Constraints on long-term changes in solar activity from the range of variability of cosmogenic radionuclide records
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Date
2011-09-03
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Copernicus Publications
Abstract
There is a variety of different cosmogenic
radionuclide-based reconstructions of solar activity variations
for the past. Especially the longer-term changes and
the absolute levels of past solar activity are uncertain as it is
illustrated by the differences between these reconstructions.
On the one hand there are differences between 10Be and 14C
records that are commonly used as proxies for the varying solar
modulation of galactic cosmic rays. On the other hand estimates
of past changes in the geomagnetic shielding also include
relatively large uncertainties. Here, we concentrate on
variations in cosmogenic radionuclide records on time scales
of 50 to 500 yr. We show that these are to a large extent
independent of the geomagnetic field intensity. The range
of variability of cosmogenic radionuclide records allows us
to set constraints about long-term changes in solar activity.
These records indicate that present solar activity levels were
reached or exceeded regularly in the past. © Author(s) 2011.
Description
Keywords
Solar activity, Radioisotopes, Cosmology, Beryllium 10, Carbon 14, Cosmic ray spectrometers
Citation
Muscheler, R. and Heikkilä, U., (2011). Constraints on long-term changes in solar activity from the range of variability of cosmogenic radionuclide records. Astrophysics and Space Sciences Transactions, 7(3), 355-364. doi:10.5194/astra-7-355-2011