BENGALURU: As 2024 edges closer to its end it is on track to become the warmest year ever recorded, surpassing 2016. Among the key factors driving this record-breaking warmth is the unexpected absence of La Niña, a climatic phenomenon that global weather models had predicted to emerge earlier this year. Despite repeated forecasts, La Niña has failed to materialize, leaving experts scrambling to understand what went wrong.
La Niña, a cooling phase of the El Niño Southern Oscillation (ENSO), typically brings colder sea surface temperatures in the central and eastern Pacific Ocean, stronger trade winds, and increased rainfall in regions like India. This phase is part of a larger cycle that includes El Niño, a warming phase, and the neutral phase, characterized by average sea surface temperatures. For India, La Niña has historically been associated with cooler winters and heavier rainfall, while El Niño tends to produce drier and warmer conditions.
However, 2024 has defied expectations. According to the United States’ National Oceanic and Atmospheric Administration (NOAA), ENSO-neutral conditions have persisted throughout the year. As of December 9, the Oceanic Niño Index (ONI), which monitors sea surface temperatures in the Pacific’s Niño 3.4 region, stood at -0.3°C. A La Niña event is officially declared when this index dips to -0.5°C or below for three consecutive months.
Earlier predictions had suggested that La Niña would emerge as early as August or September, but the timeline was later revised to October-December. The latest projections now hint at a weak and short-lived La Niña phase between December and February. Experts believe that even if La Niña does appear, it is unlikely to have any significant impact, and ENSO-neutral conditions are expected to resume by March-May 2025.
The failure of La Niña to develop as forecasted has exposed limitations in global weather models. These models tend to perform well when there are strong, pronounced shifts in sea surface temperatures, as is often the case with robust El Niño or La Niña events. This year’s subtle temperature fluctuations appear to have thrown predictions off course. Additionally, other complex climatic factors, such as atmospheric pressure and wind patterns, may have played a role in the models’ inaccuracies.
In India, the absence of a strong La Niña could mean warmer winter conditions, as the cooling influence typically associated with the phenomenon is expected to be minimal. This aligns with the broader trend of rising global temperatures, which continues to push the planet into uncharted territory.
As the world grapples with the realities of climate change, the inability to accurately predict La Niña underscores the growing challenges of understanding and forecasting complex weather systems. Scientists are now focusing on refining predictive models to ensure they can better anticipate and prepare for the changing climate in the years to come.