AA correspondent compiled the questions about El Nino and its effects in 10 questions.
1- What is El Nino?
El Nino, a Spanish word meaning "boy" in Turkish, is defined as a weather phenomenon that occurs when sea surface temperatures rise above normal in the central and eastern parts of the equatorial Pacific.
The El Nino event begins when the sea water temperature in the region called Nino 3.4, which covers the central and eastern parts of the equatorial Pacific, reaches a certain degree.
NOAA uses the 3-month average of sea surface temperature in this region as a basis to determine whether El Nino is in effect. El Niño conditions are considered to have occurred if the ocean temperature remains 0.5 degrees above normal for 5 consecutive 3-month periods.
2- When did the current El Nino start and until when will it be effective?
El Niño event occurs every 2 to 7 years and lasts approximately 1 year. NOAA announced that the latest El Niño event officially began in June. Sea water temperature in the Pacific is expected to reach its peak in the November-December-January period and then decline, and El Niño conditions are expected to gradually weaken in the spring months of 2027.
3- What makes the 2026-27 El Nino different from other El Nino events in the past?
El Nino periods when the sea water temperature rises 2 degrees above normal are called "Very strong El Nino" or "Super El Nino". Previously, El Niño events in 1982-1983, 1997-1998 and 2015-2016 were included in this category. According to NOAA's forecasts, there is a more than 90 percent chance that the current El Nino will develop into a very strong El Nino in the fall and winter.
Last July, Pacific waters were found to be 2 degrees warmer than normal. This anomaly is expected to continue to increase and exceed 2.5 degrees in the October-November-December period. This shows that the current El Nino will be the strongest El Nino event on record, with a 69 percent probability, let alone being a Super El Nino.
4- How does El Nino trigger air temperatures and extreme weather events?
Analysis shows that a strong El Nino increases the global average temperature by 0.2 degrees. The Pacific Ocean, which covers almost one-third of the Earth's surface, is also a huge source of energy and moisture for the atmosphere. As the sea surface warms during El Niño, evaporation also increases and more heat and water vapor is carried into the atmosphere. This causes temperatures to increase in some regions and the formation of strong rainfall and storm systems in some regions.
The rainfall pattern in the Western Pacific, one of the regions where heavy rainfall normally occurs, can shift eastward during El Niño. This change can affect atmospheric pressure and wind systems. Jet streams and the response of large-scale air circulation can change weather conditions even in regions thousands of kilometers away.
5- Which regions will be most affected?
El Nino effects are felt most strongly in tropical regions. Although not every El Niño event has the same severity, generally more rainfall, floods, landslides and coastal floods can be seen in Peru and Ecuador, drought in South Africa, Colombia, Indonesia and Australia, a decrease in monsoon rains in India, wetter conditions in the south of the USA and warmer conditions in the north, floods in the south of Brazil and drought in the north.
During El Nino periods, the hurricane season in the Atlantic is calmer.
6- What are the effects other than extreme weather events and temperature increases?
The risk of forest fires also increases in regions where El Nino causes temperatures to increase. Apart from this, the most important impact shows itself in agricultural production. Both drought and excessive rainfall affect agriculture and global food stocks.
7- To what extent does El Nino affect the economy, agriculture and food prices?
Although the effects of the current El Nino have not yet fully manifested themselves, the El Nino events of previous years are thought to have caused trillions of dollars of loss in the global economy.
According to a study published by Dartmouth College researchers in the journal Science in 2023, El Niño, which was effective in 1997-98, caused a loss of approximately 5.7 trillion dollars in global income in the following 5 years.
According to the warning made by the Food and Agriculture Organization of the United Nations (FAO) in June, the probability of drought in some agricultural and pasture areas has exceeded 50 percent in large parts of South and Southeast Asia, Central America, the Caribbean, the Sahel region and Southern Africa, where the risk is highest.
The World Food Program (WFP) has warned that a strengthening El Niño weather event could push at least 49 million more people into acute food insecurity by the end of 2027.
8- Will Türkiye be affected by El Nino?
Türkiye is not among the regions where the most significant effects of El Nino are seen. The effect of El Nino on the weather conditions in Türkiye and the Mediterranean basin may occur not directly, but through atmospheric circulation and in a more uncertain way. The Mediterranean basin generally tends to have a warmer and drier autumn-winter during El Niño years. Experts point out that this situation may cause temperature anomalies to continue in the coming months in Türkiye, located in the Mediterranean basin, and an increase in the risk of forest fires due to an extended fire season.
9- What is the difference between El Nino and La Nina?
La Nina, which is the opposite phase of El Nino and means "daughter" in Turkish, occurs when sea surface temperatures in the equatorial Pacific drop below normal and tends to reduce global average temperatures. La Nina conditions do not always prevail after El Nino. In the transition between these two weather events, neutral conditions, that is, natural weather events, can have an effect.
10- Is there a connection between climate change and El Niño?
There is no definitive consensus in the scientific community on the relationship between climate change and stronger El Niño events. However, recent studies indicate that global warming may lead to stronger El Niño events. Sea surface temperature extremes caused by El Niño have strengthened by about 10 percent compared to pre-1960 levels, according to a study by researchers at Imperial College London in England.
