Cosmic Rays and Space Weather Prediction

Abstract

Galactic and solar cosmic rays registered by neutron monitors can play a useful key-role in space weather storms forecasting and in the specification of magnetic properties of coronal mass ejections, shocks and ground level enhancements. In order to produce a real-time prediction of space weather phenomena, only real-time data from a neutron monitor network should be employed. Interplanetary perturbations, initiated in the solar atmosphere, affect galactic cosmic rays. In some cases their influence on the cosmic ray intensity results in data signatures that can pos- sibly be used to predict geomagnetic storm onsets. The concept of Space Weather was launched before a decade to describe the short-term variations in the different form of solar activity and their effect in the near Earth environment. Space weather affects the Earth's atmosphere in many ways and through various phenomena. Among them, geomag- netic storms and the variability of the galactic cosmic ray flux belong to the most important ones as for the lower at- mosphere. We have performed superposed epoch analysis using hourly neutron monitor data for three different ground-based neutron-monitoring stations of different cut off rigidity as a measure of cosmic ray intensity. In the present work the superposed epoch analysis has been done for the time of occurrence of CMEs are defined as key time (zero or epoch hour/day). It is noteworthy that the use of cosmic ray data in space weather research plays a key role for its prediction. We have studied the cosmic ray, geomagnetic and interplanetary plasma/field data to under- stand the physical mechanism responsible for Forbush decrease and geomagnetic storm that can be used as a signa- ture to forecast space weather.