AI Governance
Data Centers
Drones
Climate
Privacy
2026 Maine Senate
Bob Dylan
Corals Reveal Stronger El Niño Extremes
Coverage from Scientific American, Gizmodo, and others
A Science study led by University of Michigan paleoclimatologist Julia Cole uses fossil and modern Galápagos corals to reconstruct roughly 900 to 1,000 years of Eastern Pacific El Niño variability.
It estimates that recent events were about 36% to 40% stronger than preindustrial events and that natural forcings alone do not reproduce the observed shift, linking the change to a warmer climate while stopping short of formal statistical attribution. Stronger El Niños could increase the risks of rainfall extremes, drought, wildfire, marine heat, ecological damage and food insecurity, although the mechanisms and future trajectory remain uncertain.
If you read one thing
It provides the clearest broad overview of the millennium-long coral record, the reported intensification, and the central attribution dispute.
The counter-case
It presents the strongest available case that simulations and coral evidence link unusually strong recent El Niños to fossil-fuel warming.
Latest development
As the Story So Far driver, it clarifies that the striking coral result remains contested and requires additional evidence before establishing changed ENSO dynamics.
Recent El Niño intensification
Galápagos coral reconstructions spanning roughly 900 to 1,000 years indicate that recent eastern-Pacific El Niño variability is unusually strong—about 36% to 40% above preindustrial levels and about 16% above 20th-century levels. The increase emerged during the industrial era, with especially large events appearing since the 1980s.
Warming attribution is supported but not definitive
Simulations using volcanic and solar variability did not reproduce the observed intensification, and the eastern-Pacific pattern is consistent with warming-related mechanisms such as greater tropical-Pacific stratification. However, the study lacks formal statistical attribution, leaving human-caused warming as a strong but provisional explanation.
Interpretation and future trajectory remain contested
Some researchers argue that the coral signal conflicts with declining El Niño-related variability in recent Galápagos instrumental observations and may reflect a warmer background ocean rather than altered ENSO dynamics. The evidence also does not establish whether continued warming will strengthen El Niño further, since warming could eventually reduce the east-west temperature contrast that drives the cycle.
16%
increase in El Niño strength
“El Niño events are more than 36% stronger than they were before the industrial age began in the mid-1800s, with a 16% increase in the past 40 years, according to the study published in Science.”
19th century
onset period for the observed shift toward stronger El Niño events
“Their analysis found a gradual shift from weaker events to stronger ones after widespread fossil-fuel use began in the 19th century.”
1000 to 1850
preindustrial period used to assess El Niño cycle stability
“The record shows that El Niño cycles were relatively stable during the preindustrial period from 1000 to 1850. Sea surface temperatures became more variable during a transitional period from 1850 to the 1980s, before large spikes began with the first super El Niño in 1982-83.”
1850 to the 1980s
transitional period of increasing sea-surface-temperature variability
“The record shows that El Niño cycles were relatively stable during the preindustrial period from 1000 to 1850. Sea surface temperatures became more variable during a transitional period from 1850 to the 1980s, before large spikes began with the first super El Niño in 1982-83.”
1982-83
onset of large El Niño variability spikes with the first super El Niño
“The record shows that El Niño cycles were relatively stable during the preindustrial period from 1000 to 1850. Sea surface temperatures became more variable during a transitional period from 1850 to the 1980s, before large spikes began with the first super El Niño in 1982-83.”
Contested Issue
Does the Galápagos coral record demonstrate that El Niño variability itself has intensified, or does it primarily reflect broader greenhouse-gas-driven warming?
Multiple reports interpret the coral reconstruction and natural-forcing model tests as evidence that recent Eastern Pacific El Niño events have become unusually strong because of human-caused warming. Quoted outside scientists dispute whether the record isolates a change in ENSO dynamics, citing declining recent instrumental variability near the Galápagos and the possibility that a warmer background ocean makes anomalies appear larger without changing the underlying oscillation.
ENSO-dynamics intensification
The coral reconstruction shows unusually strong recent Eastern Pacific El Niño variability, and the failure of natural-forcing simulations to reproduce the shift supports greenhouse-gas warming as the most plausible explanation.
Background-warming interpretation
The coral signal may primarily reflect greenhouse-gas-driven warming of the background ocean rather than a change in El Niño dynamics, and recent instrumental observations near the Galápagos are described as showing declining El Niño-related variability.
Coral evidence more clearly challenges standard ENSO assessments, but replication is still needed
New analysis frames the coral reconstruction as a challenge to the IPCC’s earlier assessment that ENSO variability shows no systematic change, while highlighting that the record may reflect a warmer background ocean rather than altered El Niño dynamics. Independent paleoclimate records are still needed to establish the finding conclusively.
Previously
A Science study led by University of Michigan paleoclimatologist Julia Cole uses fossil and living Galápagos corals to reconstruct roughly 900 to 1,000 years of eastern Pacific temperatures and El Niño behavior. It estimates that recent El Niño events are about 36% stronger than preindustrial events and about 16% stronger than those of the 20th century, with the increase emerging during the industrial era. The findings suggest warming may be amplifying a climate pattern linked to more severe heat, drought, flooding, wildfire and ecological disruption, although the strength of the attribution and the outlook for future intensification remain debated.
The interpretation shifts modestly toward greenhouse-gas warming as the leading explanation for stronger recent El Niños, while retaining uncertainty over formal attribution and future trends. The update also introduces ocean stratification as a possible mechanism and slightly revises the estimated increase.