Is climate change making El Niño stronger?

The IPCC concludes there is no clear trend in El Niño strength over the instrumental record. However, a 2023 study suggests extreme El Niño events may double in frequency under 2C warming. What IS clear: El Niño impacts are worse because climate change has raised the baseline — hotter heat waves, heavier rainfall, more severe droughts.

Does El Niño cause global warming?

El Niño does not cause long-term global warming, but it causes year-to-year temperature spikes by releasing stored ocean heat into the atmosphere. El Niño years are typically 0.1-0.2C warmer than the surrounding years. The combination of El Niño and human-caused warming is why 2023, 2024, and potentially 2026 set global temperature records.

El Niño vs Climate Change — Are They Making Each Other Worse?

The Question Everyone Asks

After three Super El Niño-level events in 25 years (1997-98, 2015-16, 2023-24) and a potential fourth in 2026, the question is unavoidable: is climate change making El Niño events stronger or more frequent?

The short answer from the IPCC: the evidence is not yet conclusive, but the trend is concerning and the impacts are certainly worse.

What the Science Says

Are El Niños Getting Stronger?

The IPCC Sixth Assessment Report (AR6) concludes there is no clear trend in El Niño amplitude over the instrumental record (roughly 1870-present). The 1997-98 and 2015-16 events were exceptionally strong, but so was the 1877-78 event. The paleoclimate record (coral proxies, tree rings) shows Super El Niños occurred long before industrial-era warming.

However, a 2023 study in Nature Climate Change found that the frequency of extreme El Niño events may double under 2°C warming — from roughly once every 20 years to once every 10 years. The mechanism: faster warming in the eastern equatorial Pacific creates conditions more favorable to strong El Niño development.

Are the Impacts Getting Worse?

This is the clearer link. Even if El Niño itself is not changing, its impacts are amplified by climate change:

Heat: El Niño releases heat from the ocean to the atmosphere. With a warmer baseline, El Niño years now routinely set global temperature records. 2023 (El Niño year) was the hottest year in recorded history. 2024 broke that record. 2026 may break both.
Rainfall: A warmer atmosphere holds more moisture. When El Niño steers storms toward California or Peru, those storms now carry 7% more water per 1°C of warming. The same storm delivers more flood risk than it would have 50 years ago.
Drought: Higher baseline temperatures increase evaporation. When El Niño brings drought to Australia or Southeast Asia, the drought is more severe than the same El Niño would have caused in a cooler climate.
Wildfire: El Niño drought + climate change heat = longer fire seasons and more extreme fire behavior.

What About La Niña?

There is stronger evidence that climate change is affecting La Niña. A 2022 study found that the frequency of multi-year La Niña events has increased, possibly due to faster warming in the western Pacific warm pool. The 2021-2023 triple-dip La Niña may be a preview.

The "Hot Spot" Problem

Climate models disagree on how ENSO will change. Some project more extreme El Niños. Others project no change. The eastern equatorial Pacific is a notoriously difficult region for climate models — it has not warmed as fast as models predict (the "cold tongue" problem), which means model projections of future ENSO carry high uncertainty.

What Is Clear

Three things are well-established:

Global temperatures during El Niño years are higher than they would be without climate change.
El Niño impacts (floods, droughts, fires) are more damaging because climate change has made the baseline more extreme.
Whether or not El Niño itself changes, its consequences will intensify as the planet continues warming.