Earth’s atmosphere protects the biosphere from nearby supernovae

Autor(en)

Theodoros Christoudias, Jasper Kirkby, Dominik Stolzenburg, Andrea Pozzer, Eva Sommer, Guy P. Brasseur, Markku Kulmala, Jos Lelieveld

Abstrakt

Geological evidence indicates that a supernova within 100 parsecs of Earth occurs around once per million years. Such nearby supernovas can produce an intense gamma-ray burst and a 100-fold increase of cosmic rays, lasting several centuries. We find that the effect of a short burst of gamma rays is small since they are strongly attenuated before reaching the lower stratosphere. Intense cosmic radiation affects stratospheric ozone but, due to compensating effects in catalytic chemical cycles, ozone depletion is moderate and comparable to that from current anthropogenic emissions. This also holds for the low-oxygen atmosphere during early evolution of terrestrial life. We estimate the increase in aerosol and clouds from a 100-fold increase of cosmic rays exerts a radiative forcing comparable in magnitude but opposite in sign to current anthropogenic climate forcing. We conclude that Earth’s atmosphere is effective at shielding the biosphere from nearby supernovae.

Organisation(en)

Aerosolphysik und Umweltphysik

Externe Organisation(en)

The Cyprus Institute, Johann Wolfgang Goethe-Universität Frankfurt am Main, European Organization for Nuclear Research (CERN), Technische Universität Wien, Max-Planck-Institut für Chemie (Otto-Hahn-Institut), National Center for Atmospheric Research (NCAR), University of Helsinki, Nanjing University, Beijing University of Chemical Technology

Journal

Communications Earth and Environment

Band

5

Anzahl der Seiten

8

ISSN

2662-4435

DOI

https://doi.org/10.1038/s43247-024-01490-9

Publikationsdatum

06-2024

Peer-reviewed

Ja

ÖFOS 2012

103039 Aerosolphysik, 103037 Umweltphysik, 105208 Atmosphärenchemie, 104023 Umweltchemie

ASJC Scopus Sachgebiete

Allgemeine Umweltwissenschaft, Allgemeine Erdkunde und Planetologie

Sustainable Development Goals

SDG 12 – Nachhaltige/r Konsum und Produktion, SDG 13 – Maßnahmen zum Klimaschutz

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/107f894e-82a8-46d9-97fb-4540afb1ee69