This study correlates ionospheric parameters with the integrated solar radiation for an analysis of the delayed ionospheric response in order to confirm previous studies on the delay and to further specify variations of the delay (seasonal and spatial). Results also indicate the dependence on the geomagnetic activity as well as on the 11-year solar cycle. The results are important for the understanding of ionospheric processes and could be used for the validation of ionospheric models.

In this work, we studied the HILDCAA disturbance time effects in the TEC by analyzing local time and seasonal dependences, and the influences of the solar wind velocity on a sample of 10 intervals occurring in 2015 and 2016. The main results show great variability in the hourly distribution of the dTEC between one interval and another, seasonal behavior different from that presented by geomagnetic storms, and interestingly no relation between the dTEC disturbances and the magnitude of the HSS.

Based on our simulation results, both temperature change and meridional neutral wind could cause the 630.0 nm nightglow intensity to vary, while the latter is more effective. An unexpected aspect of the results is the non-monotonic dependence of the emission rate on temperature, featuring a turning point as the temperature changes. Our findings of these turning temperature tendencies can guide future modeling attempts to match the observed nightglow brightness intensities.