The climate crisis is causing extreme El Nino events to become stronger and more frequent, according to a study that may lead to better forecasting models for global weather conditions.
The study, published in the journal PNAS, noted that the El Nino weather phenomenon -- where the surface waters in the central and eastern Pacific Ocean become significantly warmer than usual – causes a shift in the movement of warm water and winds from the western Pacific towards the Americas, changing global weather and heating up an already warm planet.
The researchers, including those from the University of Hawaii in the US, said that continued warming over the western Pacific may trigger more extreme events in the future.
As part of the study, the research team examined details of 33 El Nino events from 1901 to 2017, evaluating the onset location of their warming, their evolution, and their ultimate strength.
The researchers found that with continued global warming, climate factors such as increased sea surface temperatures in the western Pacific warm pool, and easterly winds in the central Pacific may lead to a further increase in the frequency of extreme El Niño events.
The researchers found that all El Nino events beginning in the eastern Pacific occurred prior to the 1970s, while in the western-central Pacific, the weather phenomenon was observed after the decade.
They also identified that four of five known extreme El Nino events in history formed after 1970.
"Simulations with global climate models suggest that if the observed background changes continue under future anthropogenic forcing, more frequent extreme El Nino events will induce profound socio-economic consequences," said study co-author Bin Wang of the University of Hawaii.
According to the study, strong El Nino events in the past have caused severe droughts in the western Pacific Islands and Australia, leading to extensive wildfires and famine, while dangerous flooding from excessive rainfall have plagued northern coasts of South America.
The researchers added that warm ocean temperatures associated with the event has also caused strongly negative effects on fisheries and coral reefs, globally.