Past and Future Modulation of the ENSO Teleconnection to Southeast Asian Rainfall by Interbasin Interactions

This is the authors' abstract. We don't add key points for this paper.

Decadal variations in the El Niño‐Southern Oscillation (ENSO)'s influence on Southeast Asian rainfall are modulated by variability in the mean state of atmospheric circulation and moisture anomalies in the Indo‐Pacific Warm Pool (IPWP). Variations in the mean state are characterized by a tripolar pattern in sea surface temperatures (SST) spanning the Indian Ocean, central IPWP, and western Pacific regions. Due to ENSO teleconnection asymmetry, Southeast Asian rainfall is more sensitive to La Niña than El Niño. During positive phases of the tripole pattern, the mean state is drier, with reduced vertical motion over mainland Southeast Asia suppressing La Niña anomalies. In negative phases, the mean state is wetter, with enhanced vertical motion amplifying La Niña anomalies. From 1980 to 2015, relative SST trends show a negative tripole pattern, strengthening the ENSO ‐ Southeast Asian rainfall relationship. However, future projections for 2050–2100 suggest a positive tripole pattern, predicting a weakening of this relationship by 2100.