Influences of CO₂ increase, solar cycle variation, and geomagnetic activity on airglow from 1960 to 2015

Variations of airglow intensity, Volume Emission Rate (VER), and VER peak height induced by the CO₂ increase, and by the F10.7 solar cycle variation and geomagnetic activity were investigated to quantitatively assess their influences on airglow. This study is an extension of a previous study by Huang (2016) covering a time period of 55 years from 1960 to 2015 and includes geomagnetic variability. Two airglow models, OHCD-90 and MACD-90, are used to simulate the induced variations of O(¹S) greenline, O₂(0,1) atmospheric band, and OH(8,3) airglow for this study. Overall, our results demonstrate that airglow intensity and the peak VER variations of the three airglow emissions are strongly correlated, and in phase, with the F10.7 solar cycle variation. In addition, there is a linear trend, be it increasing or decreasing, existing in the airglow intensities and VERs due to the CO₂ increase. On other hand, airglow VER peak heights are strongly correlated, and out of phase, with the Ap index variation of geomagnetic activity. The CO₂ increase acts to lower the VER peak heights of OH(8,3) airglow and O(¹S) greenline by 0.2 km in 55 years and it has no effect on the VER peak height of O₂(0,1) atmospheric band.