Dynamical Downscaling for Assessment of the Climate in Ghana
Masaru Inatsu*1, Tsubasa Nakayama*1, Yoshie Maeda*2,*3,
and Hirotaka Matsuda*3,*4
*1Graduate School of Science, Hokkaido University, N10W8, Kita, Sapporo 060-0810, Japan
*2Japan Weather Association, 3-1-1 Higashi-Ikebukuro, Toshima, Tokyo 170-6055, Japan
*3Integrated Research System for Sustainability Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-8654, Japan
*4Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8561, Japan
Dynamical downscaling (DDS), in which a regional atmospheric model (RAM) experiment nested into coarser-resolution data provides a spatio-temporal fine dataset for a particular region, was performed to assess the present climate in Ghana. The DDS successfully evaluated realistic seasonal march and inter-annual variability in rainfall, in comparison with gauge and satellite observation. The DDS also indicated that land-lake and land-sea circulation interacted with the West African monsoon likely characterized the local climate in Ghana.
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