Results 21 to 30 of about 8,624 (295)
An Overview of Sunspot Observations in the Early Maunder Minimum: 1645 – 1659
, 2023 Hayakawa et al. (2024) derived sunspot group number and individual sunspot number in the early Maunder Minimum. See their details in Hayakawa et al.
早川, 尚志, Hayakawa, Hisashi
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Ratio Mathematica, 2020 The 11 year sunspot number cycle has been a fascinating phenomenon for many scientists in the last three centuries. Various mathematical functions have been used for modelling the 11 year sunspot number cycles.
Amaranathan Sabarinath +2 more
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Identification of possible intense historical geomagnetic storms using combined sunspot and auroral observations from East Asia [PDF]
Annales Geophysicae, 2005 Comprehensive catalogues of ancient sunspot and auroral observations from East Asia are used to identify possible intense historical geomagnetic storms in the interval 210 BC-AD 1918. There are about 270 entries in the sunspot catalogue and about 1150
D. M. Willis +4 more
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Change of Sunspot Groups Observed from 2002 to 2011 at ButterStar Observatory [PDF]
Journal of Astronomy and Space Sciences, 2012 Since the development of surface magnetic features should reflect the evolution of the solar magnetic field in the deep interior of the Sun, it is crucial to study properties of sunspots and sunspot groups to understand the physical processes working ...
Sung-Jin Oh, Heon-Young Chang
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Fractal Dimension and Maximum Sunspot Number in Solar Cycle [PDF]
Journal of Astronomy and Space Sciences, 2006 The fractal dimension is a quantitative parameter describing the characteristics of irregular time series. In this study, we use this parameter to analyze the irregular aspects of solar activity and to predict the maximum sunspot number in the following ...
R.-S. Kim +4 more
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The proposed “Waldmeier discontinuity”: How does it affect to sunspot cycle characteristics?
Journal of Space Weather and Space Climate, 2012 Recently, Svalgaard has proposed that Waldmeier introduced a discontinuity in the International Sunspot Number (ISN) around 1945. In this paper, we study some characteristics of the sunspot cycle using the classical ISN and the proposed version derived ...
Pérez Aparicio Alejandro Jesús +2 more
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SUNSPOTS AND CREDIT FRICTIONS [PDF]
Macroeconomic Dynamics, 2012 We examine a general equilibrium model with collateral constraints and increasing returns to scale in production. The utility function is nonseparable, with no income effect on the consumer's choice of leisure. Unlike this model without a collateral constraint, we find that indeterminacy of equilibria is possible.
Harrison, S., Weder, M.
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Statistics of sunspot group clusters
Journal of Space Weather and Space Climate, 2013 The Zubrzycki method is utilized to find all sunspot groups which are close to each other during each Carrington rotation. The sunspot group areas and their positions for the years 1874–2008 are used.
Getko Ryszarda
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Solar flare forecasting using morphological properties of sunspot groups
Journal of Space Weather and Space Climate, 2019 We describe a new tool developed for solar flare forecasting on the base of some sunspot group properties. Assuming that the flare frequency follows the Poisson statistics, this tool uses a database containing the morphological characteristics of the ...
Falco Mariachiara +2 more
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The effects of changing solar activity on climate: contributions from palaeoclimatological studies
Journal of Space Weather and Space Climate, 2012 Natural climate change currently acts in concert with human-induced changes in the climate system. To disentangle the natural variability in the climate system and the human-induced effects on the global climate, a critical analysis of climate change in ...
Engels Stefan, van Geel Bas
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