Effects of mesoscale gravity waves on sporadic E simulated by a one-dimensional dynamic model

In addition to being driven by tidal winds, the sporadic E (E_s) layers are modulated by gravity waves (GWs), although the effects are not yet comprehensively understood. In this article, we discuss the effects of mesoscale GWs on the E_s layers determined by using a newly developed model, MISE-1D (one-dimensional Model of Ionospheric Sporadic E), with low numerical dissipation and high resolution. Driven by the wind fields resolved by the high-resolution version of the Whole Atmosphere Community Climate Model with thermosphere and ionosphere extension (WACCM-X), the MISE-1D simulation revealed that GWs significantly influence the evolution of the E_s layer above 100 km but have a very limited effect at lower altitudes. The effects of GWs are diverse and complex, generally including the generation of fluctuating wavelike structures on the E_s layer with frequencies similar to those of the GWs. The mesoscale GWs can also cause increases in the density of E_s layers, or they can disperse or diffuse the E_s layers and increase their thickness. In addition, the presence of GWs is a key factor in sustaining the E_s layers in some cases.