Henry Fountain, THE NEW YORK TIMES
Less than a year after one of the strongest El Niños on record, forecasters see an increasing possibility that another will begin later this year.
There is no word yet on how strong a new El Niño might be, but even a mild one could affect weather patterns around the world. Among the potential effects are wetter conditions across the southern United States, including Southern California; a drier Midwest; and drought in parts of Africa, Asia and South America.
An El Niño can also influence global temperatures that are already rising because of greenhouse gas emissions. The strong El Niño of 2015-16 contributed to those years’ being the two warmest on record.
An El Niño occurs when warm water in the equatorial Pacific shifts, creating an immense warm zone in the central and eastern Pacific. This adds heat and moisture to the air, releasing energy that affects the high-altitude winds known as jet streams that circle the planet.