On the geomagnetic and ionospheric responses to an intense storm associated with weak IMF Bz and high solar wind dynamic pressure |
| |
Authors: | Victor U Chukwuma |
| |
Institution: | (1) Department of Physics, Olabisi Onabanjo University, Ago-Iwoye, Nigeria |
| |
Abstract: | A study of the geomagnetic storm of July 13–14, 1982, and its ionospheric response is presented using the low-latitude magnetic
index, Dst, and interpreted using solar wind interplanetary data: proton number density, solar wind flow speed, interplanetary magnetic
field southward component B
Z
, and solar wind dynamic pressure. The F2 region structure response to the geomagnetic storm was studied using foF2 data obtained during the storm from a network of various ionosonde stations. Our results appear to show simultaneous abrupt
depletion of foF2 that occurred at all latitudes in both the East Asian and African/European longitudinal zone during the period: 18:00–19:00
UT on July 13 and is as result of an abrupt increase in the dynamic pressure between 16:00 and 17:00 UT. The dynamic pressure
increased from 3.21 to 28.07 nPa within an hour. The aforementioned abrupt depletion of foF2 simultaneously resulted in an intense negative storm with peak depletion of foF2 at about 19:00 at all the stations in the East Asian longitudinal zone. In the African/European longitudinal zone, this simultaneous
abrupt depletion of foF2 resulted in intense negative storm that occurred simultaneously at the low latitude stations with peak depletion at about
20:00 UT on July 13, while the resulting negative storm at the mid latitude stations recorded peak depletion of foF2 simultaneously at about 2:00 UT on July 14. The present results indicate that most of the stations in the three longitudinal
zones showed some level of simultaneity in the depletion of foF2 between 18:00 UT on July 13 and 2:00 UT on July 14. The depletion of foF2 during the main phase of the storm was especially strongly dependent on the solar wind dynamic pressure. |
| |
Keywords: | geomagnetic storm solar wind solar wind dynamic pressure IMF B Z ionospheric storm |
本文献已被 SpringerLink 等数据库收录! |
|