Looming El Niño Threat: Could 2027 Become the Hottest Year on Record?
Weather agencies and climate scientists are increasingly observing the potential for an El Niño weather pattern to develop in the Pacific Ocean later this year, a phenomenon that carries the significant risk of driving global temperatures to unprecedented highs in 2027. The possibility, highlighted by both the United States' National Oceanic and Atmospheric Administration (NOAA) and Australia's Bureau of Meteorology, is based on projections from several climate models, although experts emphasize the inherent uncertainties involved in long-range forecasting.
The El Niño-Southern Oscillation (ENSO) cycle, which involves fluctuations in ocean temperatures in the equatorial Pacific, is a major driver of extreme climate events worldwide. An El Niño event is characterized by warmer-than-average sea surface temperatures in the eastern Pacific, extending towards the coast of North and South America. This warming trend typically contributes to a global increase in average temperatures. In Australia, El Niño events are often associated with drier and hotter conditions.
The Bureau of Meteorology recently indicated that some climate models suggest an El Niño development could begin as early as June. However, officials caution that this is a very early projection, with a substantial time lag before the phenomenon is confirmed. NOAA has echoed this sentiment, stating that there is a growing likelihood of an El Niño, while also acknowledging the limitations of current climate models in providing definitive predictions.
According to experts, the current conditions in the Pacific display several precursors indicative of an impending El Niño. A significant amount of warm water has accumulated in the western tropical Pacific. Typically, when the trade winds weaken, this warm water sloshes eastward, warming the waters off the coast of South America. Climate models are currently projecting this eastward sloshing to occur during the Australian autumn, a pattern consistent with historical El Niño events. While these precursors are present, it is still too early to definitively declare an El Niño is forming.
The end of the current La Niña phase, where warmer waters are located closer to Australia, complicates forecasting efforts. Associate Professor of ENSO at the University of New South Wales, notes that predicting beyond the end of La Niña is particularly challenging. She estimates that the probability of an El Niño developing, or the ENSO remaining neutral, between June and August is currently approximately 50/50, essentially a coin toss.
The past three years have consistently ranked among the warmest on record globally. Research from the Berkeley Earth research group suggests that an El Niño event that occurred from mid-2023 to around April 2024 likely added approximately 0.12 degrees Celsius to global temperatures in 2024. If a significant El Niño develops later this year, it is anticipated to peak around November to January, primarily impacting global surface temperatures in 2027 rather than 2026. This leads scientists to believe that 2027 has a high probability of becoming a new record-breaking year for global temperatures, particularly if a moderate to strong El Niño event materializes.
The potential impact of an El Niño on global temperatures is further compounded by the ongoing effects of human-caused climate change, primarily driven by the burning of fossil fuels. Scientists argue that the warming trend caused by greenhouse gas emissions is now so pronounced that it is overshadowing the typical year-to-year variability in air temperatures. This means that even without a strong El Niño, global temperatures are likely to remain elevated. Therefore, the likelihood of 2027 being the hottest year on record is increasingly high, regardless of the specific behavior of the ENSO cycle.
Source:
