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arXiv · 1811.01363

A New Formula for Predicting Solar Cycles

Gopal Hazra·Arnab Rai Choudhuri
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Abstract

A new formula for predicting solar cycles based on the current theoretical understanding of the solar cycle from flux transport dynamo is presented. Two important processes---fluctuations in the Babcock-Leighton mechanism and variations in the meridional circulation, which are believed to be responsible for irregularities of the solar cycle---are constrained by using observational data. We take the polar field near minima of the cycle as a measure of the randomness in the Babcock-Leighton process, and the decay rate near the minima as a consequence of the change in meridional circulation. We couple these two observationally derived quantities into a single formula to predict the amplitude of the future solar cycle. Our new formula suggests that the cycle 25 would be a moderate cycle. Whether this formula for predicting the future solar cycle can be justified theoretically is also discussed using simulations from the flux transport dynamo model.

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Gopal Hazra, Arnab Rai Choudhuri. 2019-06-04. A New Formula for Predicting Solar Cycles. https://doi.org/10.3847/1538-4357%2Fab2718

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