A Single-Year Cosmic Ray Event at 5410 BCE Registered in ¹⁴C of Tree Rings

Summary, in English

The annual ¹⁴C data in tree rings is an outstanding proxy for uncovering extreme solar energetic particle (SEP) events in the past. Signatures of extreme SEP events have been reported in 774/775 CE, 992/993 CE, and ∼660 BCE. Here, we report another rapid increase of ¹⁴C concentration in tree rings from California, Switzerland, and Finland around 5410 BCE. These ¹⁴C data series show a significant increase of ∼6‰ in 5411–5410 BCE. The signature of ¹⁴C variation is very similar to the confirmed three SEP events and points to an extreme short-term flux of cosmic ray radiation into the atmosphere. The rapid ¹⁴C increase in 5411/5410 BCE rings occurred during a period of high solar activity and 60 years after a grand ¹⁴C excursion during 5481–5471 BCE. The similarity of our ¹⁴C data to previous events suggests that the origin of the 5410 BCE event is an extreme SEP event.

• Författare: F. Miyake; I. P. Panyushkina; A. J.T. Jull; F. Adolphi; N. Brehm; S. Helama; K. Kanzawa; T. Moriya; R. Muscheler; K. Nicolussi; M. Oinonen; M. Salzer; M. Takeyama; F. Tokanai; L. Wacker
• Avdelning/ar: Kvartärgeologi; MERGE: ModElling the Regional and Global Earth system; BECC: Biodiversity and Ecosystem services in a Changing Climate
• Publiceringsår: 2021-06-16
• Språk: Engelska
• Publikation/Tidskrift/Serie: Geophysical Research Letters
• Volym: 48
• Issue: 11
• Länkar: http://dx.doi.org/10.1029/2021GL093419
• Dokumenttyp: Artikel i tidskrift
• Förlag: American Geophysical Union (AGU)
• Ämne: Climate Research
• Nyckelord: cosmogenic nuclide; radiocarbon; solar activity; solar energetic particle; tree rings
• Aktiv: Published
• ISBN/ISSN/Övrigt: ISSN: 0094-8276