Sensitivity to domain size of mid-latitude summer simulations with a regional climate model

摘要: The issue of Regional Climate Model (RCM) domain size is studied here by using a perfect-model approach, also known as the Big-Brother experiment. It that control exerted lateral boundary conditions (LBC) on nested simulations increases when reducing size. large-scale component simulation forced LBC influences small-scale features develop along flow. Small-scale transient eddies need space and time to sufficiently however, small domains can impede their development. Our tests performed over eastern North America in summer reveal are systematically underestimated entire domain, even for large 140 grid points. This result differs from obtained winter where scales were mainly west (inflow) side domain. difference due circulation regime Eastern Canada, which characterized weak variable flow summer, but strong westerly winter. For both seasons, transient-eddy amplitudes at higher levels, this problem less severe summer. Overall model more skilful regenerating than comparable sizes, be related weaker stronger physical processes occurring season.