资源环境科技发展态势分析平台

We provide evidence that midlatitude postsunrise traveling ionospheric disturbances (TIDs) are comprised of electrified waves with an eastward propagation component. The post-sunrise gravity wave (GW) wind-induced dynamo action effectively generated periodic meridional polarization electric fields (PEFs), facilitating TID zonal propagation in a similar fashion as GW-driven neutral perturbations. A combination of near-simultaneous eastward and upward observations using the Millstone Hill incoherent scatter radar along with 2-dimensional total electron content maps allowed resolution of TID vertical and horizontal propagation as well as zonal ion drifts Veast (meridional PEFs). In multiple observations, Veast oscillated in the early morning during periods when TIDs exhibited downward phase progression, 30-60 min period, ∼140 m/s eastward speed, and 70 km vertical wavelength. Inside these TIDs, multiple flow vortexes occurred in a vertical-zonal plane spanning the ionospheric topside and bottomside. Subsequently, PEFs weakened after a few hours as TID horizontal wavefronts rotated clockwise.