As the natural weather phenomenon known as El Niño makes its presence felt, scientists are warning of its potential to trigger extreme weather conditions worldwide. The National Oceanic and Atmospheric Administration (NOAA) has reported that the current El Niño phase is likely to intensify throughout 2026, with predictions indicating it could be among the strongest events recorded to date. Coupled with longstanding human-induced climate change, 2027 could emerge as the hottest year ever documented, bringing significant disruptions to weather patterns, food security, and economies.
Understanding El Niño
El Niño occurs in the Pacific Ocean and is characterised by changes in wind patterns and sea surface temperatures. Typically, winds blow from east to west across the Pacific, but during an El Niño event, these winds weaken or even reverse. As a result, warmer water spreads across the central and eastern tropical Pacific, leading to profound atmospheric changes.
The NOAA announced the onset of the current El Niño phase after observing that sea surface temperatures in the central tropical Pacific had risen more than 0.5°C above historical averages. This shift is accompanied by reduced atmospheric pressure in the central Pacific compared to the western regions, signalling a definitive start to the phenomenon. The Japanese Meteorological Agency corroborated these findings, adding to the growing consensus among scientists.
Predictions of Unprecedented Strength
Experts are particularly concerned about the current El Niño’s intensity, which may be exacerbated by unusually warm subsurface waters. According to the United Nations’ World Meteorological Organization (WMO), these deeper waters are approximately 6°C warmer than normal in certain areas. When deep ocean heat is present, it often results in elevated surface temperatures.
A “very strong” El Niño—defined as surface temperature increases of 2°C or more sustained over time—has been observed only a handful of times since 1950. The NOAA has indicated a 63% likelihood that this El Niño will reach such a classification, positioning it among the most significant events on record. The phenomenon is expected to persist at least into early 2027.
The Implications of a Strong El Niño
A robust El Niño can drastically alter weather patterns globally, intensifying droughts and heavy rainfall, as well as heightening the risk of heatwaves both on land and in aquatic environments. Celeste Saulo, Secretary-General of the WMO, noted that during El Niño events, the ocean transfers heat to the atmosphere, resulting in higher global temperatures.
The effects vary by region and season. For instance, South America, Southeast Asia, and Australia often experience hot and dry conditions, increasing the likelihood of droughts and wildfires. Conversely, the southern United States may face heavier rainfall, which can lead to flooding. While El Niño typically brings more tropical storms to the eastern and central Pacific, it tends to reduce storm activity in the tropical Atlantic, including the southeastern United States.
In the UK, the potential impacts are more nuanced, with forecasts suggesting a possibility of a mild start to winter followed by a colder end, according to the Met Office.
Societal Impact and Food Security
António Guterres, Secretary-General of the United Nations, has urged global preparedness for the repercussions of El Niño, asserting that its effects will amplify the challenges posed by a warming planet. The anticipated droughts in South America and Southeast Asia could severely impact crop production, coinciding with ongoing disruptions in fertiliser distribution due to geopolitical tensions, particularly around the Strait of Hormuz.
This could lead to reduced harvests, increased food scarcity, and soaring prices. Fishing communities in South America may also suffer as nutrient-rich waters become less available, threatening fish populations such as anchovies that rely on these resources.
Historical comparisons are being drawn to the El Niño of 2015-16, one of the strongest on record, which resulted in significant water shortages in the Caribbean, an unprecedented storm season in the central Pacific, and drought conditions in the Horn of Africa. The combined effects of extreme weather during that period contributed to widespread food shortages, impacting millions globally as documented by the UN’s Food and Agricultural Organization.
Climate Change and El Niño
While El Niño events have displayed increased intensity since 1950, the Intergovernmental Panel on Climate Change (IPCC) has indicated that there is no definitive evidence linking climate change to the frequency or strength of these events. However, some climate models suggest that global warming may make El Niño episodes more frequent and intense in the future, although this remains a complex and uncertain area of study.
Notably, the impacts of El Niño will occur against the backdrop of ongoing climate change, which has already been driving increasingly severe weather extremes across the globe. As societies grapple with these dual challenges, the need for robust climate adaptation strategies becomes ever more critical.
Why it Matters
The resurgence of El Niño is not merely a meteorological curiosity; it serves as a harbinger of significant climatic shifts with far-reaching implications. As this phenomenon unfolds, it is poised to exacerbate existing challenges related to food security, economic stability, and environmental sustainability. In an era marked by climate change, understanding and preparing for the impacts of El Niño is essential for safeguarding vulnerable communities and ecosystems worldwide.
