What do tropical Pacific warming trends mean for Australia’s future climate?
Every few years, Australians brace for the swing between potential drought and floods: the fingerprint of El Niño and La Niña. These are driven by sea surface temperature patterns in the tropical Pacific Ocean, and understanding how those patterns will change in the future is one of the most important questions in Australian climate science.
ACCESS models are helping scientists investigate warming patterns in the tropical Pacific Ocean, trends that impact Australia’s possible climate futures.
Both climate models and observations agree that sea surface temperatures in the Pacific are rising, but there is disagreement on the spatial pattern of this warming. Observations since the 1980s show faster warming in the west Pacific, pointing to a wetter, La Niña-like future. Over the same period, climate models including ACCESS-ESM1.5 and ACCESS-CM2 predict faster warming in the east Pacific, indicating a drier, El Niño-like future.
A team of researchers from the Bureau of Meteorology and the NESP Climate Systems Hub is tackling a puzzling question: why do climate models and real-world observations show different warming patterns in the tropical Pacific over recent decades, and what does this mean for Australia?
This visualisation compares the rate of sea surface temperature warming for observations and climate models.
In the video above, climate scientist Christine Chung walks through these two possible futures and what they mean for droughts, floods, agriculture, and communities across Australia. As she explains, “closing the gap between modelled and observed warming is critical to building climate projections we can trust, so we don’t enter unprepared into uncharted futures.”
This video is the first completed project from ACCESS-NRI’s Expression of Interest: 3D visualisation, launched in 2025, which aimed at creating visualisations and stories to promote the climate research that uses the climate models co-developed and maintained by ACCESS-NRI.
This project was a visual collaboration between the National Environmental Science Program (NESP) Climate Systems Hub and the Bureau of Meteorology researchers, ACCESS-NRI’s Model and Diagnostics (MED) team and the communication teams at ACCESS-NRI and NESP.
The research itself is part of the Uncharted Futures: Pacific Trends project, funded by the National Environmental Science Program (NESP), and contributes to the broader Uncharted Climate Futures initiative.
The striking visualisations used in the video were created by Owen Kaluza, visualisation specialist from ACCESS-NRI’s MED team, drawing on observational data alongside outputs from multiple global climate models, including Australia’s own ACCESS models ACCESS-ESM1.5 and ACCESS-CM2.
ACCESS-NRI is enabled by the Australian Government through the National Collaborative Research Infrastructure Strategy (NCRIS)
Read more about the Uncharted Climate Futures Project
CREDITS
Researchers: Christine Chung (interviewee), Zoe Gillett, Ghyslaine Boschat and Sugata Narsey (Bureau of Meteorology, NESP Uncharted Futures project)
Visualisation: Owen Kaluza (ACCESS-NRI)
Editing, narration and communications: Corey Hanrahan (voiceover) and Natalia Bateman (ACCESS-NRI)
Data and project management: Felicity Chun, Rhaegar Zeng and Romain Beucher (ACCESS-NRI)
Other assets (public domain and/or creative commons)
Figure Earth Systems: World Ocean Review 1, maribus gGmbH, Hamburg 2010, worldoceanreview.com
Stock videos from iStock.com: Chris Manning, crbellette, CINETOPIA, woody_james, ivz, Eduard Figueres
ERSST: Huang, B., Peter W. Thorne, et. al, 2017: Extended Reconstructed Sea Surface Temperature version 5 (ERSSTv5), Upgrades, validations, and intercomparisons. Journal of Climate, doi: 10.1175/JCLI-D-16-0836.1
AGCD: Evans, A., Jones, D., Smalley, R., & Lellyett, S. (2020). An enhanced gridded rainfall analysis scheme for Australia. Bureau Research Report-41, Melbourne, Australia.
Real time cloud dataset sourced from public NOAA data https://sos.noaa.gov/catalog/datasets/clouds-real-time/ developed by NOAA based on GOES, Himawari, Meteosat, JPSS, Suomi-NPP satellite data.
We thank the climate modelling groups for producing and making their model output available, the Earth System Grid Federation (ESGF) for archiving the data and providing access, and the multiple funding agencies that support CMIP6 and ESGF.