them,strike the Earth roughly every 1,000 years. The last one occurred in A.D. 993.

Researchers at the University of Queensland, Australia, are studying the growth rings of trees thousands of years old using new software they have developed to learn more about Miyake events. The sudden surge of radiation during one of the events transforms part of Earth’s atmospheric nitrogen into carbon, which trees absorb. The excess carbon leaves a telltale record behind in the tree’s growth rings.

Scientists have long thought these mysterious and unpredictable phenomena originate from huge solar flares, but the new study casts doubt on that assumption and leaves experts scratching their heads. The study shows the events do not correlate with sunspot activity. Solar flares involve a single explosion, but Miyake events can last one to two years or more.

One event in 663 B.C. lasted up to three years, and another in 5,480 B.C. built up across a decade, astrophysicist Benjamin Pope, one of the researchers, told ABC News. Further, stars like our sun are not known to produce solar flares strong enough to cause a Miyake event.

“There are six known [Miyake] events spanning nearly 10,000 years,” Pope said. They are “a kind of extreme astrophysical phenomenon that we don’t understand, and it actually could be a threat to us.”

Scientists estimate there is only a 1 percent chance that another Miyake event will happen in the next decade. But such an occurrence would cause chaos, the scientists warned. The blast of geomagnetic energy can disrupt electrical currents and damage electronics. The largest solar storm ever recorded was the 1859 Carrington event, which released roughly the same energy as 10 billion 1-megaton atomic bombs and destroyed telegraph systems all over the world.

If an equally powerful flare hit Earth now, it would cause an “internet apocalypse,” blackouts, and trillions of dollars in damages, Live Science reported. But a Miyake event that occurred in A.D. 774 was 80 times stronger than the Carrington event. If such a radiation burst occurred today it would destroy technologies like satellites, internet cables, long-distance power lines, and transformers around the world.

“The effect on global infrastructure would be unimaginable,” Pope said in a statement.