Abstract Details

Name: Kammadhanam Chenna Reddy
Affiliation: Dept. of Astronomy, Osmania University, Hyderabad - 500 007
Conference ID: ASI2020_286
Title : Latitudinal asymmetry in vertical distribution of meteor decay time at North and South poles
Authors and Co-Authors : K Chenna Reddy^1, B Premkumar^1, P B Devika^2 & N J Mitchell^3 1. Department of Astronomy, Osmania University, Hyderabad, India - 500007 2. Dept. of Physics, Central University of Tamil Nadu, Thiruvarur - 610 005. 3. Department of Electronic & Electrical Engineering, Centre for Space, Atmospheric and Oceanic Science, University of Bath, United Kingdom
Abstract Type : Poster
Abstract Category : Sun and the Solar System
Abstract : The meteor decay time heights are strongly dependent on local atmospheric conditions in the mesospheric lower thermospheric (MLT)-region. In this study, we comparatively examine the seasonal variation of vertical distribution of meteor decay time at two identical radars of opposite geographical latitudes, Esrange (68^oN, 21^oE) and Rothera (68^oS, 68^oW). In order to understand the nature of decay time variations, the received signal power is categorised into two groups as weak and strong echoes and their monthly mean vertical profiles are constructed. It has been noticed that seasonally, the meteor decay time shows asymmetric distribution at opposite latitudes. From the mean decay time profiles, it has also been noticed that the decay time vertical profile turning altitude (i.e., inflection point) varies in the range of 82-87 km of altitudes at both the latitudes for weak and strong echoes. However, there is about 2 km difference in turning altitude between weak and strong echoes at both the latitudes. The turning altitude varies with seasons, higher the turning altitude is observed in summer and lower in winter. At both the latitudes, above the turning altitude, a steeper slopes are observed for strong echoes, except for summer season. However, at Rothera, unlike the strong echoes, a large scatter is found for weak echoes below 70 km of altitude, except in winter season. The probable reasons for such asymmetrical behaviour of meteor decay time across the latitudes are discussed.