Climate impacts of the El Niño–Southern Oscillation on Australia

Taschetto, A., McGregor, S., Dommenget, D., Gillett, Z., Nicholls, N., Sharmila, S., van Rensch, P., Verdon-Kidd, D., Boschat, G., Chung, C., Lieber, R., Abram, N., Allan, R., Allen, K., Ashcroft, L., Brown, J., Cai, W., Chand, S., Cowan, T., Dao, T. L., de Burgh-Day, C., Freund, M. B., Gallant, A., Gergis, J., Holbrook, N. J., Heidemann, H., Holgate, C., Hope, P., King, A., Lim, E.-P., McBride, J. L., McKay, R. C., Nguyen, H., Pepler, A., Perkins-Kirkpatrick, S., Power, S., Risbey, J. S., Santoso, A., Ummenhofer, C. C., Wang, G., & Zhang, X. (2025). Climate impacts of the El Niño–Southern Oscillation on Australia. Nature Reviews Earth & Environment, 1–21. https://doi.org/10.1038/s43017-025-00747-x

(Top) Multidecadal variability in the teleconnection, illustrated as the 14-year sliding correlation between September to November (SON) Niño3.4 and east Australian rainfall (blue line) and Tmax (red line). Thick portions of the lines show statistically significant correlation coefficients at the 90% confidence level. The Interdecadal Pacific Oscillation Tripole Index (TPI) filtered time series is overlaid (dotted line; positive and negative phases shaded yellow and grey, respectively). Australian Gridded Climate Data (AGCD) rainfall and HadISST data from 1900 to 2023. AGCD Tmax data available from 1910 to 2023. (bottom) Combined influence of ENSO, Indian Ocean Dipole (IOD), and Southern Annular Mode (SAM) on east Australian precipitation depicted by the time series of climate modes of variability and precipitation averaged over the Murray Darling Basin (MDB; line). East Australia (EA; yellow) and MDB (brown) regions are represented on the top-right map in the lower panel. [Adapted from Taschetto et al. 2025]

El Niño–Southern Oscillation (ENSO) profoundly affects Australian weather, climate, ecosystems and socio-economic sectors. In this Review, we summarize the advances in understanding the ENSO–Australian climate relationship, detailing the complexity beyond the traditional assumptions of El Niño-dry and La Niña-wet patterns, including mechanisms and impacts. The influence of ENSO is most coherent during austral spring, explaining about a quarter of rainfall variability over large parts of eastern Australia. La Niña typically exerts more robust rainfall changes than El Niño, and the Central Pacific El Niño has greater impacts than Eastern Pacific events. These effects are amplified by prolonged ENSO episodes and modulated by land–atmosphere feedback, surrounding sea surface temperatures, local processes and interactions with other climate modes, including multidecadal variability. El Niño-related drying generally worsens when co-occurring with positive Indian Ocean Dipole (IOD) and/or negative Southern Annular Mode (SAM), whereas La Niña rainfall intensifies with negative IOD and/or positive SAM.