Author(s): Nethaneel Taylor
Mentor(s): Richard Medina
Institution SUU
This study investigates the variation in UV and visible light irradiance in Cedar City, UT, by modifying the TUV (Tropospheric Ultraviolet and Visible) radiation model to incorporate local atmospheric conditions. The model was used to simulate irradiance levels for different wavelengths of UV and visible light at various times of day and elevations. The study specifically examines irradiance during the months of the COVID-19 lockdown (March through August 2020) compared to the months of March through August 2024. The TUV model inputs were tailored with local data, including atmospheric concentrations of NO2, ozone, and aerosol optical depths, which were obtained from NASA Worldview and integrated into the model to refine its accuracy. The study determined how well a numerical radiative transfer model analyzed environmental conditions and atmospheric optical parameters, particularly the presence of aerosols and changes in air quality during each of the atmospheric settings, had a significant impact on UV and visible light irradiance. During the COVID-19 lockdown, lower levels of air pollution improved irradiance levels, particularly for UVB radiation, compared to pre-lockdown conditions. The present year clear summer days served as a baseline for comparison, highlighting the role of local air quality in modulating the solar spectrum. This model shows how trends in parameters such as NO2, ozone, and aerosol optical depth levels can be used to predict irradiation and atmospheric health. This research provides valuable insights into how atmospheric conditions, such as pollutant levels and aerosols, affect solar radiation at ground level, and it demonstrates the utility of the TUV model for localized, real-time irradiance forecasting. This work contributes to the broader understanding of how environmental factors influence solar energy and UV exposure, which can have implications for public health, environmental monitoring, and solar energy applications in regions with varying air quality.