Modulation of Air-Sea interaction on the MJO Propagation Through Maritime Continent

Recent studies have shown that during the MJO phase 4-5, when MJO propagates through the Maritime Continent, the MC islands experience a negative climatology rain anomaly. This indicates a suppression of the land-based convection.  A recent attempt to further investigate the role of air-sea interaction was conducted using the Coupled Ocean/Atmosphere Mesoscale Prediction System (COAMPS). The coupled system reveals that there was a redistribution of convection from land toward the surrounding shallow and deep marginal seas where the tropical inter-ocean exchange mixes the Pacific and Indian Ocean water. The tidal and freshwater barrier layer effects on the oceanic mixing processes are active in the MC region and this complicates the role of oceanic feedback on the MJO. We will discuss the COAMPS sensitivity experiments focusing on the CINDY/DAYNMO period to examine the MC ocean feedback on the MJO as well as the ocean interaction with the flow induced by the surrounding island topography and heterogeneous land surface.