It is planned to gather international experts from solar, cosmic-ray, atmospheric physics, and related disciplines at the proposed 3-day workshop to attack several particularly important questions in studies of extreme particle storms and their influence on the Earth. The planned activity will combine experts’ review talks of the present state of the art followed by roundtable brainstorming to harmonize and synchronise efforts of different groups in research of extreme solar storms and their possible consequences at the Earth. Three main directions of this field will be addressed at the planned event:

(1) the physics behind occurrence of the extreme particle storms at the Sun,

(2) search and reconstructions of past storms,

(3) effects induced by the storms at the Earth.

Each direction will be discussed during one workshop day – talks during the morning session will be followed by brainstorming in the afternoon session.

Fortunately, no extreme solar storms happened during the modern space era, but they are low probability but extremely dangerous events, that can damage a very large fraction of the space-borne infrastructure of our society (e.g., satellite navigation, communication, meteorological services) and induce major health risks for people working in space. The extreme solar storms are also important to study from the solar physics perspective: how can our Sun accelerate so many particles to such high energies? All those theoretical and practical sides of the phenomenon are currently in intensive studies.