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ISSN Печать: 0040-2508
ISSN Онлайн: 1943-6009
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SEASONAL EVOLUTION OF VERTICAL PROFILE OF PRECIPITABLE WATER CONTENT AND CLOUD-BASED ATTENUATION AT EHF BAND OVER A TROPICAL LOCATION USING GBMRR
Краткое описание
The seasonal evolution of vertical profiles of precipitable liquid water (PLWC) was examined in Akure in the Southwestern part of Nigeria during the onset months (OM), monsoon months (MM), and cessation months (CM). Rain rate (R) and PLWC were obtained from a ground-based K-band micro rain radar (GBMRR) sited at the Department of Physics, Federal University of Technology, Akure, Nigeria in the year 2018. The GBMRR data used are scaled vertically from 160 to 4800 m height at 30 range gates. A vertical trend PLWC has been based on the diurnal, seasonal, and monthly analysis. A cloud-based attenuation derived from attenuation along the path obtained from the K-band based on the relation with PLWC at K-V band frequencies were also analyzed using the Rayleigh approximation method. The results show that higher PLWC values with larger droplets are prevalent during the OM and CM, whereas lower values of PLWC are present in larger numbers during MM. This is attributed to the convective nature that is associated with the OM and CM. MM period is dominated by the stratiform rain type. Further results in total attenuation due to the cloud revealed that there is an increase in the attenuation as the frequency increases with higher values at the lower heights. Findings from this work would help to assess and mitigate the impact of cloud-based attenuation dynamics on the satellite communication systems link over the study area.
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