Darío Redolat
Climate change and meteorology consultant
El Niño is a phenomenon of natural variation of the Pacific Ocean thermocline layer that has important global implications. During its active phase it can increase the global average temperature by 0.4°C, with large areas of the central and eastern Pacific Ocean having anomalies of more than 2 and 3°C. El Niño is not responsible for global warming, but "gives back" some of the energy absorbed by the ocean during the neutral or La Niña phase, when negative anomalies occur.
Its implications translate into a decrease in the Asian monsoon, the rainy season in the Caribbean or changes in the patterns of marine ecosystems on the coasts of South America, among others.
In the specific case of Spain, no significant correlations have been observed between atmospheric temperature and sea surface temperature in the Pacific that last notably over time. It is true that weak correlations have been found between a positive El Niño phase and a warmer than normal late autumn (specifically for El Niño 1+2, the one closest to South America), but these are not lasting patterns. As for precipitation anomalies, the relationships are even more chaotic and vary greatly depending on location, so it is not appropriate to speak of a specific El Niño effect in Western Europe in general terms. In this case, the direct correlations are linked to oceanic and atmospheric patterns over Europe and the North Atlantic.
As has been observed after other El Niño events (1976, 1998, 2015) in a context of climate change, such excess heat is hardly compensated by La Niña and other subsequent global climate events, so that thermal anomalies persist and are abruptly aggregated with successive such episodes.