The El Niño weather phenomenon feared in many regions is back. The World Weather Organization (WMO) announced in Geneva on Tuesday that El Niño conditions had returned to the tropical Pacific for the first time in several years. This could further increase global temperatures and alter regional weather and climate patterns.

The WMO assumes with a 90 percent probability that the weather phenomenon will determine the second half of the year. How strong it will be this time cannot yet be said. The last strong El Niño was in 2015/2016. Scientists are divided as to whether El Niño conditions also prevailed in 2018/2019.

“The start of an El Niño significantly increases the likelihood of temperature records being broken, of extreme heat developing in many parts of the world and in the ocean,” said WMO President Petteri Taalas. He called on governments to take precautions to save lives in extreme weather events.

El Niño can exacerbate the effects of climate change

In the central-eastern equatorial Pacific, the monthly mean temperature rose from 0.44 degrees below the long-term mean in February to 0.9 degrees above the mean in mid-June, the WMO reported. According to its own definition, the US climate agency NOAA had already declared an El Niño in June. The WMO includes the expertise of several climate authorities in its calculations.

El Niño has nothing to do with man-made climate change. It is a naturally occurring biennial weather phenomenon associated with warming ocean waters in the tropical Pacific and weak trade winds. However, the phenomenon can exacerbate the consequences of climate change because it has an additional warming effect. The main impacts are in Southeast Asia, Australia, Africa and Central America. For Europe, the consequences are considered limited. The counterpart is La Niña; the past three years have been shaped by this.