Galaktiset kosmiset säteet ja äärimmäiset aurinkotapahtumat tuottavat kosmogeenisia isotooppeja maan atmosfäärillä

This study focuses on the modeling, verification, and parametrization of the atmospheric
production, transport, and deposition of cosmogenic isotopes induced by galactic cosmic
rays (GCR) and solar energetic particles (SEP). Cosmogenic isotopes, such as beryllium7 (7Be), beryllium-10 (10Be), carbon-14 (14C), and chlorine-36 (36Cl), are produced
in the Earth’s atmosphere through interactions between cosmic rays and atmospheric
constituents. The research aims to develop a comprehensive model that simulates the
production and distribution of cosmogenic isotopes in the Earth’s atmosphere for various
scenarios. The chemistry-climate model (CCM) SOCOL is employed, incorporating
modules for the production, transport, and deposition of cosmogenic isotopes induced by
GCRs and SEPs for different solar activity levels and for extreme events. By comparing
the simulated isotopic concentrations with their actual measurements from ice cores
and other natural archives, the model is verified and validated. The comparisons
cover different latitudinal zones, including polar regions, and span temporal scales
ranging from year-to-year variations ((inter)annual) to changes that occur over many
years or decades (long-term). The results confirm the model’s ability to reproduce the
atmospheric transport and deposition of cosmogenic isotopes. The simulations capture
the zonal mean distribution of isotopes in the stratosphere and troposphere, considering
the effects of cosmic ray spectra, geomagnetic shielding, and tropopause characteristics.
The model successfully reproduces the observed concentrations and temporal variability
of isotopes on different time scales, including the solar cycle.
This study emphasizes the significance of realistic modeling and verification of
cosmogenic isotopes, including 7Be, 10Be, 14C, and 36Cl in investigating the atmospheric
effects of cosmic rays and solar energetic particles. The model’s accuracy and validation
against real data provide more information on the production, distribution, and long-term
variability of cosmogenic isotopes in response to solar activity, providing assessments of
the atmospheric impacts of extreme solar events.