CLOC – Cosmic Links between Ocean sediments and Ice Cores

The Earth system is characterized by complex interactions whose dynamics and causalities are not fully understood. Feedbacks between different processes may cause the crossing of tipping-points leading to a new state of the climate system. This happened multiple times in the past and allows us to study the underlying processes.

The Helmholtz Young Investigator Group CLOC strives towards improving our understanding of these processes. Better dating methods are a key prerequisite in order to achieve this. Only they allow us to precisely compare different climate archives such as ice cores, sediments, tree-rings or speleothems which all hold pieces to the puzzle. CLOC investigates how we can use cosmogenic radionuclides such as 10Be, 14C, 36Cl, 26Al in order to synchronize different climate archives at high precision.

The ticking of the cosmic clock

Cosmogenic radionuclides are produced by incoming galactic cosmic rays in the upper atmosphere. During increased fluxes of cosmic rays more cosmogenic radionuclides are being produced then during phases of low cosmic ray intensity – a global signal which depends on the strength of the geomagnetic field and solar activity. The cosmogenic radionuclides are subsequently deposited in various climate archives and hence, allow a reconstruction of this signal. Using this, we can not only reconstruct past changes in solar activity and geomagnetic field strength, but also synchronize those climate archives with each other.

CLOC’s research deals with improving and applying this methodology to different regions, timescales and phenomena in the climate history.