Significant effects on the concentration and temperature of ozone in the upper atmosphere were observed during a major solar flare, and subsequent geomagnetic storm, which occurred during the interval August 6 to September 4, 1953. Ozone concentrations, as measured by the absorption of solar radiation by the 9.6 micron ozone band, decreased during the event but retuned to previous levels after the event. Temperature changes were also observed. The changes lag changes in Kp, the geomagnetic activity index, by approximately 5 to 7 days. ¿ American Geophysical Union 1995