Climate variability in a 3.8 Ma old sedimentary record from the hyperarid Atacama Desert

Author(s)

Felix L. Arens, Jenny Feige, Alessandro Airo, Christof Sager, Lutz Hecht, Lucas Horstmann, Felix E.D. Kaufmann, Johannes Lachner, Thomas Neumann, Norbert Nowaczyk, Ferry Schiperski, Peter Steier, Alexandra Stoll, Ulrich Struck, Bernardita Valenzuela, Friedhelm von Blanckenburg, Hella Wittmann, Lukas Wacker, Dirk Wagner, Pedro Zamorano, Dirk Schulze-Makuch

Abstract

The hyperarid Atacama Desert is one of the driest and oldest deserts on Earth, rendering it a valuable climate archive. However, unraveling its past climate is particularly challenging and the few studied paleoclimate records of the region reveal strong temporal and spatial variabilities. To enhance our understanding of these dynamics we investigated a sedimentary record in the Yungay valley located in the southern hyperarid Atacama Desert. We employed paleomagnetic and radiocarbon dating, and for the first time for Atacama Desert sediments, a meteoric ¹⁰Be/⁹Be based method for determining the depositional age. The respective 4.20 m deep profile comprises a lower alluvial fan deposit with a maximum age of 3.8 ± 0.8 Ma, and an upper 1.84 m thick clay pan deposit that has accumulated over the last 19 ka. Different proxies including grain size, salt concentration, and elemental composition indicate an aridity increase around 2.3 Ma ago and repeated dry and wet phases during the late Pleistocene and the Holocene. The latter climatic shifts can be assigned to variabilities of the South American Summer Monsoon and El Niño Southern Oscillation with moisture sources from the Atlantic and the Pacific Ocean, respectively. This study provides deeper insights into the heterogeneous climate of the hyperarid Atacama Desert and underlines the importance of interdisciplinary investigations to decipher climate systems and their effect on potential habitable regions in such an extreme environment.

Organisation(s)

Isotope Physics

External organisation(s)

Technische Universität Berlin, Museum für Naturkunde Berlin - Leibniz-Institut für Evolutions- und Biodiversitätsforschung, Helmholtz-Zentrum Potsdam Deutsches GeoForschungsZentrum, Georg-August-Universität Göttingen, Helmholtz-Zentrum Dresden-Rossendorf, Centro de Estudios Avanzados en Zonas Áridas (CEAZA), Universidad de La Serena, Universidad de Antofagasta, Freie Universität Berlin (FU), Eidgenössische Technische Hochschule Zürich, Universität Potsdam, GFZ German Research Centre for Geosciences

Journal

Global and Planetary Change

Volume

242

No. of pages

17

ISSN

0921-8181

DOI

https://doi.org/10.1016/j.gloplacha.2024.104576

Publication date

11-2024

Peer reviewed

Yes

Austrian Fields of Science 2012

105204 Climatology, 105205 Climate change, 105121 Sedimentology

Keywords

ASJC Scopus subject areas

Global and Planetary Change, Oceanography

Sustainable Development Goals

SDG 13 - Climate Action

Portal url

https://ucrisportal.univie.ac.at/en/publications/b5b501b8-d0a2-4b7d-8311-1f9ad55209de