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Related papers: On Predicting the Solar Cycle using Mean-Field Mod…

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We explore the capabilities of time-dependent (TD) magnetohydrodynamics (MHD) solar wind simulations with the coupled WSA model of the solar corona and GAMERA model of the inner heliosphere. We compare TD with steady state (SS) simulations…

Solar and Stellar Astrophysics · Physics 2025-09-26 Evangelia Samara , Elena Provornikova , C. Nick Arge , Andrew McCubbin , Viacheslav G. Merkin

The operation of the solar dynamo, with all of its remarkable spatio-temporal ordering, remains an outstanding problem of modern solar physics. A number of mechanisms that might plausibly contribute to its operation have been proposed, but…

Parameters of magnetic activity on the solar type stars depend on the properties of the dynamo processes operating in stellar convection zones. We apply nonlinear mean-field axisymmetric $\alpha^2\Omega$ dynamo models to calculate of the…

Solar and Stellar Astrophysics · Physics 2015-05-08 V. V. Pipin

Using a nonlinear mean-field solar dynamo model, we study relationships between the amplitude of the `extended' mode of migrating zonal flows (`torsional oscillations') and magnetic cycles, and investigate whether properties the torsional…

Solar and Stellar Astrophysics · Physics 2020-09-02 V. V. Pipin , A. G. Kosovichev

It is shown that the description of the solar cycle that takes into account the odd zonal harmonic of the solar magnetic field allows us to deepen our knowledge of two important aspects of the solar activity. First, to clarify and expand…

Solar and Stellar Astrophysics · Physics 2023-11-02 V. N. Obridko , D. D. Sokoloff , M. M. Katsova

The dynamic activity of the Sun, governed by its cycle of sunspots -- strongly magnetized regions that are observed on its surface -- modulate our solar system space environment creating space weather. Severe space weather leads to…

Solar and Stellar Astrophysics · Physics 2020-05-26 Aleix Espuña-Fontcuberta , Saikat Chatterjee , Dhrubaditya Mitra , Dibyendu Nandy

The Sun and solar-type stars exhibit irregular cyclic variations in their magnetic activity over long time scales. To understand this irregularity, we employed the flux transport dynamo models to investigate the behavior of one solar mass…

Solar and Stellar Astrophysics · Physics 2024-12-25 Vindya Vashishth

The polar magnetic field precursor is considered to be the most robust and physics-based method for the prediction of the next solar cycle strength. However, to make a reliable prediction of a cycle, is the polar field at the solar minimum…

Solar and Stellar Astrophysics · Physics 2022-02-09 Pawan Kumar , Bidya Binay Karak , Vindya Vashishth

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 insufficient length of the directly observed solar activity…

Solar and Stellar Astrophysics · Physics 2014-02-24 I. G. Usoskin , G. Hulot , Y. Gallet , R. Roth , A. Licht , F. Joos , G. A. Kovaltsov , E. Thebault , A. Khokhlov

Measuring the depth variation of the meridional flows is important for understanding the solar cycle, at least according to a number of dynamo models. While attempting to extend the early observations of \citet{giles_thesis} of…

Solar and Stellar Astrophysics · Physics 2012-08-27 Thomas L. Duvall, , Shravan M. Hanasoge

The duration of activity growths in solar cycles is on average shorter than the duration of its declines. This asymmetry can result from fluctuations in dynamo parameters. A solar dynamo model with fluctuations in the $\alpha$-effect shows…

Solar and Stellar Astrophysics · Physics 2018-11-07 Leonid Kitchatinov , Alexander Nepomnyashchikh

The input of the Solar wind models plays a significant role in accurate solar wind predictions at 1 AU. This work introduces a synthetic magnetogram produced from a dynamo model as an input for Magnetohydrodynamics (MHD) simulations. We…

Solar and Stellar Astrophysics · Physics 2022-10-13 Kalpa Henadhira Arachchige , Ofer Cohen , Andrés Muñoz Jaramillo , Anthony R. Yeates

A two-wave dynamo model was recently proposed by Zharkova et al. (2015, Zh15 henceforth), which aims at long-term predictions of solar activity for millennia ahead and backwards. Here we confront the backward model predictions for the last…

Solar and Stellar Astrophysics · Physics 2015-12-18 I. Usoskin , G. Kovaltsov

Observations of the sun suggest that solar activities systematically create north-south hemispheric asymmetries. For instance, the hemisphere in which the sunspot activity is more active tends to switch after the early half of each solar…

Solar and Stellar Astrophysics · Physics 2017-04-12 D. Syukuya , K. Kusano

We present in this work the development of a solar data assimilation method based on an axisymmetric mean field dynamo model and magnetic surface data, our mid-term goal is to predict the solar quasi cyclic activity. Here we focus on the…

Solar and Stellar Astrophysics · Physics 2017-11-15 Ching Pui Hung , Allan Sacha Brun , Alexandre Fournier , Laurène Jouve , Olivier Talagrand , Mustapha Zakari

Global dynamo simulations solving the equations of magnetohydrodynamics (MHD) have been a tool of astrophysicists who try to understand the magnetism of the Sun for several decades now. During recent years many fundamental issues in dynamo…

Solar and Stellar Astrophysics · Physics 2011-07-08 P. J. Käpylä

We consider the statistical relationship between the growth rate of activity in the early phase of a solar cycle with its subsequent amplitude on the basis of four datasets of global activity indices (Wolf sunspot number, group sunspot…

Astrophysics · Physics 2008-06-18 R. Cameron M. Schüssler

Recent data on superflares on sun-like stars and radiocarbon data on solar activity in the past are both indicative of transient epochs of unusually high magnetic activity. We propose an explanation for the grand activity maxima in the…

Solar and Stellar Astrophysics · Physics 2016-05-05 L. L. Kitchatinov , S. V. Olemskoy

The role of turbulent effects for dynamos in the Sun and stars continues to be debated. Mean-field (MF) theory provides a broadly used framework to connect these effects to fundamental magnetohydrodynamics. While inaccessible…

Solar and Stellar Astrophysics · Physics 2021-10-06 Jörn Warnecke , Matthias Rheinhardt , Mariangela Viviani , Frederick Gent , Simo Tuomisto , Maarit J. Käpylä

Several energy management applications rely on accurate photovoltaic generation forecasts. Common metrics like mean absolute error or root-mean-square error, omit error-distribution details needed for stochastic optimization. In addition,…

Machine Learning · Computer Science 2026-03-05 Philipp Danner , Hermann de Meer