Astrophysics and Space Sciences Transactions
www.astrophys-space-sci-trans.net
1810-6528
1810-6536
4
1
2008
10.5194/astra-4-1-2008
http://www.astrophys-space-sci-trans.net/4/1/2008/
http://www.astrophys-space-sci-trans.net/4/1/2008/astra-4-1-2008.html
http://www.astrophys-space-sci-trans.net/4/1/2008/astra-4-1-2008.pdf
1
6
2008-02-05
Solar modulation during the Holocene
F. Steinhilber
friedhelm.steinhilber@eawag.ch
J. A. Abreu
J. Beer
Eawag, Aquatic Science, Surface Waters – Radioactive Tracers, Überlandstrasse 133, 8600 Dübendorf, Switzerland
We built a composite of three reconstructions of the solar modulation function
over the Holocene. The reconstructions until 1950 are based on data from
cosmogenic radionuclides and the present time (1951–2004) on neutron monitor data.
<br><br>
Interpreting our composite as an index of solar activity, we were able
to compare the current solar activity with the last
9300 years. During this time span 25 periods with similar high activity than the current
period were found. That corresponds to about 15% of the time which lead to
the conclusion that currently the Sun is very but not exceptionally active.
<br><br>
Our composite has a large potential for studies dealing with solar activity like
the understanding of the solar dynamo and the reconstruction of solar forcing.
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