Radiocarbon Production by Thunderstorms

Abstract

In view of the neutron flux enhancements observed in thunderstorms, a contribution of thunderstorm neutrons to atmospheric radiocarbon (isotope 14 6 C) production is analyzed in connection with the archaeometry. Herein, estimates of neutron fluence per lightning electromagnetic pulse in regions with severe thunderstorm activity, at which a local rate of the 14 6 C production is comparable to the observed rates, are shown to be consistent with the measured magnitudes of thunderstorm neutron fluence. At present, available observations of atmospheric neutron and parent gamma ray flashes correlated with thunderstorms do not allow making final conclusions about thunderstorm contributions to 14 6 C production. For this, numerous studies of high-energy phenomena in thunderstorms are required, especially in the tropical belt where the thunderstorm activity is especially severe and where the 14 6 C production by galactic cosmic rays is almost independent of the solar activity disturbing the Earth's magnetic field shielding the Earth from cosmic rays. Plain Language Summary Decay of radiocarbon accumulated in fossil biota is widely used in archaeometry. A capture by atmospheric nitrogen nuclei of neutrons, produced by cosmic rays, is causal to the radiocarbon production. In view of that thunderstorms produce neutrons their contribution in the radiocarbon production is analyzed. In regions with severe thunderstorm activity, evaluated neutron numbers per unit area (fluence) per lightning required for a rate of the radiocarbon production by thunderstorms to be comparable to the measured rate magnitudes are consistent with the measured magnitudes of thunderstorm neutron fluence. Available data on thunderstorm neutrons and parent to them gamma ray flashes do not allow making final conclusion about the thunderstorm deposition in the radiocarbon production. For this, numerous observations are required, especially in tropics where the thunderstorm activity is extremely strong and where the radiocarbon production is almost independent of the solar activity disturbing the Earth's magnetic field shielding the Earth from cosmic rays.

Significant enhancements of secondary cosmic rays and electric field at the high mountain peak of Lomnický Štít in High Tatras during thunderstorms

“…Investigation of strong TGEs accompanied by photonuclear reactions might also find practical applications as the majority of neutrons produced in atmosphere disappear via neutron capture reaction 14 N + n → 14 C + p, where p denotes a proton. The resulting isotope 14 C is quasi-stable with a half-life of 5730 years and is frequently used in radiocarbon dating (Babich and Roussel-Dupré 2007;Enoto et al 2017;Babich 2017). Obviously, the knowledge of 14 C production rate in the atmosphere is important for precise dating.…”

Russian studies of atmospheric electricity in 2015–2018

“…Данные об усилениях потока нейтронов во время грозы также с успехом применены для исследования грозовых ядерных реакций [79]. Проведена проверка предположения о том, что усиление потока нейтронов обусловлено фотоядерными реакциями за счет гамма-квантов тормозного излучения лавин убегающих электронов высоких энергий, способных развиваться в грозовом электрическом поле.…”

Thunderous nuclear reactions

“…These isotopes include nitrogen-15, carbon-13 and carbon-14, the last of which is widely used in the dating of archaeological artefacts and artworks. In fact, the contribution of thunderstorms to Earth's carbon-14 abundance could be comparable in some regions to that of cosmic irradiation 14 . Future studies should check whether thunderstorms produce other isotopes (such as those of hydrogen, helium and beryllium).…”