Impact of March North Atlantic Oscillation on Indian Ocean Dipole: role of air–sea interaction over the Western North Pacific

Abstract We investigated the relationship between North Atlantic Oscillation (NAO) and Indian Ocean Dipole (IOD), which has remained unknown to date. Reanalysis data linear baroclinic model experiments were employed in our study. The results showed significant correlation March NAO boreal summer autumn IOD, independent of El Niño–Southern signal, verified by partial analysis. Air–sea interaction over western Pacific (WNP) is a aspect physical mechanism through affects subsequent IOD. A strong positive induces equivalent barotropic cyclonic circulation WNP steady Rossby wave, accompanied local tripole sea surface temperature (SST) anomaly pattern. Facilitated air–sea feedback, low-level associated precipitation anomalies persist from early spring shift equatorward. During May–June, anomalous cyclone strengthens southeasterly wind enhances cooling off Sumatra–Java meridional circulation. Such ascends descends tropical southeastern Maritime Continent. Subsequently, wind–evaporation–SST wind–thermocline–SST feedback contribute IOD development. diagnosis ocean mixed-layer heat budget indicated that dynamic process with contributes more development than does atmospheric thermal forcing. Determining influence on considered useful advancing seasonal prediction