Comparison of seasonal and longitudinal variation of daytime MSTID activity using GPS observation and GAIA simulations

Abstract The total electron content (TEC) data derived from the GAIA (Ground-to-topside model of Atmosphere Ionosphere for Aeronomy) is used to study seasonal and longitudinal variation occurrence medium-scale traveling ionospheric disturbances (MSTIDs) during daytime (09:00–15:00 LT) year 2011 at eight locations in northern southern hemispheres, results are compared with ground-based Global Positioning System (GPS)-TEC. To derive TEC variations caused by MSTIDs (GPS) data, we obtained detrended subtracting 2-h (1-h) running average TEC, calculated standard deviation 2 h (1 h). MSTID activity was defined as a ratio averaged TEC. Both simulation GPS observations show that activities hemisphere (NH SH) higher winter than other seasons. From simulation, amplitude meridional wind variations, which could be representative gravity waves (GWs), shows two peaks summer. peak coincides MSTIDs, indicating high GW responsible activity. On hand, does not increase This because GWs thermosphere propagate poleward summer, equatorward winter, equatorward-propagating cause large plasma density perturbations poleward-propagating GWs. Longitudinal seen both hemispheres. NH over Japan USA, SH highest South America. In nutshell, can successfully reproduce MSTIDs. confirms propagation direction control noted variation. middle lower atmosphere