Response of the Earth’s Ionosphere to Solar Activity during Minimum, Moderate and Maximum Conditions

by Anil K. Das, Lisy M. Thomas, P. Thirupathaiah

Published: January 15, 2026 • DOI: 10.51584/IJRIAS.2025.10120047

Abstract

The response of Earth’s ionosphere to the solar radiation during minimum, moderate and maximum solar activity conditions is studied using the International Reference Ionosphere (IRI-2016) model during the solar cycle 24. The altitude profiles of ion densities (O2+, NO+, N+, O+), electron density (Ne), electron temperature (Te) and ion temperature (Ti) are obtained from the IRI-2016 model on 4 January 2020 (F10.7 = 69.8, minimum), 4 January 2012 (F10.7 = 131.6, moderate) and 4 January 2014 (F10.7 = 253.3, maximum) at 45o latitude and 180o longitude in both the hemispheres for 12 noon local time from 60 km to 500 km altitude. It is found that the ion densities and electron density show a significant variation above 200km during minimum, moderate and maximum solar activity conditions, whereas below 200km the variation is more or less same. The electron temperature shows a significant variation above 300km, whereas below 300km the variation is more or less same. The ion temperature shows a significant variation between 150km and 450km, whereas below 150km and above 450km the variation is more or less same. It is also found that the values of densities of O2+, N+, O+ and electron are higher at 45oN than 45oS at 100-200km, 300-400km, above 150km, and above 150km, respectively, at other altitudes these values are higher at 45oS than 45oN. The values of NO+ density, Te and Ti are higher at 45oS than 45oN at almost all altitudes.