instead of the drought scientists feared
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Farmers across Western Australia's wheatbelt watched rain fall through winter, defying months of stark drought warnings from national forecasters.
Meteorologists had forecast drought, citing a record-strength El Niño, the periodic warming of the central Pacific Ocean. Instead, paddocks turned green as an unprecedented climate anomaly delivered rain nobody predicted.
The paradox traces back to new research on El Niño's long-term intensity.
A landmark study published in the journal Science analysed 1,000 years of coral data. Findings showed El Niño events have grown nearly 40 per cent stronger since the pre-industrial era.[1]
The research appeared in Science, widely regarded as one of the world's most rigorous peer-reviewed journals. Lead author Julia Cole, a paleoclimatologist at the University of Michigan, headed the international team. Her team examined whether rising global temperatures were reshaping El Niño's long-term intensity.[1]
Coral-based measurements revealed a 36 per cent jump in El Niño strength since large-scale industrialisation began. Compared with the twentieth century alone, the increase measured roughly 16 per cent. Combined, these shifts pushed recent El Niño intensity nearly 40 per cent above pre-industrial levels.[3]
Corals record ocean chemistry much the way tree rings record successive growing seasons over centuries. Strontium-to-calcium ratios and oxygen isotopes preserve centuries of sea-surface temperature data. Scientists sampled these layers a millimetre at a time to reconstruct the record.[2]
The study spanned roughly 1,000 years, reaching back through medieval times to before 1850. That predates large-scale human greenhouse gas emissions by more than a century. Researchers therefore had a genuine pre-industrial baseline for comparison.[1]
Researchers sampled 13 coral colonies from the remote Galápagos Islands, including both living and long-dead fossil specimens. The Galápagos sits at the heart of El Niño's strongest ocean-temperature swings. That location made the corals an unusually sensitive natural recorder of the phenomenon.[6]
Each individual core provided a continuous chemical record spanning at least two decades of growth. By stacking overlapping cores, scientists reconstructed a near-continuous millennium-long timeline. This approach let them compare eras separated by hundreds of years directly.[2]
The pre-industrial baseline came from ancient corals predating widespread fossil fuel combustion and industrial emissions. Modern El Niño events consistently exceeded that historical range in strength. No period before 1850 matched the intensity recorded across the last four decades.[1]
The long baseline let scientists methodically rule out ordinary natural variability as the underlying cause. Volcanic activity and solar cycles failed to explain the scale of change. That left human-driven warming as the most plausible remaining explanation.[2]
Meanwhile, a separate but closely related event has gripped the tropical Pacific throughout this year. The Bureau of Meteorology declared El Niño active in mid-June, part of the El Niño-Southern Oscillation, or ENSO, cycle. Forecasters flagged it as among the strongest events since formal records began in 1950.[4]
Standard seasonal outlooks predicted a hot, dry spring across most of the eastern and southern country. Historically, moderate to strong El Niño events cut Australia's winter rainfall by roughly a third. Spring rainfall typically falls by a fifth, with summer effects far smaller.[8]
Instead, Australia is tracking toward its wettest El Niño year on record. National rainfall had already passed 400 millimetres by late winter, well above historical El Niño averages. Western Australia and the Northern Territory face a wet spring rather than the forecast drought.[5]
This mismatch raises hard questions for drought, water security and bushfire planning agencies nationwide. Water authorities, farm lenders and emergency services calibrated preparations around a dry-season forecast. Officials now face pressure to explain how confident outlooks diverged so sharply from outcomes.[5]
Scientists identify rising greenhouse gas concentrations as the primary driver behind this long-term shift. Fossil fuel emissions have warmed the tropical Pacific Ocean's surface layer for over a century. That warming appears to be sharpening the natural swings between El Niño and La Niña.[2]
The link troubles scientists because ENSO drives weather patterns far beyond the Pacific basin alone. Stronger El Niño events amplify droughts, floods, wildfires and food insecurity worldwide. A more volatile cycle therefore threatens communities with little direct connection to the ocean itself.[1]
Human activity appears to skew the ENSO cycle toward more frequent, more extreme El Niño phases. The cycle still swings toward La Niña, its cooler counterpart, but the amplitude has grown. Researchers describe a natural system now behaving well outside its historical range.[3]
The sudden jump in intensity signals a climate system still responding to decades of past emissions. Global greenhouse gas output remains far above levels compatible with a stable climate. Continued warming risks pushing El Niño intensity beyond even this year's extremes.[2]
A stronger ENSO cycle now threatens the very coral reefs that provided this historical record. Repeated marine heatwaves have already pushed global coral cover down to about a quarter of reef area. Scientists warn recovery windows between heat events keep shrinking.[7]
For Australian communities, an intensifying cycle complicates disaster preparedness and economic planning. Insurers already price flood and bushfire risk using historical El Niño patterns that are becoming outdated. Farmers, regional lenders and emergency planners now face growing uncertainty over which scenario to prepare for.[8]
First Nations land and fire managers face similar uncertainty across vast stretches of country. Cultural burning programs and seasonal calendars rely on predictable wet and dry patterns. An increasingly erratic cycle complicates decisions once guided by generations of observation.
The combined findings place fresh urgency on Australia's national climate policy and emissions reduction targets. Every fraction of a degree of warming appears to compound El Niño's extremes. Scientists say the current event offers a preview of a hotter, more volatile future.[6]
Two exceptional events now sit side by side. A 1,000-year coral record shows El Niño growing far stronger since industrialisation began. Australia's unpredictable rainfall this year shows what that intensified cycle looks like in practice.
Forecasting agencies got the direction of Australia's season wrong despite record confidence. That gap between forecast and outcome deserves closer scrutiny from policymakers and regulators. Communities cannot plan effectively around outlooks that diverge so sharply from reality.
The underlying science remains clear regardless of any single season's surprises. Warming oceans are reshaping one of Earth's most influential climate cycles. Governments and industries now carry the responsibility of preparing for greater volatility ahead.
1. El Niños More Intense Over Last 40 Years Than Previous 1,000 Years. University of Michigan announcement summarising the Science study's key findings.
2. Climate Change Is Strengthening El Niño, Coral Records Suggest. Peer-reviewed coverage detailing the study's methodology and intensification figures.
3. El Niño Events Are Becoming Stronger as the World Warms. News analysis comparing El Niño intensity across different historical baselines.
4. El Niño: What It Means for Australia's Climate. Official Bureau of Meteorology guidance on the current event's likely impacts.
5. Why Australia's Weather Is Seeing a Soaking While a Record El Niño Is Forming. Investigation into why rainfall diverged from seasonal drought forecasts.
6. Climate Change Is Supercharging El Niños, Coral Records Show. Science journalism explaining why the Galápagos coral record carries particular weight.
7. Heat Stress Is Harming Coral Reefs, Global Data Shows. Reporting on shrinking recovery windows for coral reefs amid repeated heat events.
8. El Niño in 2026 Could Be One of the Strongest on Record. Analysis of the historical relationship between El Niño strength and Australian rainfall decline.
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