Risings temperatures are likely to double the number of weather events fuelled by strong El Ninos in the near future, according to University of New South Wales researchers.
Thanks to global warming, intense El Niños, which currently hit every 20 years will soon start occurring every 10 years, University of New South Wales researchers revealed in a press statement.
An El Niño is the warm phase of a long-standing natural climate cycle in the Pacific Ocean. Changing wind patterns result in the collection of warm water in the eastern part of the equatorial Pacific, this redistribution of hotter water triggers changes in atmospheric circulation that influences rainfall and storm patterns around the world.
"El Nino events are a multi-dimensional problem, and only now are we starting to understand better how they respond to global warming," said co-author, Dr Agus Santoso of CoECSS in the statement. "Extreme El Niño events develop differently from standard El Ninos, which first appear in the western Pacific. Extreme El Nino's occur when sea surface temperatures exceeding 28°C develop in the normally cold and dry eastern equatorial Pacific Ocean. This different location for the origin of the temperature increase causes massive changes in global rainfall patterns."
For this study, researchers used 20 climate models that consistently simulate major rainfall reorganization during extreme El Niño events. They found a substantial increase in events from the present-day through the next 100 years as the eastern Pacific Ocean heats up in response to global warming.
"Under global warming, the barrier to convection shifts," the authors of the study told LiveScience. "Therefore, it is easier to generate this massive atmospheric circulation associated with an extreme El Niño event."
The increase in frequency of El Ninos may come as a blessing in disguise for drought-stricken western United States, which would receive extra rainfall.
The last El Nino that occurred in 1997-98 resulted in the hottest year on record, accompanied by cyclones, floods, wildfires and droughts. It killed approximately 23,000 people and caused damages of up to $35 billion.
