Miyake events: a review of the state-of-the-art

Abstract

Miyake events are fast and significant radiocarbon rises in the Earth's atmosphere. Japanese researchers from Nagoya University discovered this kind of event based on radiocarbon analysis in tree rings. They found a spike in the radioactive carbon isotope in the ring of 775AD compared to the 774AD ring. Subsequently, all such events became known by the name of the first author of the seminal paper. To date, five Miyake events have been discovered: around 12350 BC, in 7176 and 5259 BC, in 775 and 993 AD. The events of 5410 BC, 1052 and 1279 AD are less pronounced and require confirmation. Among the possible reasons for the sharp increase in the content of radiocarbon in the atmosphere a comet falling to the Earth or to the Sun, a short gamma-ray burst, a supernova outbreak were suggested. The most likely version, however, is considered to be solar energetic particles as a result of a super-powerful solar flare. Such solar events should lead to auroras in low latitudes. However, in the annals of Europe, the Middle East and the Far East, no reliable records of auroras in the years of Miyake events have been found. Nowadays, Miyake events are used in many fields of science, for example, to check the reliability of dendrochronological dating, for accurate dating of ice core layers. The most important, however, is considered to be the possibility of radiocarbon dating with an accuracy of one year.