Multistatic meteor radar observations of two-dimensional horizontal MLT wind

Abstract. All-sky meteor radars have become a reliable and widely used tool to observe horizontal winds in the mesosphere and lower thermosphere (MLT) region. The horizontal winds estimated by conventional single-station radars are obtained after averaging all meteor detections based on the assumption of the homogeneity of the horizontal wind in the meteor detection area (approximately 200–300 km radius). In this study, to improve the horizontal winds, we apply a multistatic meteor radar system consisting of a monostatic meteor radar in Mengcheng (33.36° N, 116.49° E) and a bistatic remote receiver in Changfeng (31.98° N, 117.22° E), separated by approximately 167 km to increase the number of meteors by at least 70 % and provide two different viewing angles of the meteor echoes. The accuracy of the horizontal wind measurement depends on the meteor number in time and altitude intervals. Compared to typical monostatic meteor radar, our approach shows the feasibility of estimating the two-dimensional horizontal wind field. The technique allows us to estimate the mean horizontal wind and the gradient terms of the horizontal wind, moreover, the horizontal divergence, relative vorticity, stretching and shearing deformation of the wind field. We are confident that the improved horizontal wind parameters will contribute to improving the understanding of the dynamics in the MLT region.