Fig. 6 | Nature Communications

Fig. 6

From: A model for super El Niños

Fig. 6

Evolution of Indo-Pacific climate anomalies during 2006. Time-longitude evolution of a sea surface height (SSH), b SST, and c outgoing longwave radiation (OLR) and surface zonal wind anomalies (vector, units: m s−1). All variables were averaged between 5°S and 5°N, except over the Indian Ocean—here, SST, SSH, and OLR anomalies were averaged from 10°S to the Equator, considering their strong equatorial asymmetry during IOD. We used daily resolution data that were low-pass Lanczos filtered to remove (weather) variations shorter than 30 days. IOD strong and robust positive OLR anomalies over the eastern equatorial Indian Ocean drive easterly anomalies over the Indian Ocean, as the Rossby wave response, and westerly anomalies over the Pacific, as the Kelvin wave response. Area-averaged anomalies over selected regions contrast the nature of ocean–atmosphere coupling in the Indian (d) and Pacific (e) oceans—the time series were further smoothed with a 31-day running mean. In d, DMI (dashed line) evolves tightly in step with equatorial Indian Ocean zonal wind (shaded curves, 80°E–100°E) and OLR anomalies (solid line, 80°E–110°E). In sharp contrast, over the equatorial Pacific (e), Nino3.4 SST (dashed line) anomalies significantly lag both equatorial zonal wind (shaded curve, 150°E–180) and OLR (solid line,150°E–180°E) anomalies. In d and e, zonal wind was divided by a factor of 2 and OLR by 25

Back to article page