ESR IPY Observations And Study On Polar Mesosphere Summer Echoes

Polar ionosphere is especially structured and coupled with magnetosphere via convection electric field, particle precipitation and field-aligned current. It plays an important role in the coupling processes among the solar wind, magnetosphere, ionosphere and thermosphere. Techniques for observing space provides more comprehensive and precise scientific data which accelerate people's knowledge of upper atmosphere. It is essential for understanding the plasma transportation and energy exchange between the magnetosphere and the ionsphere as well as their physical processes.In this dissertation, we introduce the morphology of polar ionosphere, the physical process in ionosphere, techniques for observing upper atmosphere, and PMSE phenomena. By thorough statistical analysis of EISCAT radar data during 2007~2008 in Svalbard (78°N,16°E), the averaged diurnal 2-D distributions of electron density, peak electron density, electron temperature, critical frequency and critical height are obtained and their variations within four seasons are compared. It is found that The activity of polar ionosphere mainly responses to solar radiation and particle precipitation. Furthermore, the results are compared with that forecasted by IRI model. The IRI model can not show magnetic noon phenomena at equinox and double-hump structure in winter. Comparatively, the IRI model matches the summer's result far better than the winter's.PMSE is the anomalously high power radar echoes from the mesosphere at high latitude in summer. Based on the charging theory of dust particles in dusty plasmas by P. K. Shukla, the equation of dust grain charging is formed. Derived from Boltzmann function and generalized Ohm's law, the formula of electric conductivity and dielectric constant of dust plasma in a weak electric field is obtained. Applying the theory of wave propagation in layered media, the reflection coefficient is presented and the profile of reflection changing with altitude is given, which arrive at a good agreement with the ECT-02 rocket-borne observation result. It indicates that the layered media theory is an important method to interpret PMSE phenomena.