Abstract. To shed light on potential differences in the magnetosphere-solar wind coupling processes between both cycles, this study examines the link between solar wind characteristics and the Dst index during Solar Cycles (SCs) 24 and 25. In this study, we look into the correlation between geomagnetic storms and several solar wind parameters (solar wind speed, solar wind plasma temperature, solar wind proton density, and flow pressure), sunspot number, Ey, cosmic ray intensity (CRI) and geomagnetic index Dst for SC 24 (start Dec 2008 to end Dec 2019) and SC 25 (start Dec 2019 to 10th August 2023). With the use of the superposed epoch method (Chree analysis), comparative research has been conducted. Solar wind plasma temperature is a geoeffective parameter for SC 24, according to the findings of the current investigation. Compared to other solar wind parameters, the temperature (0.7) of the solar wind has a stronger link with geomagnetic storms. For SCs 24 and 25, the correlation between Dst and CRI is 0.2 and 0.9, respectively. SC 24 and 25 for Dst and Ey have correlations of -0.5 and -0.9, respectively. These variables are highly correlated. There is a modest link between sunspot number and Dst. Which solar wind parameter increases or causes these severe geomagnetic storms was the primary motivation for this investigation. Such understandings are essential for enhancing our capacity to forecast and mitigate the effects of geomagnetic storms on technological systems and societal infrastructure, as well as our comprehension of the dynamics of space weather.

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