The relationships of solar flares with both sunspot and geomagnetic activity

TL;DR

This study models the relationships between solar flares, sunspot activity, and geomagnetic activity using an integral response model, revealing time delays and improved correlations that enhance understanding and prediction of solar phenomena.

Contribution

It introduces an integral response model to describe and predict the relationships and time delays between solar flares, sunspot activity, and geomagnetic activity, improving correlation accuracy.

Findings

Correlation coefficients increased by up to 47% using the model.

Time delays of solar phenomena can be predicted with over 78% accuracy.

The model suggests solar flares relate to accumulated magnetic energy with a decay factor.

Abstract

The relationships between solar flare parameters (total importance, time duration, flare index, and flux) and sunspot activity (Rz) as well as those between geomagnetic activity (aa index) and the flare parameters can be well described by an integral response model with the response time scales of about eight and thirteen months, respectively. Compared with linear relationships, the correlation coefficients of the flare parameters with Rz, of aa with the flare parameters, and of aa with Rz based on this model have increased about 6%, 17%, and 47% on average, respectively. The time delays of the flare parameters to Rz, of aa to the flare parameters, and of aa to Rz at their peaks in solar cycle can be predicted in part by this model (82%, 47%, and 78%, respectively). These results may be further improved when using a cosine filter with a wider window. It implies that solar flares are related to the accumulation of solar magnetic energies in the past through a time decay factor. The above results may help to understand the mechanism of the solar cycle and to improve the solar flare prediction.