Research of the influence of strong meteorological disturbances in the Earth’s lower atmosphere on variations of ionospheric parameters in the Asian region of Russia

Chernigovskaya M.A.1, Kurkin V.I.1, Orlov I.I.1, Poddelsky I.N.2, Poddelsky A.I.2, Sharkov E.A.33
  1. Institute of Solar-Terrestrial Physics SB RAS, Irkutsk, Russia
  2. Institute of Cosmophysical Research and Radiowave Propagation, Far East Division, Russian Academy of Sciences, v. Paratunka, Kamchatka region, e-mail: drug@ikir.kamchatka.ru
  3. Institute of Space Research RAS, Moscow, Russia

The wave mechanism is one of the most effective mechanisms of interaction between the atmospheric layers
and of the influence of the lower atmospheric layers on the upper atmosphere and the ionosphere. This work relies
on the analysis of short-period temporal variations of ionospheric parameters to investigate a possibility that
strong meteorological disturbances in the Earth’s lower atmosphere are reflected in the ionospheric parameter
variations in a zone far removed from the source of the disturbance. Tropical cyclones (TC) may be a most
powerful potential source of impact from below. The analysis involves data on maximum observed frequencies
(MOF) of oblique sounding (OS) signals along the Norilsk–Irkutsk, Magadan–Irkutsk, and Khabarovsk–Irkutsk
paths in East Siberia and the Far East obtained at equinoxes (March, September) in 2005–2009 and in November
2005.
A frequency analysis has revealed time intervals with enhanced intensity of short-period oscillations which
may be interpreted as manifestations of large-scale traveling ionospheric disturbances (TIDs) whose sources were
internal gravity waves (IGWs) with periods of 1–5 hours. Based on a complex analysis of helio-geomagnetic,
ionospheric, and meteorological data in the regions under study as well as of data on tropical cyclones, we have
made an attempt at finding a link between a number of detected TIDs and the ionospheric responses to tropical
cyclones which were in their active phase in the north-west Pacific during the periods in question. A consid-
erable increase in the energy of short-period wave disturbances was observed along the Khabarovsk–Irkutsk,
Magadan–Irkutsk, and Norilsk–Irkutsk paths during active tropical cyclogenesis in September 2008–2009. The
intensity of the observed TIDs decreased as the midpoints of the OS paths moved westward away from the
potential IGW sources. Ionospheric responses to wave disturbance propagation from the same IGW sources
differ in the OS paths under analysis. The wave disturbance propagation velocities were estimated from the
delay in TID passage in the regions of the midpoints of the spaced-apart OS paths. Short-period TIDs can
also be observed at the spring equinox in March 2005–2009 under quiet helio-geomagnetic conditions and in the
absence of active tropical cyclones in the north-west Pacific, but their energy is much lower than during the
autumns of various years.
The study was supported by the RFBR grant № 09-05-00760.