The Magnitude of IMF By Influences the Magnetotail Response to Solar Wind Forcing Journal of Geophysical Research: Space Physics

Substorms are global magnetic disturbances in which energy stored in the Earth’s magnetic field is suddenly released, leading to intense aurorae and other space weather effects. Substorms are most frequent and strongest when the magnetic field incident to the Earth at the Sun-Earth line has a strong southward component. In this paper we study how the occurrence and strength of substorms are affected by the east component of this magnetic field. We show that substorms are less frequent but stronger, with associated aurora extending to lower latitudes, when the east component is strongly positive or negative. These results help in developing more accurate space weather predictions in the future.