Scientists have discovered a new way to predict El Niño events earlier than before. El Niño is a weather pattern that happens every few years in the Pacific Ocean. It makes some parts of the ocean warmer than usual (El Niño) or cooler (La Niña). These changes can affect weather all around the world.
Previously, scientists from NOAA could predict El Niño about six to 12 months ahead using different models. However, now, a recent study shows they can sometimes predict such events more than two years ahead. This study, published in the journal Geophysical Research Letters on June 16th, looked at thousands of years of climate data to formulate this new method.
Effect of El Niño and La Niña on Contiguous US
Both El Niño and La Niña affect hurricanes in the Atlantic and Pacific oceans. When La Niña happens, it reduces hurricane activity in the eastern Pacific but increases it in the Atlantic. El Niño works the opposite way.
During strong El Niño events, the US Southwest usually gets more rain. On the other hand, during La Niña, this region often experiences hot and dry weather, as reported by Live Science.
Nathan Lenssen, a climatologist from the Colorado School of Mines and the National Center for Atmospheric Research, explained to Live Science that predicting weather beyond a few weeks is hard. However, when factors like ocean, land surface, or ice are involved, predictions can be more reliable because these changes happen slowly over time.
Emily Becker, a climate scientist from the University of Miami not involved in the study, explained to Live Science the importance of predicting El Niño–Southern Oscillation (ENSO) events early. Having more time to predict these events is crucial for planning emergency responses and managing resources effectively.
For example, if there’s a forecast of drought in the coming years, state governments can prepare by implementing water-saving measures or planning for extra water storage ahead of time.
There have been few studies attempting to predict El Niño or La Niña more than a year ahead, as reported by Live Science.
Testing the trustworthiness of El Niño predictions
To verify the reliability of these predictions, Lenssen and his team examined 10 advanced models. These models utilized extensive historical data on sea level, air temperature, rainfall, and other factors to simulate climate conditions.
Essentially, the models recreated a specific period, such as January 2000, and attempted to forecast climate patterns for the following three years—2000, 2001, and 2002—without any additional input. They also indicated whether El Niño, La Niña, or a neutral climate state was probable during those 36 months.
The research team analyzed how well these models forecasted ENSO using data from 1901 to 2009. They found that predicting ENSO was most reliable after strong El Niño events, such as those in 1997 and 2016. Their study demonstrated that these forecasts could be made with confidence up to two years in advance.
