Interannual changes in spectral irradiance at UV wavelengths is one of sources of solar-driven decadal variability in the atmosphere and in particular in the stratosphere as most of these changes happen at UV wavelengths. In last recent years, it has been suggested that energetic electron precipitation (EEP) also contributes not only to alter the chemical composition of the middle atmosphere but also its dynamical variability through changes in stratospheric ozone. In this study we investigate the effects of the two forcings and their interactions. We employ 35-year long integrations of the atmospheric version of the Whole Atmosphere Community Climate Model version 5 with different idealized and stationary solar and geomagnetic forcing terms. Four experiments are carried out combining high (H) and low (L) solar radiative forcing and high (7) and low (3) EEP associated with geomagnetic activity: H7 (with high radiative forcing and high EEP), H3 (high/low), L7 (low/high), and L3 (low/low). We find that the extension, the seasonality, and the significance of the effects of these two forcing terms on the atmospheric variables like temperature, NOx, and ozone are dependent on the joint effects of both forcing terms. The effect of the impact on NOx, ozone and temperature was measured, on constant pressure levels, by means of a Monte Carlo test. Under minimum solar conditions EEP affects mainly the NOx field on constant pressure levels, even though vertical cross sections show statistically significant effects on temperature and ozone in the southern hemisphere during austral winter and the following spring. Under solar maximum condition the effect of EEP becomes important. Ozone depletion (augmentation) in the upper levels of the stratosphere due to more (less) NOx, produced by EEP, allows UV radiation to produce more (less) ozone in the lower levels of the stratosphere. Solar irradiance hence plays an important role in modulating the impact of geomagnetic activity on climate variables.