La Niña, which emerged in January, is seeing rapid changes signaling its possible end, coinciding with coastal El Niño warming in the eastern Pacific. This shift could contribute to record global temperatures and lessen hurricane activity in the Atlantic. While predictions remain uncertain, the implications for weather patterns in Peru and globally are significant, necessitating ongoing observation.
The phenomenon of La Niña, which emerged in January, is seeing swift changes that could potentially signal its imminent end. La Niña generally cools the Pacific Ocean; however, it has not significantly alleviated global heating trends, particularly evident throughout 2024 and 2025 — with notable exceptions in the U.S. Recent developments indicate the possibility of continued record-high global temperatures as La Niña wanes.
A new weather pattern, known as coastal El Niño or El Niño Costero, has caused ocean temperatures in the eastern Pacific to rise by over five degrees above average. This warming phenomenon can have far-reaching effects, as past coastal El Niño events, such as those in 2017 and 2023, led to severe flooding and an increase in vector-borne diseases like dengue fever in Peru. The duration of this warming event remains uncertain, potentially influencing global temperatures and hurricane activity in the Atlantic region.
Last week, the National Study of the El Niño Phenomenon (ENFEN) issued an “El Niño Costero Watch,” indicating that if elevated sea temperatures persist for three months, an El Niño Costero will be declared. The shift from strong to weak winds between January and February caused a rapid transition from cooler to warmer seas, disrupting the cold upwelling process. This unexpected shift raises concerns, as significant rainfall could inundate usually arid regions in Peru, impacting local ecosystems and human activities.
Peru is at heightened risk from this coastal warming, which impacts approximately 75 percent of its population. Abraham Levy, a meteorological consultant in Peru, highlighted that each coastal El Niño leaves a unique impact, typically characterized by excessive heat and atypical rainfall. If the warming event extends into autumn, it could detrimentally affect local fisheries and agriculture, straining fish populations and leading to food insecurity.
El Niño incidents have previously resulted in severe weather events, including flooding and cyclones, with the 2023 event even catalyzing an outbreak of dengue fever. Current forecasts suggest a full El Niño event is unlikely within 2025, with a maximum probability of one in five, according to the International Research Institute for Climate and Society. Additionally, the World Meteorological Organization currently views the prospect of a full El Niño developing in the first part of the year as negligible.
Despite a coastal El Niño forming, the persistent cooler seawater in the central Pacific maintains the characteristics of La Niña. The potential ephemeral nature of La Niña this year suggests it may not offer sufficient cooling to bring down global temperatures from near-record highs. The World Meteorological Organization estimates a 60 percent probability of conditions shifting to ENSO-neutral between March and May.
Ken Takahashi Guevara pointed out that the cooling effects of La Niña could linger longer than current metrics suggest, due to ongoing human-induced ocean warming. This discrepancy may lead to complex climatic effects, with warm water developing in the eastern Pacific potentially diminishing the likelihood of an active hurricane season in the Atlantic. This evolving situation could signal another year of elevated global temperatures, regardless of the short-lived nature of La Niña.
In summary, the rapid evolution of La Niña and the emergence of a coastal El Niño present significant implications for global temperatures, hurricane activity, and Peruvian weather patterns. The persistent warming in the eastern Pacific may exacerbate the impacts of climate change, suggesting continued elevated global temperatures while potentially undercutting hurricane activity in the Atlantic. As scientists continue to monitor these developments, the interplay between these phenomena warrants close scrutiny.
Original Source: www.washingtonpost.com
