La Niña has officially arrived, but its effects are expected to be gentler than usual, according to meteorologists monitoring the situation. This weather phenomenon, characterized by cooler than average sea surface temperatures in the central equatorial Pacific, was confirmed by the National Oceanic and Atmospheric Administration (NOAA) early this January. Lars Lowinski, meteorologist at Weather & Radar, noted, "Forecasts for the winter 2024/25 suggested a more pronounced phenomenon starting from summer... Nevertheless, it took many more months, and until December 2024 there was no clear signal, and it is quite weak compared to what we saw between late 2020 and 2023."
The delayed emergence of La Niña is prompting investigations from experts, with many wondering if the later-than-expected arrival may have been influenced by ocean warming patterns. This story surrounding La Niña is significant not only due to its unpredictability but also for the broader climate disruptions it can prompt globally.
La Niña, part of the El Niño-Southern Oscillation (ENSO) system, alternates with its warmer counterpart, El Niño. While El Niño increases global temperatures and can lead to severe weather events, La Niña often results in cooler global temperatures and distinct weather patterns, including drier conditions across parts of the southern and western United States.
This year, experts predict pronounced drought conditions for northern Mexico and central United States, including Sonora, as La Niña's effects take hold. On January 26, 2025, Dr. Édgar Omar Rueda, from the Department of Agriculture at the University of Sonora, stated, “According to the Climate Prediction Center, this year we expect a more desolate scenario for the livestock sector and wildlife due to the drought caused by La Niña and the unavailability of water.” Rueda emphasized the potential catastrophic effects, particularly for grazing lands, livestock, and even vegetation production for local consumption.
El Niño ended abruptly in June of the previous year after unusual conditions persisted for three years. The cyclical nature of these phenomena can disrupt agricultural practices and threaten food security, particularly during drier months. Rueda elaborated on the expected challenges, saying, “The abnormal drought we are expecting will directly affect pastures and grazing lands, impacting livestock and wildlife.”
The Agricultural Sector Director has already indicated measures to manage water resources amid these projected conditions. With La Niña's presence, prolonged drought could extend beyond spring, affecting temperatures and agricultural outputs significantly. Rueda expressed uncertainty about whether any climatic modifications could occur to produce rainfall before summer.
Lowinski spoke to the impact of La Niña on Europe, noting, “The strongest signal from La Niña is observed during winter due to what we refer to as teleconnection mechanisms, where large-scale weather patterns on one side of the world interact with those closer by.” He explained the significance of monitoring both the Central and Eastern Pacific regions, as conditions there can lead to markedly different weather outcomes across Europe. “If the strongest cold anomaly occurs over the Eastern Pacific, the North Atlantic and Western Europe tend to experience weaker storms or low-pressure systems, leading to drier and sometimes colder conditions,” he added.
Conversely, anomalies evident over the Central Pacific can lead to stronger jet streams and increased storm activity in the Atlantic, resulting in milder, wetter, and windier conditions for Western Europe. Though described theoretically, Lowinski cautioned against oversimplifying, stating, “Other significant factors can affect our weather, including the North Atlantic Oscillation (NAO), stratospheric winds near the equator, and even tropical convection over the Indian Ocean.”
Such climatic dynamics will be closely monitored as predictions suggest a return to neutral conditions before summer 2025, which may prevent any extreme deviations from expected weather patterns.
With La Niña’s impact anticipated to across various sectors, farmers and agricultural developers are bracing for its uncertain effects—following the shift from El Niño conditions. The global interplay of climate phenomena will continue to shape not only weather patterns but also agricultural viability, food security, and more, as researchers and experts strive to stay one step ahead of nature’s whims.