Ampere force exerted by geomagnetic Sq currents and thermospheric pressure difference

Masahiko TAKEDA

Presentation information

Oral

Symbol P (Space and Planetary Sciences) » P-EM Solar-Terrestrial Sciences, Space Electromagnetism & Space Environment

[P-EM27] Physics and Chemistry in the Atmosphere and Ionosphere

Tue. May 26, 2015 11:00 AM - 12:45 PM A01 (APA HOTEL&RESORT TOKYO BAY MAKUHARI)

Convener:*Yuichi Otsuka(Solar-Terrestrial Environment Laboratory, Nagoya University), Takuya Tsugawa(National Institute of Information and Communications Technology), Seiji Kawamura(National Institute of Information and Communications Technology), Chair:Yoshihiro Tomikawa(National Institute of Polar Research), Yoshihiro Kakinami(School of Systems Engineering, Kochi University of Technology)

12:15 PM - 12:30 PM

View Presenter supplemental information

[PEM27-16] Ampere force exerted by geomagnetic Sq currents and thermospheric pressure difference

*Masahiko TAKEDA¹ (1.Data Analysis Center for Geomagnetism and Space Magnetism., Kyoto Univ.)

Keywords:geomagnetic daily variation, total current, Ampere force, thermospheric pressure difference, solar acivity

Relationship between Ampere force exerted by geomagnetic Sq currents and neutral pressure was examined. It was shown that the Ampere force around the Sq current vortex center is almost equal to the pressure difference between its maximum and minimum, and this balance is kept through the solar cycle. The lowest height of the pressure integration for best fit is 120km, which is reasonable considering the height profile. There was a seasonal variation that the pressure difference is smaller and larger in local summer and winter, respectively. This is consistent with the effects of magnetic field by inter-hemispheric field-aligned currents on geomagnetic Sq field.