Climate: Phenomenon’s Return Feared to Fuel Global Temperature Peak

A man in the middle of his rice field totally victim of drought caused by the El Nino phenomenon in Bulacan (Philippines) on April 13, 2016.

Climate: Why the Return of the El Nino Phenomenon Is Feared Read More

Petteri Taalas, Secretary-General of the United Nations World Meteorological Organization, warned that it could “fuel a new global temperature peak”.

Meteorologists and climate scientists around the world are on high alert. “An important evolution of the planetary climate system is taking place this summer with the probable emergence of the El Nino phenomenon,” wrote Meteo France on Monday, April 24, in its three-month forecasts. Some scenarios even anticipate a “super El Nino” to come.

What is El Nino?

El Nino is a meteorological phenomenon that results in a rise in the temperature of the surface water in the east of the Pacific. It occurs cyclically but irregularly, every three to seven years, and causes climate disasters, in particular droughts and higher-than-normal precipitation.

The phenomenon typically reaches maximum intensity towards the end of the year, which is why it is called El Nino, which also means the child Jesus in Spanish. Its impact is global, explains Jerome Vialard, oceanographer and research director at the French Research Institute for Development to France 24.

“It’s such a powerful phenomenon that it has an influence on the climate on the entire globe.”

In 2016, France Televisions journalist Nicolas Chateauneuf presented the phenomenon on the “20 Heures” of France 2. He explained that with El Nino, the equatorial heat of the Pacific is not pushed towards Asia and Australia, but rather stays close to Latin America. El Nino is different from La Nina, which tends to lower ocean temperatures. According to the World Meteorological Organization (WMO), this phenomenon is ending, having been ongoing since 2020. There is a normal alternation between La Nina and El Nino, with neutral conditions between the two.

What do we know about its return?

Nothing is certain. We are still at the stage of probabilities. But they point towards a return of El Nino. “Today, we are already observing strong climate signals, indicating a significant warming of the equatorial Pacific Ocean,” climate scientist Thomas Abinun at Meteo France explained to Nouvelle-Caledonie La 1ere.

“This is a signal that we are monitoring because this warming of the ocean could lead to the emergence of an El Nino episode starting in the second semester.”

This observation is shared across the planet. According to the WMO, the chances of El Nino developing are estimated at 15% in April-June, 35% in May-July, and 55% in June-August. The US National Oceanic and Atmospheric Administration (NOAA) writes in its update bulletin published on 24 April (PDF in English) that there is a 62% chance that the phenomenon will reappear by the summer, a figure that approaches 90% by the end of the year.

” You can compare that to a loaded gun,” Axel Timmermann, a climate specialist at Busan University in South Korea, told The Guardian. “The charger is full, but the atmosphere has not yet pulled the trigger.”

But why talk of a potential “super El Nino”?

The Australian Bureau of Meteorology reports that some forecast models suggest a possible appearance of a “super El Nino”

or this year. The classic phenomenon corresponds to an increase in the temperature of the equatorial Pacific of 0.8°C above normal, whereas a “super El Nino” is characterized by an increase of at least 2°C. These higher temperatures would bring more powerful effects.

Such a phenomenon is rare. Specialists only count three in the last forty years: 1982-1983, 1997-1998, and 2015-2016. “The temperatures in 2016 and, to a lesser extent, in 2015, were driven higher by an exceptionally powerful El Nino,” the WMO noted in 2017.

However, we should emphasize the high level of uncertainty, and all scenarios mentioned must be approached with great caution. “We need two or three more months to have a more reliable idea of what is going to follow,” warned Alvaro Silva, an OMM consultant.

What could be the consequences for the global climate?

It is impossible to be precise at this stage. El Nino “risks fueling a new global temperature peak,” warns Petteri Taalas, Secretary-General of the WMO. Previous episodes had raised the mercury all over the world. So, the same consequences should be expected, especially as the eight last years (2015-2022) were the warmest ever recorded on the planet, while La Niña tends to lower ocean temperatures.