Comparison of travelling ionospheric disturbance measurements with thermosphere/ionosphere model results

Abstract

Abstract.Comparisons of modeled and measured responses of the ionosphere to the passage of atmospheric gravity waves are made for data recorded by an ionosonde located at Almaty (76 • 55 E, 43 • 15 N) from June 2000 until May 2001. Temporal variations of the altitude (hmF) and electron content (NmF) of the F-layer peak are used for comparisons. A significant part of the observations showed well-defined wave structures on the hmF, NmF and other parameter variations observed throughout the entire nights. Both the modeling study and measurements showed that, as the F-layer is lifted by the positive surge in gravity wave, the electron content at the F-layer peak decreases, with the slab thickness being increased as well. Subsequently, the opposite happens as hmF falls below its equilibrium value. Some discrepancy between the model and experimental results related to the phase difference between hmF and NmF variations is revealed.

The observed compression and expansion of the F2 ionosphere as a major component of ionospheric variability

“…The stated relationship between these parameters described here is in full agreement with the previous experimental results of Ashkaliev et al . [], Yakovets et al . [], and Yakovets et al .…”

“…Many other examples of TIDs could be given but all show the same characteristic relationship between f o F 2 , h ′ F 2 , h m , h b , and y m as that described above and as reported, for example, by Ashkaliev et al . [].…”

“…Despite the long history of TID observation, the generic relationship between f o F 2 and h m (as well as virtual height) discussed in this paper has only occasionally been recognized [e.g., Vlasov et al ., ; Shiokawa et al ., ; Liu et al ., ] and the relationship of these parameters with the subpeak thickness y m , while previously reported [ Ashkaliev et al ., ; Yakovets et al ., , , , ; Pezzopane et al ., ], continues to remain little known in the ionospheric community.…”

Large-scale travelling atmospheric disturbances in the night ionosphere during the solar–terrestrial event of 23 May 2002

“…Kubota et al (2001) and occasionally commented on, e.g. Shiokawa et al (2002Shiokawa et al ( , 2003 and Ashkaliev et al (2003). The generality of this effect does not seem to have been widely recognized.…”

Growth and decay of a post-sunset equatorial anomaly at low latitudes: Control of E×B, neutral winds and daytime electrojet strength

“…In such cases meridional winds in association with E Â B drift, also seems to play seems to play a part especially in determining the crest of the anomaly. In addition, some of the post sunset hours IEC variations, showing large scale variations having periodicity of 4-6 h at different locations, which are difficult to explain simply by diffusion of plasma under E Â B drifts may also be caused by larges scale traveling ionospheric disturbances (TIDs), especially during the periods of magnetic disturbances, as reported by several authors, e.g., Aushev et al (2002); Ashkaliev et al (2003). It is well known that large scale TIDs are mainly generated during magnetic disturbances, which propagate equator ward.…”