The El Niño weather phenomenon has triggered unprecedented sea surface temperatures in the Pacific Ocean, pushing global marine temperatures to historic highs for September according to the European observatory Copernicus.
Record-Breaking Temperatures Across the Tropical Pacific
Sea surface temperatures outside polar regions reached a global average of 21.05°C in September, breaking the previous monthly record of 20.92°C set in September 2023. Within the equatorial Pacific, the benchmark Niño 3.4 region hit an absolute record of 29.70°C. This surpassed peak values from previous intense El Niño episodes in 1982-1983, 1997-1998, and 2015-2016.
The Japan Meteorological Agency (JMA) announced that El Niño intensified with sea temperatures reaching 4.0°C above normal in the Pacific reference zone, exceeding the previous record anomaly of +3.6°C established in December 1997. However, Copernicus noted that climatologists are still working to separate the immediate El Niño effect from the broader, long-term trend of ocean warming caused by human-induced climate change.
Global Climate Pressures and the 1.5°C Threshold
Global surface temperatures for last month marked the second-warmest September on record, sitting 1.63°C above pre-industrial levels. This represents the second month where global temperatures have exceeded the 1.5°C warming threshold established under the Paris Agreement. While officially crossing this limit requires multi-year averages, scientists and United Nations officials view its eventual breach as unavoidable.
Meanwhile, the article cites climatologist James Edward Hansen, who warned that El Niño will generate widespread planetary problems rather than localized disruptions.
Agricultural Strain and Regional Droughts
The climatic shift has driven severe dry conditions across multiple continents. In Europe, drought conditions intensified throughout the Iberian Peninsula, France, Italy, parts of the western Balkans, and Greece following an exceptionally dry summer. Exceptionally low river flows persisted through September, rendering navigation nearly impossible on sections of the Rhine river in Germany.
Agriculture and livestock management face immediate pressures in distant regions as well. In New Caledonia, local cattle breeders confronted a two-week dry spell without rain, forcing operations to manage shrinking water reserves and supply supplemental forage to sustain herds during high daytime temperatures.
| Region / Metric | Current Observation | Historical Comparison |
|---|---|---|
| Global Non-Polar Sea Temp (Sept) | 21.05°C | Previous record: 20.92°C (Sept 2023) |
| Niño 3.4 Region Surface Temp | 29.70°C | Exceeds peaks from 1982/83, 1997/98, 2015/16 |
| JMA Pacific Temperature Anomaly | +4.0°C above normal | Previous record: +3.6°C (Dec 1997) |
| Global Surface Temperature (Sept) | 1.63°C above pre-industrial | Second-warmest September on record |
International Warnings and Anticipated Impacts
The World Meteorological Organization (OMM) warned that the ongoing El Niño episode could spark unprecedented temperature peaks, significantly increasing the likelihood of extreme droughts, heavy floods, and widespread heatwaves. Thirteen international meteorological centers project a near 100 percent probability that the phenomenon will persist through February 2027.
Celeste Saulo, Secretary-General of the OMM, explained during a global heat forum in Bangkok that El Niño acts as an accelerator by releasing massive amounts of heat stored in oceans that already reached peak temperatures in August 2026. Projected impacts include excessive rainfall and flood risks across the Horn of Africa, northern Arabia, Central Asia, and parts of the Americas, contrasting sharply with severe rainfall deficits threatening the Indian sub-continent, southern Central America, and the Caribbean.
