Damping of large-scale traveling ionospheric disturbances detected with GPS networks during the geomagnetic storm

Physics – Space Physics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

10

Ionosphere: Ionosphere/Atmosphere Interactions (0335), Ionosphere: Midlatitude Ionosphere, Ionosphere: Ionospheric Irregularities, Ionosphere: Ionosphere/Magnetosphere Interactions (2736)

Scientific paper

Large-scale traveling ionospheric disturbances (LSTIDs) during the geomagnetic storm on 22 September 1999 were studied using total electron content (TEC) data from the GPS Earth Observation Network (GEONET) in Japan, International GPS Service (IGS), and Continuously Operating Reference Stations (CORS) in the United States. The damping rates of the LSTIDs were precisely derived in several local time sectors and were found to depend on values of the background TEC. This indicates that the dominant physical mechanism of the LSTIDs' damping is the ion-drag effect by the background ionosphere. The high-resolution TEC data from GEONET revealed that two successive LSTIDs were damped significantly as they traveled equatorward in the dawn sector. The ratio of the perturbation component of TEC to the background component (ΔI/I0) decreased exponentially with the damping rate of 0.89/1000 km and 0.77/1000 km. We studied also the amplitude of ΔI/I0 at high latitudes using IGS data and found that the damping rates of LSTIDs at high latitudes tended to be smaller than those at midlatitudes. Global TEC observations during this geomagnetic storm by the IGS and CORS networks detected that several LSTIDs propagated also equatorward in the afternoon sector and in the night sector. The LSTIDs in the afternoon sector were most damped with the damping rate of 1.04/1000 km, which corresponds to the e-folding length of 961 km. The damping rate of LSTIDs in the night sector was found to be small. The LSTIDs had a tendency to be damped rapidly in the regions where background TEC was large. This dependence of the damping rate on latitude and local time indicates that this intense damping of LSTIDs was caused mainly by the ion-drag effect that is proportional to the ion collision frequency. The relation between the damping rates and the background TEC derived from the observation are consistent with those estimated with a theoretical calculation of the gravity wave damping by the ion-drag effect. The worldwide distribution of GPS receivers enabled us to estimate the longitudinal extent of these LSTIDs. The zonal width of LSTIDs in the dawn sector was narrower than 45° in longitude (2,900 km) around 55°N and wider than 20° in longitude (1,800 km) around 40°N. These widths were narrower than those reported in previous studies.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Damping of large-scale traveling ionospheric disturbances detected with GPS networks during the geomagnetic storm does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Damping of large-scale traveling ionospheric disturbances detected with GPS networks during the geomagnetic storm, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Damping of large-scale traveling ionospheric disturbances detected with GPS networks during the geomagnetic storm will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1005197

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.