Auroral photometric measurements were carried out at South Pole, Antarctica (74.5¿ invariant latitude), throughout the austral winter of 1972. Observed auroral emissions included 4278 ¿ N2 +, 4861 ¿ H&bgr; 5577 ¿ I, and 6300 ¿ I. A comprehensive study of auroral emissions and riometer absorption associated with the solar flare activity of August 1972 has been carried out. Energetic solar protons (>1 MeV) measured by satellite detectors over the polar caps were found to be reasonable for the measured 30-MHz absorption in both the northern and the southern hemispheres, except for two substorm-related events. These protons account for only a fraction of the measured 4278 ¿ N2 + with the remainder of the emissions excited by protons and electrons of lower energies. Simultaneous photometric measurements and riometer observations allow separation of precipitating particle species and characteristic energy, which in turn allows separation of substorm effects from energetic solar proton effects. |