Atmosphere Ocean Interaction in the MJO and its Embedded Convective Disturbances

We report anomalies of surface fluxes of momentum, sensible heat flux, evaporation, and radiation over the intraseasonal Madden Julian Oscillation (MJO) using DYNAMO ship and buoy measurements in situ, and gridded surface flux products (based on satellites and reanalyses) over the Indian and Western Pacific Oceans. Surface flux anomalies are strongly correlated with convective activity as indicated by outgoing longwave radiation (OLR). Daily negative surface insolation anomalies of –100 W m^–2 are found beneath towering cumulus clouds. Simultaneous wind stress and evaporation anomalies likewise cool the ocean surface during times of convective activity. Sensible heat flux anomalies are smaller but more highly correlated to intraseasonal variability. Time-longitude plots demonstrate eastward-propagating surface flux anomalies associated with the MJO, and with equatorial Kelvin waves. We diagnose the relation between convective anomalies and surface fluxes, contrasting the Kelvin waves and the MJO, and contrasting anomalies over the Indian and Pacific Ocean.