La Niña, possible cause of the drought in Spain and in other areas of the planet

La Niña, the natural phenomenon that causes an anomalous cooling of the eastern Pacific near the South American coast, could be behind the serious drought that affects countries such as Spain and Morocco and western states of the United States and, for now, it could be prolonged until well into spring.

Droughts that occur simultaneously in the same hemisphere can be related to each other due to the effect of La Niña, and when this happens, it is documented that there are usually a series of global impacts that affect atmospheric circulation, favoring seasonal patterns. climate in different places on Earth.

In the specific case of the Iberian Peninsula, and after several months with hardly any rain, one can begin to think that La Niña is causing this dry and persistent pattern, explains Juan Jesús González, a physicist, researcher in atmospheric dynamics and spokesperson for the State Meteorological Agency (Aemet).

This natural phenomenon causes notable changes in global temperatures and, especially, in global rainfall regimes and is part of the El Niño Southern Oscillation (ENSO) cycle, which is characterized by warm and cold phases of weather conditions. oceanic and atmospheric pressures in the tropical Pacific Ocean.

For González, this situation of scarcity of rains cannot yet be attributed to climate change: “drought is an intrinsic characteristic of the peninsular climate and this period of absence of rain, which has already lasted for a month and a half, is more or less normal; what is abnormal is what the predictions point out that until March, at the moment, there is no clear scenario of rains”.

The current period of drought in Spain is the consequence of an anticyclonic blockade that causes a prolonged absence of precipitation, in addition to a strong thermal oscillation, with a difference of more than 25° centigrade between the maximum and minimum temperatures in some points.

If the rain were to arrive late, we could start talking about something “anomalous”, details the expert in atmospheric dynamics for whom, if three consecutive months of no rain were finally counted, what would have to begin to wonder is if climate change is behind that situation.

This drought situation is also affecting other areas of the globe, even in a “more noticeable” way, especially in those that are closer to the Pacific Ocean, such as the western United States and Latin American countries, but also in Morocco. .

The Aluite kingdom, being so close to Spain, is strongly influenced by peninsular weather patterns, and today, it is facing its worst drought in the last three decades with a rainfall deficit of 53% compared to the previous season.

On the other side of the Earth, the American West is also suffering the most severe drought in 1,200 years, intensified by climate change, according to research carried out by the University of California (UCLA), which points out that “it is a period of extreme drought, prolonged for more than two decades”.

According to the latest data from the NOAA Climate Prediction Center, the United States weather agency, it is expected that for the winter season, which runs from December 2021 to February 2022, there is an 87% chance that La Niña occurs, and extends through early spring 2022.

Even, and according to the same American meteorological sources, there is a 77% probability that La Niña conditions in the Northern Hemisphere may persist during the months of March-May 2022.