Understanding the Cause-Effect Chain from Sun to Earth of Geo-Events

Abstract:

A new 5-year (2014-2018) SCOSTEP program Variability of the Sun and Its Terrestrial Impact (VarSITI) focuses on the current period of low solar activity and its consequences at Earth. ISEST (International Study of Earth-affecting Solar Transients) is the VarSITI project whose goal is to understand the origin, evolution and propagation of solar transients (CMEs, flares, CIRs) through the space between the Sun and Earth, with the goal of improving the prediction capability for space weather. ISEST provides textbook cases to the community, and its Working Group 4 on Campaign Events is studying less well understood events, such as so-called stealth and problem CMEs. We highlight several case studies of recent Sun-Earth events for which there was a problem in forecasting the geoactivity, but we now understand what happened.