What’s the time? Using cosmogenic radionuclides to test and improve chronologies in paleoclimatology

Mar 8, 2021, 13:15 Uhr

MARUM Research Seminar

via Zoom

Florian Adolphi

Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research

During the limited mode of operation due to corona, the lectures are held virtually via Zoom. Please register by contacting Maximilian Vahlenkamp ([Bitte aktivieren Sie Javascript]) to receive the access link.

Chronology is a key-concern in basically all paleo-sciences. It allows us to compare records, infer dynamics, and elucidate mechanisms of past environmental changes. Yet, it is a major challenge to construct chronologies that are sufficiently precise to do so. Furthermore, not all archives can be dated using the same method, and hence, also the consistency between timescales (radiocarbon, ice core, U/Th..) becomes a concern when combining different records.

Cosmogenic radionuclides provide a unique opportunity to overcome some of these challenges. Their production rates are modulated by the Sun’s and Earth’s magnetic field. Hence, they provide an extra-terrestrial, pulsating signal, that can be measured in a multitude of archives and allows their synchronization.

In this presentation, I will show examples of how we can use this tool to test and improve ice-core and radiocarbon timescales and, ultimately, improve our understanding of paleoclimate dynamics. I will discuss the advantages and challenges of this method and how to expand it to the marine realm.