Reconstructing solar activity variability beyond the time scale of actual measurements provides invaluable data for modeling of past and future climate change. The 10Be isotope has been a primary proxy archive of past solar activity and cosmic ray intensity, particularly for the last millennium. There is, however, a lack of direct high-resolution atmospheric time series on 10Be that enable estimating atmospheric modulation on the production signal. Here we report quasi-weekly data on 10Be and 7Be isotopes covering the periods 1983-2000 and 1975-2006 respectively, that show, for the first time, coherent variations reflecting both atmospheric and production effects. Our data indicate intrusion of stratosphere/upper troposphere air masses that can modulate the isotopes production signal, and may induce relative peaks in the natural 10Be archives (i.e., ice and sediment). The atmospheric impact on the Be-isotopes can disturb the production signals and consequently the estimate of past solar activity magnitude.
ASJC Scopus subject areas
- Earth and Planetary Sciences(all)