This research focuses on data analysis and theoretical modeling of solar radiation in the high latitude Southern Hemisphere using measurements obtained by NSF spectroradiometers located at Palmer Station, Antarctica and Ushuaia, Argentina. The objectives are to define and quantify the physical mechanisms responsible for observed variations in surface irradiance in the ultraviolet and visible regions of the spectrum, with emphasis on the former. Variations to be studied span time scales of hours, associated with fluctuations in cloudiness, to several years, where changes can arise from differences in local cloudiness and ozone levels from one year to the next. Special attention will focus on ultraviolet radiation levels measured during the springtime ozone depletion over Palmer Station and a search for any effects at the lower latitude of Ushuaia. The results will provide a comprehensive description of the radiation environments at Palmer Station and Ushuaia in the visible and biologically relevant ultraviolet portions of the spectrum.
