Rainfall anomaly response to ENSO and IOD teleconnections in the CORDEX-SEA simulations

Abstract

Abstract This study aims to assess the relationships between rainfall anomalies in Southeast Asia region and ENSO-IOD teleconnections in the Coordinated Regional Climate Downscaling Experiment–Southeast Asia (CORDEX-SEA) multi-model simulations. The assessment process employed various statistical parameters, including standard deviation ratio, correlation, wavelet, and empirical orthogonal function (EOF) analysis. The method involved a statistical comparison of Niño3.4 index measured from the models to the observations, spatial correlation of simulated precipitation anomalies with Niño3.4 index measured from the observations and from the models, and correlation between the first leading principal component of Niño3.4 with rainfall time-series. The same procedures were applied for IOD index. ERA5 and GPCP rainfall, and COBE sea-surface temperature datasets were used as references of comparison. The results showed that SEA rainfall anomalies in most CORDEX-SEA models displayed a varied response to Niño3.4 and IOD index. NorESM1-d model followed by GFDL-b exhibited the highest similarity to references (ERA5 and GPCP) in capturing SEA rainfall-Niño3.4/IOD connectivity.