129 citations · 291 across the 7 of their papers we have counts for
7 papers
Reconstruction of annual solar irradiance over the last three millennia
D. Temaj, N. A. Krivova, S. K. Solanki +2
Solar irradiance measurements are limited to the last few decades, requiring reconstructions to assess solar variability on longer timescales and its impact on Earth's climate. We…
Full Dynamical Model (SOCOL:14C-Ex) of 14C Atmospheric Production and Transport in Application to Miyake Events
Kseniia Golubenko, Ilya Usoskin, Edouard Bard +2
Extreme solar particle events (ESPEs) are caused by rare, enormously strong solar eruptions and can produce globally detectable spikes in tree-ring radiocarbon 14C, known as Miyake…
Cyclic sunspot activity during the first millennium CE as reconstructed from radiocarbon
Ilya Usoskin, Sami K. Solanki, Natalie A. Krivova +1
Context. Solar activity, dominated by the 11-year cyclic evolution, has been observed directly since 1610. Before that, indirect cosmogenic proxy data are used to reconstruct it ov…
A Test of the Active Day Fraction Method of Sunspot Group Number Calibration: Dependence on the Level of Solar Activity
Teemu Willamo, Ilya G. Usoskin, Gennady A. Kovaltsov
The method of active day fraction (ADF) was proposed recently to calibrate different solar observers to the standard observational conditions. The result of the calibration may dep…
Dependence of the Sunspot-group Size on the Level of Solar Activity and its Influence on the Calibration of Solar Observers
I. G. Usoskin, G. A. Kovaltsov, T. Chatzistergos
The distribution of the sunspot group size (area) and its dependence on the level of solar activity is studied. It is shown that the fraction of small groups is not constant but de…
A New Calibrated Sunspot Group Series Since 1749: Statistics of Active Day Fractions
I. G. Usoskin, G. A. Kovaltsov, M. Lockwood +3
Although the sunspot-number series have existed since the mid-19th century, they are still the subject of intense debate, with the largest uncertainty being related to the "calibra…
Evidence for distinct modes of solar activity
I. G. Usoskin, G. Hulot, Y. Gallet +6
Aims. The Sun shows strong variability in its magnetic activity, from Grand minima to Grand maxima, but the nature of the variability is not fully understood, mostly because of the…