Direct evidence of solar flare modification of stratospheric electric fields is presented through comparison of atmospheric electric field variations with fluxes of solar protons that bombarded the atmosphere during the August 1972 solar flares. Observed order of magnitude variations of the vertical electric field at 30-km altitude in anticorrelation with the intensity of solar protons are quantitatively interpreted in terms of atmospheric conductivity variations produced by solar proton ionization of the air. Other geophysical data are presented which indicate the state of the magnetosphere during this epoch and which further indicate a phenomenological coupling between atmospheric and extraterrestrial events.