The Impact of Space Weather on Ultraviolet Radiation at Mid Latitudes

Abstract

Solar ultraviolet (UV) radiation plays a crucial role in various environmental, atmospheric, and industrial applications, despite covering only a small portion of the electromagnetic solar radiation. The distribution of UV radiation reaching the Earth’s surface is influenced by multiple environmental, atmospheric, and astronomical factors, some of which require further investigation. The aim of this study is to explore the potential impact of cosmic rays and space weather parameters on solar UV radiation. To achieve this, the study utilized solar UV data collected from the King Abdulaziz City for Science and Technology (KACST) radiometric station, situated in central Saudi Arabia (latitude 24 43, longitude 46 40, altitude 613 m) for the period 2015–2021, along with space weather parameters. These parameters include solar radio flux at 10.7 cm (F10.7 cm) and sunspot number (SSN), as well as cosmic ray data from the Oulu neutron monitor for the same period as the UV data. The study conducted correlation analyses between the time series UV data and the considered parameters, revealing mutual relationships between these variables. UV radiation demonstrated a positive correlation with the SSN and F10.7 cm radio flux while showing a significant anticorrelation with the CR data. Furthermore, the mean daily time series of the variables underwent power spectral analyses to identify potential common periodicities. The spectral analyses showed several common periodicities in all the variables considered, such as ~410, 172, 165, and 66 days. Based on the correlations and spectral results, the study suggests that solar signals could have a direct or indirect impact on the observed solar UV radiation at a specific site. This finding has significant implications for our understanding of the factors that affect UV radiation.