A062-0025
Understanding the Impact of the Interactions between the Diurnal Cycle and Topography on the MJO in the Maritime Continent

Wednesday, 9 December 2020
Poster
Haochen Tan, Florida Institute of Technology, Melbourne, FL, United States, Pallav Ray, Florida Institute of Technology, Department of Marine and Environmental Systems, Melbourne, FL, United States, Jimy Dudhia, National Center for Atmospheric Research, Developmental Testbed Center, Boulder, CO, United States and Mitchell W Moncrieff, National Center for Atmospheric Research, Boulder, CO, United States
Abstract:
Past studies have shown that the diurnal cycle of solar radiation and topography may inhibit propagation of the Madden-Julian Oscillation (MJO) across the Maritime Continent (MC). However, to what extent the interactions between the diurnal cycle and topography influences the MJO is not known. This question is addressed by using Weather Research and Forecasting model (WRF) at cloud-permitting resolutions, and a set of experiments are designed for an MJO event from April 2009: Control (CTL), no-diurnal cycle (NO_DC), no-topography (No_Topo) and no-diurnal cycle plus no topography (No_DC_Topo). In the CTL simulation, the MJO signal is weakened when it enters the MC, with major convection stalling over Sumatra and Borneo islands. In No_DC, No_Topo, and No_DC_Topo experiments, the MJO propagation signal is intensified. We propose a factor separation method, that is well used in other areas of science, to quantify the role of the interactions between the diurnal cycle and topography on the MJO. Implications of the results are discussed.
<< Previous Abstract | Next Abstract >>