Marine life in the upper layers of the sea may be endangered by increased UV radiation resulting from reduction in the thickness of the ozone layer. The potential hazard to marine phytoplankton is based upon the knowledge that middle ultraviolet radiation (MUV, 280-340 nm) can penetrate to ecologically significant depths in natural waters and the possibility that MUV may have adverse effects on phytoplankton populations. The direct effects of increased UV on in-situ phytoplankton have not been estimated, although this is the only adequate measure of the potential impact. This research will make a sensitivity analysis of factors influencing the penetration of UV into natural waters based upon existing UV models for the atmosphere and ocean and using TOMS ozone data as input. In addition, this project will focus on equipment development, with a modification or redesign of the existing (and outmoded) ultraviolet submersible spectroradiometer for use in the Antarctic. The model and equipment development are a major step necessary prior to the testing of the hypothesis that phytoplankton, and other subsequently impacted components of the aquatic food web, are endangered by ozone diminution.
