Signals of a strong El Niño are emerging in the equatorial Pacific, with forecasts suggesting it could become a Super El Niño, bringing floods, droughts, and fires globally while accelerating warming.
What is El Niño?
El Niño and La Niña are recurring climate patterns in the tropical Pacific Ocean that occur every few years and significantly influence global weather. El Niño is characterized by unusually warm sea surface temperatures along the equatorial Pacific, coupled with changes in wind patterns and precipitation. For an El Niño to be declared, temperatures in a specific Pacific region must exceed the long-term average by at least 0.5°C. A "Super El Niño" occurs when temperatures rise more than 2°C above average, leading to more severe global impacts.
Current Developments and Forecasts
Signs of an impending El Niño have been growing, with expectations of its arrival by late summer or early fall. Recent data shows large volumes of warm water spreading from the western to eastern tropical Pacific, a classic precursor. Notably, the European ensemble model projects sea surface temperatures could surpass the 2°C threshold, qualifying as a Super El Niño. However, forecast accuracy is lower during the spring due to the "spring predictability barrier," introducing uncertainty in intensity predictions.
Projected Global Impacts
El Niño's effects vary by region, often causing contrasting extremes:
- Flooding risks: California and the southern United States, Southeast Asia, and southeastern South America.
- Drought and fire hazards: Australia, northern South America (including parts of the Amazon), Central and Southern Africa, India, and parts of Asia.
- Heat waves: Increased likelihood globally, including in the US and other continents.