On one approach to space weather studies from ground based observations during 1953–2001

The cross correlation of daily values of coronal hole areas at the eastern limb of the Sun constructed from the ground based measurements of the green coronal line and daily mean cosmic ray intensities over long time periods shows asymmetry: at the maximum of their 27 day cycle, cosmic ray intensities are better correlated with coronal hole areas ∼66 days before than with the current value. This indicates the potential for using coronal emission data as one of the parameters for eventual prediction of the level of cosmic ray flux at neutron monitor energies.