Comparison between statistical properties of Forbush decreases caused by solar wind disturbances from coronal mass ejections and coronal holes.

Highlights • Interplanetary mass ejections and high speed streams differ by modulation abilities. • Parameters distributions are more compact for Forbush decreases from coronal holes. • Partial correlation of geomagnetic and Forbush decrease parameters is insignificant. • Correlation of solar wind and recurrent Forbush decrease parameters is moderate. • Correlation of solar wind and sporadic Forbush decrease parameters is high. Abstract In this paper, we compare Forbush decreases associated with solar wind disturbances from two types of solar sources: coronal mass ejections (sporadic Forbush decreases) and coronal holes (recurrent Forbush decreases). We used Forbush Effects and Interplanetary Disturbances database created and maintained by IZMIRAN and associated a certain amount of Forbush decreases in this database with interplanetary disturbances from coronal mass ejections (207 cases) as well as high speed streams from coronal holes (350 cases). Large number of events allows to apply statistical methods (distribution analysis, correlation analysis, multiple linear regression analysis) to compare those two groups of events. The results reveal that Forbush decreases associated with solar wind disturbances from the two types of solar sources differ significantly in their statistical characteristics: distributions, descriptive statistics, correlation and multiple regression coefficients. [ABSTRACT FROM AUTHOR]