The first to sound the alarm were the weather agencies of Pacific Rim countries, such as Japan and Australia. Later, the World Meteorological Organization (WMO), an official agency of the United Nations, confirmed it: “La Niña” was underway and would occur this year. In other words: the ocean currents at the height of the equator in the Pacific, they had passed the natural phase of heating – a phenomenon that Peruvian fishermen called “El Niño” when it coincided with Christmas – and, after a neutral spring, they headed towards the cold phase in summer.
In scientific terms, this succession of cycles – unpredictable in the long term in terms of intensity and duration – between warm (Niño), neutral and cold (Niña) phases is known as ENSO, acronym for ‘Niño-Southern Oscillation‘. The consequences of this natural alteration of the climate are particularly visible on the continents exposed to the waters of the Pacific: the warmer ocean fuels more intense and torrential storms across the Americas, Asia and Oceania. And this has exacerbated global conditions, so that last year was the hottest on record.
As for the effects on SpainThe relationship is much more indirect and is debated among climatologists themselves. But there are some trends, as the State Meteorological Agency (Aemet) pointed out last year, before the onset of “El Niño”. On the one hand, the warming of the equatorial Pacific was linked to a rainier autumn-winterbut global temperatures would also translate into warmer months. And that’s what happened: the hydrological year brought abundant rains that avoided drought, but the first three months – coinciding with the peak phase of El Niño – were record-breaking in the country.
And then? The “neutral phase” of ENSO, during which the Pacific returned to its usual temperature, has been very good for Spain: after months of record heat, thermometers have normalized and have even remained below normal. The summer has caused a rebound: Aemet recently warned that this August could be one of the three hottest in history. And in between, the mystery of the girl: initially expected in June-August, it seemed to take a long time to form. “El Niño” and “La Niña”, although far awaywere able to influence the atmospheric dynamics that we had to live through,” confirmed the meteorologist Mario Picazo to the SPANISH.
Colder waters form in the tropical Pacific.
Although the transition to La Niña has been slower than initially expected, it is still likely to form later this year. Our bloggers discuss WHEN the transition is likely to occur. pic.twitter.com/8H0Wym7nQu– NOAA Climate.gov (@NOAAClimate) August 8, 2024
Now both The United States National Oceanic and Atmospheric Administration (NOAA) and the Australian Bureau of Meteorology (BOM) confirm that there are 66% chance about what La Niña develops between September and November 2024, increasing 74% possibilities that the phenomenon persists during the northern hemisphere winter. “It seems that La Niña will not be as intense as expected,” he explains. Samuel Bienerweathered climatologist, “but it would arrive throughout the fall.” Regarding the consequences, he warns of great uncertainty. “It is generally linked to stormy autumns in the MediterraneanBut let’s take it with a grain of salt: it hasn’t happened every year.
An “unstable” autumn
The reality is that the month of September – the beginning of the quarter that forms the meteorological autumn – will begin with rains and storms, immersed in the storm that began this week with the passage of a trough of cold maritime air and the formation of several isolated depressions at high levels (DANA). “Based on the forecasts of the European Center, we can say that we are going to have a fairly dynamic atmospheric situation in the first half of September,” confirms Biener. This would imply the “lowering of bags in height”, which could lead to new DANAs of intensity.
Should we fear a new destructive DANA like the one that hit the center of the peninsula in early September 2023? Biener asks “not to panic.” This is a “fairly common” situation at this time of year, even if factors such as high temperatures in the Mediterranean and the Atlantic They serve as “essence” for the evacuation of more torrential and prolonged rains in time. “We have to monitor what could happen in the coming weeks, the conditions are right for the formation of very intense storms. This fall, at least at the beginning, It’s going to be more unstable than last year“.
