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Abstract

The main purpose of this study is to investigate how the CMEs and HSSs affect upper atmospheric Joule heating using a reasonably large range of parameters. The parameters were chosen to be the basic plasma and magnetic field properties, as well as the derived quantities and ground-level geomagnetic indices. Three CME and HSS events were selected and corresponding Joule heating was obtained from SWMF/BATS-R-US with RCM. To start with, a simple linear regression analysis was applied between the parameters corresponding to CME regions and Joule heating to determine the most influential parameter for the Joule heating rates. Similar analyses were also carried out for the HSS cases. The best correlating parameters among 9 parameters were found to be the southward component of the interplanetary magnetic field, solar wind speed, and AE index. Furthermore, multiple linear regression (MLR) analysis was conducted using the best correlating parameters. In the second part of our study, the Joule heating rates were quantified for CME and HSS-driven storm intervals as well as for the initial, main, and recovery phases of each storm, to reveal the resulting differences. Our results show that the Joule heating rate for CME cases is approximately higher by a factor of 3.3 compared to HSS cases. These results expand our understanding of the relation between the solar and the upper atmospheric phenomena based on Joule heating.