Investigation of the Potential Changes in Ionospheric Patterns Due to Climate Variability

Abstract

This study examines the impact of ENSO-related climate variability on ionospheric TEC and scintillation using GNSS data from Bogotá, Antananarivo, and Baie-Comeau. The analysis contrasts a La Niña event (2020/21) with a strong El Niño event (2023/24), focusing on climate induced ionospheric changes under similar solar and geomagnetic conditions. Findings indicate that TEC rose by 45–108% during El Niño at all sites, with ENSO accounting for 17–27% of TEC variance post solar flux adjustment, while scintillation intensity increased by 25–40%. COSMIC 2 temperature data show enhanced tropospheric and lower-stratospheric disturbances during El Niño, indicating gravity wave-mediated coupling as a key mechanism. The results underscore ENSO's substantial influence on ionospheric dynamics across various latitudes, represent the pioneering systematic ENSO-ionosphere analysis for the African equatorial region, and emphasize significant consequences for GNSS-reliant applications, where TEC variability linked to ENSO may lead to meter-level positioning inaccuracies.