EL-NINO SOUTHERN OSCILLATION AND MADDEN-JULIAN (30-60 DAY) OSCILLATIONS DURING 1981-1982

An important issue in understanding the low-frequency oscillations of the atmosphere and the ocean-atmosphere system concerns the role of transients during individual events. This question is examined from an observational point of view for the period from September 1981 to April 1982, which includes the transitional phase of the 1982-1983 El Nino/Southern Oscillation (ENSO) cycle, as well as six Madden-Julian (30-60 day) oscillations (MJO). For the developing ENSO, it is shown that interannual transitions in the anomalous atmospheric circulation and in the sea surface temperatures in the western-central Pacific coincide with the passage of strong MJOs from the Indian to Pacific oceans. For a MJO during December 1981, evidence is provided that the shift of convection from the eastern Indian Ocean to the western Pacific Ocean involves transients having periods around 10 days. The role of transients is discussed from the perspective of these interannual and intraseasonal modes.