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Revisiting the Sunspot Number
Our knowledge of the long-term evolution of solar activity and of its primary modulation, the 11-year cycle, largely depends on a single direct observational record: the visual sunspot counts thatExpand
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Reconstruction of the Sunspot Group Number: The Backbone Method
We have reconstructed the sunspot-group count, not by comparisons with other reconstructions and correcting those where they were deemed to be deficient, but by a re-assessment of original sources.Expand
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Revisiting the Sunspot Number A 400-Year Perspective on the Solar Cycle
Our knowledge of the long-term evolution of solar activity and of its primary modulation, the 11-year cycle, largely depends on a single direct observational record: the visual sunspot counts thatExpand
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The 1859 Solar–Terrestrial Disturbance And the Current Limits of Extreme Space Weather Activity
It is generally appreciated that the September 1859 solar–terrestrial disturbance, the first recognized space weather event, was exceptionally large. How large and how exceptional? To answer theseExpand
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Sunspot cycle 24 : Smallest cycle in 100 years?
Abstract : Predicting the peak amplitude of the sunspot cycle is a key goal of solar-terrestrial physics. The precursor method currently favored for such predictions is based on the dynamo model inExpand
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The strength of the Sun's polar fields
The magnetic field strength within the polar caps of the Sun is an important parameter for both the solar activity cycle and for our understanding of the interplanetary magnetic field. MeasurementsExpand
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The mean magnetic field of the Sun: Observations at Stanford
A solar telescope has been built at Stanford University to study the organization and evolution of large-scale solar magnetic fields and velocities. The observations are made using a Babcock-typeExpand
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Geomagnetic activity: dependence on solar wind parameters.
Abstract : Current ideas about the interaction between the solar wind and the earth's magnetosphere are reviewed. The solar wind dynamic pressure as well as the influx of interplanetary magneticExpand
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Using Dynamo Theory to predict the sunspot number during Solar Cycle 21
On physical grounds it is suggested that the sun's polar field strength near a solar minimum is closely related to the following cycle's solar activity. Four methods of estimating the sun's polarExpand
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Long term evolution of solar sector structure
The large-scale structure of the solar magnetic field during the past five sunspot cycles (representing by implication a much longer interval of time) has been investigated using the polarity (towardExpand
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