The drought that affected Argentina in 2023 could hit the region again in 2024 and 2025 if the climate projections of the World Meteorological Organization (WMO) are met, an organization that this Monday anticipated that the phenomenon known as “El Niño” would end in the middle of this year and would not occur again for the next few months. In that framework, The chances grow that “La Niña” will be repeated towards the end of 2024an effect that impacted South America from 2020 to 2023.
“The 2023/24 El Niño, which helped fuel rising global temperatures and extreme weather around the world, shows signs of coming to an end. A return to La conditions is likely. Niña later this year,” indicates the WMO in its latest report on these two global weather phenomena, which have almost opposite impacts.
WMO forecasts stipulate that between June and August 2024 there is a 50% chance that the El Niño phase will move to “neutral conditions” and a 50% chance that it will mutate into La Niña.
While, There is a 60% chance that La Niña will appear in the July-September period and a 70% chance in August-Novemberaccording to the WMO, which considers that “the risk of El Niño reappearing is negligible during that period.”
According to the agency, the chances of El Niño developing again in the remainder of the year are “insignificant.” The date of the possible return of the dry phenomenon is key because it could coincide with the beginning of the sowing of wheat, corn and soybeans for the 2025 campaign. That is, a new dry season would imply a possible reduction in the harvest and the consequent liquidation of foreign currency from the next year’s agriculture.
La Niña designates the large-scale cooling of ocean surface temperatures in the central and eastern equatorial Pacific, a phenomenon associated with changes in tropical atmospheric circulation.
The Precise effects vary depending on intensity and duration, as well as the time of year the phenomenon occurs and the interaction with other climate phenomena.says the UN organization. The regional factor must also be considered when talking about these effects, since in the tropics La Niña produces climatic impacts opposite to those of El Niño.
The date of the possible return of the dry phenomenon is crucial, since it could coincide with the beginning of the sowing of wheat, corn and soybeans for the 2025 campaign. That is, a new drought could result in a decrease in the harvest and the consequent reduction in the liquidation of foreign exchange from the agricultural sector next year.
How La Niña impacts the climate
El Niño, also known as the Southern Oscillation (ENSO), and La Niña, are two sides of the same natural phenomenon: the change in temperatures of the equatorial Pacific Ocean, especially in its central and eastern regions. This phenomenon affects the climatic conditions of various parts of the world, and in particular those of South America and Argentina. It includes three phases: El Niño, La Niña and a neutral phase.
The effects of this oscillation in Argentina vary depending on the region, the time of year and the eventual phase. For example, during El Niño, spring and summer are usually rainier in our country and can lead to flooding. On the same dates, La Niña usually has below-normal rainfall and can even cause droughts like the one recorded between 2022 and 2023.
The phenomenon has an irregular periodicity and usually occurs every two to seven years. According to the National Weather Service, an El Niño or La Niña phase is declared when sea temperatures in the eastern tropical Pacific increase or decrease 0.5°C above or below average for several consecutive months (5 quarters).
The WMO warned that these natural climate phenomena “are now occurring in the context of a human induced climate changewhich increases global temperatures, exacerbates extreme weather and climate conditions, and impacts seasonal precipitation and temperature regimes.”
In this sense, they noted that the last nine years were the warmest ever recorded even considering the cooling effects of La Niña that lasted from 2020 to early 2023. As for El Niño, it reached its peak in December 2023 and was consolidated itself as one of the five strongest on record.
