The Great Space Weather Storm of May 1967: How It Nearly Changed Everything

Although listed as one of the most significant events of the last 80 years, the space weather storm of late May 1967 has been largely forgotten. I will explain how the May 1967 storm was nearly one with ultimate societal impact, were it not for the nascent efforts of the United States Air Force in expanding its terrestrial weather monitoring-analysis-warning-prediction efforts into the realm of space weather forecasting.  During that event an initial “great” solar radio burst, which caused radio interference at frequencies between 0.01-9.0 GHz, was accompanied by near-simultaneous disruptions of dayside radio communication by intense fluxes of ionizing solar X-rays.  Aspects of military control and communication were immediately challenged.  Shortly thereafter a solar energetic particle event interfered with high-frequency communication in the polar cap. Subsequently, record-setting geomagnetic and ionospheric storms compounded the disruptions. I detail three aspects of the storm:  The great radio burst; the solar energetic particles; and the surprising effects on upper atmospheric temperature. As noted in Knipp et al. [2016] this was one of the “Great Storms” of the 20^th century, despite the lack of large, geomagnetically-induced currents.  Radio disruptions like those discussed here warrant the attention of today’s radio-reliant, cellular-phone and satellite-navigation enabled world.

Knipp, D. J.,  A. C. Ramsay, E. D. Beard, A. L. Boright, W. B. Cade, I. M. Hewins, R. McFadden, W. F. Denig, L. M. Kilcommons, M. A. Shea and D. F. Smart (2016), The May 1967 Great Storm and Radio Disruption Event: Extreme Space Weather and Extraordinary Responses, (Accepted in Space Weather)