The year 2024 has witnessed unprecedented global temperatures, poised to become the hottest year on record and the first to surpass the 1.5°C threshold set by the Paris Agreement above pre-industrial levels. This alarming surge in temperatures is partially attributed to El Niño, a climate pattern characterized by weakened trade winds in the Pacific Ocean, leading to warmer waters in the eastern Pacific. While the emergence of La Niña, the opposite climate pattern, is anticipated in 2025, its cooling effect is projected to be minimal, and 2025 is still expected to rank among the top three hottest years ever recorded. This underscores the relentless trajectory of global warming, driven primarily by the accumulation of greenhouse gases in the atmosphere.
El Niño and La Niña, often referred to as “the boy” and “the girl” in Spanish, are naturally occurring climate patterns with significant global impacts on weather systems. Under normal conditions, trade winds blow from east to west across the Pacific, pushing warm surface waters towards the western Pacific. During El Niño events, these winds weaken or reverse, allowing warm waters to spread eastward, raising sea surface temperatures, particularly off the coast of the Americas. Conversely, La Niña events intensify the east-to-west trade winds, pushing warm waters further west and causing colder water to rise from the ocean depths in the eastern Pacific, resulting in lower sea surface temperatures. These phenomena occur irregularly every two to seven years, typically lasting nine to twelve months, and their influence extends to precipitation patterns and storm intensities worldwide.
While La Niña is expected to emerge between late 2024 and early 2025, the World Meteorological Organization (WMO) predicts its cooling effect will be limited and temporary. The persistent rise in global temperatures, driven by accumulating greenhouse gases, outweighs the short-term cooling influence of La Niña. Even with the anticipated La Niña conditions, 2025’s projected temperatures remain exceptionally high, underscoring the long-term warming trend. This stark reality emphasizes that while naturally occurring climate patterns like El Niño and La Niña can influence global temperatures, the underlying driver of the current warming crisis is human activity.
The unprecedented warmth projected for 2025, even with the potential influence of La Niña, highlights the accelerating pace of climate change. Compared to 2016, a year marked by a strong El Niño and previously considered the warmest on record, 2025’s forecasts indicate significantly higher temperatures. This observation emphasizes the severity of the current warming trend and the diminishing influence of natural climate variations compared to the persistent warming caused by greenhouse gas emissions. It also emphasizes the urgency of mitigating climate change by reducing emissions and transitioning to a more sustainable future.
Although 2024 is predicted to exceed the 1.5°C target above pre-industrial levels set by the Paris Agreement, it’s important to note that this doesn’t signify a definitive breach of the agreement. The Paris Agreement threshold refers to a sustained temperature increase over a period of 20-30 years, not a single year’s anomaly. However, surpassing this benchmark even temporarily serves as a stark warning of the accelerating pace of climate change and the urgent need for global action to curb emissions. The consistent upward trend in global temperatures underscores the critical need to mitigate the long-term consequences of exceeding this threshold for sustained periods.
The precise relationship between climate change and the El Niño-Southern Oscillation (ENSO), encompassing both El Niño and La Niña, is still under scientific investigation. While the fundamental mechanisms of these climate patterns are understood, the influence of climate change on their frequency, intensity, and duration remains an active area of research. Understanding the interplay between human-induced climate change and natural climate variability is crucial for developing accurate climate models and predicting future climate scenarios, allowing for more effective adaptation and mitigation strategies. Continued research in this area is essential for enhancing our ability to predict and prepare for future climate-related challenges.
