Horizontally resolved structures of radar backscatter from polar mesospheric layers

[摘要] The Leibniz-Institute of Atmospheric Physics in Kühlungsborn, Germany (IAP)installed a new powerful VHF radar on the North-Norwegian island Andøya(69.30° N, 16.04° E) from 2009 to 2011. The new MiddleAtmosphere Alomar Radar System (MAARSY) replaces the existing ALWIN radarwhich has been in continuous operation on Andøya for more than 10 yr.MAARSY is a monostatic radar operated at 53.5 MHz with an active phasedarray antenna consisting of 433 Yagi antennas each connected to its owntransceiver with independent control of frequency, phase and power of thetransmitted signal. This arrangement provides a very high flexibility of beamforming and beam steering. It allows classical beam swinging operation aswell as experiments with simultaneous multiple beams and the use of moderninterferometric applications for improved studies of the Arctic atmospherefrom the troposphere up to the lower thermosphere with high spatial-temporalresolution. The installation of the antenna was completed in August 2009. Aninitial expansion stage of 196 transceiver modules was installed in spring2010, upgraded to 343 transceiver modules in December 2010 and theinstallation of the radar was completed in spring 2011. Beside standardobservations of tropospheric winds and Polar Mesosphere Summer Echoes,multi-beam experiments using up to 91 beams quasi-simultaneously in themesosphere have been carried out using the different expansion stages of thesystem during campaigns in 2010 and 2011. These results provided a firstinsight into the horizontal variability of Polar Mesosphere Summer and WinterEchoes in an area of about 80 km by 80 km with time resolutions between 3and 9 min.

[学科分类] 电子、光学、磁材料