Panovska, S., Poluianov, S., Gao, J., Korte, M., Mishev, A., Shprits, Y. Y., & Usoskin, I. (2023). Effects of global geomagnetic field variations over the past 100,000 years on cosmogenic radionuclide production rates in the Earth's atmosphere. Journal of Geophysical Research: Space Physics, 128, e2022JA031158. https://doi.org/10.1029/2022JA031158
Effects of global geomagnetic field variations over the past 100,000 years on cosmogenic radionuclide production rates in the Earth’s atmosphere
|Author:||Panovska, Sanja1; Poluianov, Stepan2,3; Gao, Jiawei1,4,5;|
1GFZ German Research Centre for Geosciences, Section 2.3, Helmholtz Centre Potsdam, Potsdam, Germany
2Sodankylä Geophysical Observatory, University of Oulu, Oulu, Finland
3Space Physics and Astronomy Research Unit, University of Oulu, Oulu, Finland
4Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing, China
5College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing, China
6GFZ German Research Centre for Geosciences, Section 2.7, Helmholtz Centre Potsdam, Potsdam, Germany
7Institute of Physics and Astronomy, University of Potsdam, Potsdam, Germany
8Department of Earth, Planetary, and Space Sciences, University of California, Los Angeles, CA, USA
|Online Access:||PDF Full Text (PDF, 1.9 MB)|
|Persistent link:|| http://urn.fi/urn:nbn:fi-fe2023080493107
American Geophysical Union,
|Publish Date:|| 2023-08-04
The production rates of cosmogenic radionuclides, such as ¹⁰Be, ¹⁴C, and ³⁶Cl, in the Earth’s atmosphere vary with the geomagnetic field and solar activity. For the first time, the production rates of several cosmogenic nuclides are estimated for the past 100 ka based on global, time-dependent geomagnetic field models and a moderate solar-activity level. In particular, the production rates were high with no notable latitudinal dependence during the Laschamps geomagnetic excursion (41 ka BP). The mean global production of ¹⁰Be over the Laschamps excursion was more than two times greater than the present-day one, whereas the increase was 1.9 times for the Norwegian-Greenland Sea excursion (∼65 ka), and only 1.3 times for the Mono Lake/Auckland excursion (∼34 ka). All analyzed geomagnetic field models covering the past 100 ka, including the modern and Holocene epochs, lead to hemispheric asymmetry in the production rates, persistent overall time ranges, and reflected in the time-averaged nuclide production rates. Production rates predicted by the geomagnetic field models are in good agreement with actual measurements from ice cores and sediment records. These global, long-term production rates are important for a wide range of studies that employ cosmogenic nuclides as a proxy/tracer of different Earth system processes.
Journal of geophysical research. Space physics
|Type of Publication:||
A1 Journal article – refereed
|Field of Science:||
115 Astronomy and space science
The University of Oulu team acknowledges support from the Academy of Finland, project GERACLIS Grant 354280 and QUASARE Grant 330064, and the UO grant SARPEDON.
|Academy of Finland Grant Number:||
354280 (Academy of Finland Funding decision)
330064 (Academy of Finland Funding decision)
The cosmogenic nuclide production rates presented here are available in the EarthRef.org Digital Archive (ERDA) at https://earthref.org/ERDA/2543/. The cutoff rigidities are analyzed and presented in Gao et al. (2022a, 2022b), available online at https://earthref.org/ERDA/2498/ and https://earthref.org/ERDA/2521/. The yield functions of cosmogenic nuclides are available in the supplementary material of Poluianov et al. (2016).
© 2023. The Authors.This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.