Goettingen – An event that shocked planet Earth took place during the last ice age (about 41,400 years ago): evidence of the almost complete reversal of Earth’s magnetic field has been found in ice extracted at very great depths of the South Pole. Scientific Reports magazine is the first to publish the paper authored by an international team of experts led by the chemists at the University of Florence Rita Traversi, Roberto Udisti, Mirko Severi and Silvia Becagli. The group demonstrated the effectiveness of nitrates stratigraphy (present in the ice cores extracted at the Pole) as indicators to reconstruct the past flow of cosmic rays. The research was conducted as part of the EPICA international project – European Project for Ice Coring in Antarctica. The Florentine researchers – in collaboration with colleagues Sami Solanki from the Max-Planck Institute for Solar System Research in Göttingen (Germany) and Ilya Usoskin of the Department of Physics, University of Oulu (Finland) – tested the sensitivity of the nitrates stratigraphy flux of cosmic rays, demonstrating their effectiveness as indicators of a particular event, known as “Laschamp”: a strong anomaly in the concentration profile of beryllium 10 (10Be) occurred about 41,400 years ago, due to a significant peak in the Earth’s magnetic field. (9Colonne)
