摘要
Using high temporal resolution optical data obtained from three-wavelength all-sky imagers at Chinese Yellow River Station in the Arctic, together with the EISCAT Svalbard radar (ESR) and SuperDARN radars, we investigated the dayside pole- ward moving auroral forms (PMAFs) and the associated plasma features in the polar ionosphere under difibrent interplanetary magnetic field (1MF) conditions, between 0900 and 1010 UT on 22 December 2003. Simultaneous optical and ESR observations revealed that all PMAFs were clearly associated with pulsed particle precipitations. During northward IMF, particles can precipi- tate into lower altitudes and reach the ionospheric E-region, and there is a reverse convection cell associated with these PMAFs. This cell is one of the typical signatures of the dayside high-latitude (lobe) reconnection in the polar ionosphere. These results indicate that the PMAFs were associated with the high-latitude reconnection. During southward IMF, the PMAFs show larger lati- tudinal motion, indicating a longer mean lifetime, and the associated ionospheric features indicate that the PMAFs were generated by the dayside low-latitude reconnection.
Using high temporal resolution optical data obtained from three-wavelength all-sky imagers at Chinese Yellow River Station in the Arctic, together with the EISCAT Svalbard radar (ESR) and SuperDARN radars, we investigated the dayside pole- ward moving auroral forms (PMAFs) and the associated plasma features in the polar ionosphere under difibrent interplanetary magnetic field (1MF) conditions, between 0900 and 1010 UT on 22 December 2003. Simultaneous optical and ESR observations revealed that all PMAFs were clearly associated with pulsed particle precipitations. During northward IMF, particles can precipi- tate into lower altitudes and reach the ionospheric E-region, and there is a reverse convection cell associated with these PMAFs. This cell is one of the typical signatures of the dayside high-latitude (lobe) reconnection in the polar ionosphere. These results indicate that the PMAFs were associated with the high-latitude reconnection. During southward IMF, the PMAFs show larger lati- tudinal motion, indicating a longer mean lifetime, and the associated ionospheric features indicate that the PMAFs were generated by the dayside low-latitude reconnection.
基金
supported by the National Natural Science Foundation of China (Grant nos. 40974083, 41031064, 41104091,41104090, 41274149 and 41274164)
the Ocean Public Welfare Scientific Research Project of China (Grant no. 201005017)
the Polar Strategic Research Foundation of China (Grant nos. 20100202, 20100203 and 20120304)
the Polar Environment Comprehensive Investigation & Assessment Programs(Grant no. CHINARE 2012-02-03)