Explaining Empirical Relationships Found in Sunspot Number and Area Time Series with a Simplified Dynamo Model

Abstract:

Ever since Schwabe in 1843 discovered periodicity in sunspot numbers, several empirical relationships have been found between various characteristics of the sunspot number and sunspot area time series. The modulations in sunspot cycle period, amplitude, rise rate, rise time, decline rate, decline time, polar flux, etc. are all embedded in a zoo of possible correlations with each other. In order to pin-point causally connected correlations between these parameters, we employ a simple theoretical approach based on the principles of dynamo theory. Utilizing certain observed facts about the Sun and our theoretical understanding of dynamo theory, we are able to explain most empirical relationships known in the solar physics community. In this process, we also derive and establish new empirical relationships predicted by our theory and ascertain their validity.