El Niño 2026 intensifies as Pacific sea temperatures rise

El Niño climate change sea surface temperature oceanic warming marine productivity

The 2026-2027 El Niño phenomenon is intensifying, with NOAA reporting that the Niño 3.4 region has reached a +1.8°C sea surface temperature anomaly. This brings the event close to the “very strong” threshold of +2°C. In the Niño 1+2 region off the coast of Peru, anomalies have already reached an exceptional 3.3°C. NASA's PACE satellite has observed a significant drop in chlorophyll-a concentrations in the central equatorial Pacific, signaling a decline in phytoplankton productivity that threatens the marine food web, including fish, birds, and sea lions.

Scientists from CIIFEN and the WMO warn that the global impact of this El Niño has become increasingly unpredictable due to the interaction between natural cycles and anthropogenic global warming. Experts suggest the phenomenon could persist until at least the autumn of 2027. In South America, officials in Venezuela and Chile are monitoring risks to hydroelectric power, water supplies, and increased wildfire potential.

Separately, research from Sun Yat-sen University indicates that continued high greenhouse gas emissions could add more than four hours of extreme heat to hot days by the end of the 21st century. Their analysis of data from 1981 to 2023 shows that extreme heat hours have increased by an average of 62 hours per decade globally.

Entities

Argentina · Buenos Aires · CIIFEN · Chile · International Center for El Niño Research · Lincoln · Mendoza · NASA · NOAA · National Meteorological Service · National Oceanic and Atmospheric Administration · Neuquén

Claims

What the coverage asserts, and how well corroborated each claim is across sources.

[DISPUTED] The El Niño event has a 97% probability of persisting until the beginning of spring 2027. elmauleinforma.cl
[● 5 SOURCES] If greenhouse gas emissions remain high, hot days could accumulate more than four additional hours of extreme heat by the end of the 21st century. www.diariodemallorca.es · www.eldia.es · elheraldodesaltillo.mx · www.levante-emv.com · www.perfil.com
[○ 1 SOURCE] NASA's PACE satellite confirmed lower chlorophyll-a concentrations in the central equatorial Pacific in June 2026 compared to June 2025. bloglemu.blogspot.com
[DISPUTED] NOAA formally declared the start of El Niño after recording equatorial Pacific surface temperatures at least 0.5 °C above average. bloglemu.blogspot.com
[● 2 SOURCES] El Niño could extend until at least the autumn of 2027. www.concierto.cl · elmauleinforma.cl
[● 5 SOURCES] Between 1981 and 2023, extreme heat hours increased by an average of 62 hours per decade. www.diariodemallorca.es · www.eldia.es · elheraldodesaltillo.mx · www.levante-emv.com · www.perfil.com
[○ 1 SOURCE] There is a 63% probability that El Niño will reach very strong intensity between November 2026 and January 2027. nuevaprensa.web.ve
[○ 1 SOURCE] The El Niño phenomenon poses health risks including cardiovascular, respiratory, renal, and dermatological complications. www.diarioextra.com
[○ 1 SOURCE] The Niño 1+2 region off the coast of Peru has reached a relative anomaly of 3.3°C. www.tiempo.com
[○ 1 SOURCE] Scientists from CIIFEN and the WMO warn that the global impact of El Niño has become unpredictable. www.promar.tv
[● 2 SOURCES] NOAA has increased the upper limit of the scale used in its temperature anomaly map to 8°C. www.tiempo.com · www.yourweather.co.uk
[● 2 SOURCES] The Niño 3.4 region recorded a relative sea surface temperature anomaly of +1.8°C last week. www.tiempo.com · www.yourweather.co.uk