Statistical analysis of the 1995 ground-based ultraviolet radiation (UVR) of Chile and Argentina is presented. The data was obtained from a 7-instrument network that started on July 1997 with uniform data acquisition procedures, cross calibrations and common data processing. We characterize daily and annual cycles of radiation at 305 nm, 340 nm and the ratios of 305/340 and 305/PAR (Photosynthetically Available Radiation) at 7 different localities between 55-23 degrees S based on hourly and monthly means. Extreme radiation in any given locality is presented by contrasting noon radiation on summer clear days with those of winter. Autocorrelation analysis is used to determine the periodicity, if any, of high and low radiation events at 305 nm, 340 nm and the ratio of 305/PAR in order to estimate UVR exposure of local ecosystems.