Academy of Finland
Funding decision
Name Holappa, Lauri
Organisation OY
Project title
Explaining a new solar wind driver of geomagnetic activity
Decision No. 322459
Decision date 07.05.2019
Funding period 01.09.2019 - 30.11.2022
Funding 209 680
WebFOCUS Report
Project description
Geomagnetic activity, the variability of the Earth’s magnetic field, is driven by solar wind and the interplanetary magnetic field (IMF). Geomagnetic storms, the extreme form of geomagnetic activity, are the most significant space weather hazards for modern society. Thus, detailed understanding of the relation between geomagnetic activity and solar wind is crucial. It is well known that the most important driver of geomagnetic activity is the north-south (Bz) component of the IMF. However, recent studies have shown that also the east-west (By) component of IMF is responsible for significant amount of geomagnetic activity. The physical mechanism of this new By-effect is still unknown. In this project, ground-based geomagnetic activity measurements from a large network of magnetic stations, satellite and radar observations as well as numerical models to resolve the physical cause of the By-effect.