[P-EM04] Space Weather, Space Climate, and VarSITI

[PEM04-P15] Studies of the thermosphere and ionosphere with the EISCAT radar and whole atmosphere/ionosphere model: GAIA

*Hitoshi Fujiwara¹、Yasunobu Miyoshi²、Hidekatsu Jin³、Hiroyuki Shinagawa³、Satonori Nozawa⁴、Yasunobu Ogawa⁵、Ryuho Kataoka⁵、Huixin Liu² (1.Faculty of Science and Technology, Seikei University、2.Department of Earth and Planetary Sciences, Faculty of Sciences, Kyushu University、3.National Institute of Information and Communications Technology、4.Institute for Space-Earth Environment Research, Nagoya University、5.National Institute of Polar Research)

キーワード：thermosphere, ionosphere, GAIA, EISCAT

The thermosphere/ionosphere is the region that shows both the features of the atmosphere
and space. For example, the behaviors of the neutral and ionized gases characterize
the region through some collision and radiative processes. In addition, interactions between
neutral and ionized gases cause various phenomena in the thermosphere/ionosphere.
The thermosphere/ionosphere is also important for radio wave propagation and operation
of artificial satellites due to the atmospheric drag force. The accuracy of navigation systems
and life time of the satellites depend strongly on the thermospheric/ionospheric conditions.
In order to investigate the thermosphere/ionosphere, we have developed a numerical model
which includes all the atmospheric regions and ionosphere named GAIA. GAIA has reproduced
some thermospheric/ionospheric phenomena and revealed physical mechanisms in association with
the phenomena. In this study, we present a brief description of GAIA and show some recent
results. The collaboration with radar observations enables the GAIA simulations to be more
productive. We will show some European incoherent scatter (EISCAT) radar observations in
cooperation with GAIA simulations. The future plans of the EISCAT observations and GAIA
simulations will be also shown here.