98 citations · 98 across the 1 of their papers we have counts for
4 papers
A solar cycle lost in 1793--1800: Early sunspot observations resolve the old mystery
Ilya G. Usoskin, Kalevi Mursula, Rainer Arlt +1
Because of the lack of reliable sunspot observation, the quality of sunspot number series is poor in the late 18th century, leading to the abnormally long solar cycle (1784--1799)…
Preferred sunspot longitudes: Non-axisymmetry and differential rotation
I. G. Usoskin, S. V. Berdyugina, J. Poutanen
As recently found, the distribution of sunspots is non-axisymmetric and spot group formation implies the existence of two persistent active longitudes separated by 180 degrees. Her…
A Millennium Scale Sunspot Number Reconstruction: Evidence For an Unusually Active Sun Since the 1940's
Ilya G. Usoskin, Sami K. Solanki, Manfred Schuessler +2
The extension of the sunspot number series backward in time is of considerable interest for dynamo theory, solar, stellar, and climate research. We have used records of the Be-10 c…
Reconstruction of solar activity for the last millennium using Be data
I. G. Usoskin, K. Mursula, S. Solanki +2
In a recent paper (Usoskin et al., 2002a), we have reconstructed the concentration of the cosmogenic Be isotope in ice cores from the measured sunspot numbers by using physi…