The Met Office has projected that 2025 will likely rank as one of the three warmest years ever recorded, continuing the trend of rising global temperatures.
Record-breaking heat in 2024
The year 2024 is on track to become the hottest year in history, with global temperatures expected to surpass 1.5°C above pre-industrial levels for the first time. This milestone follows 2023, which was previously the hottest year on record, with an average global temperature increase of 1.45°C above pre-industrial levels.
Factors behind the warming
The primary driver of these unprecedented temperatures is the increasing concentration of greenhouse gases in the atmosphere. Additionally, natural climate variations, such as El Niño, have contributed to the warming observed in 2023 and 2024. During an El Niño event, heat from the tropical Pacific Ocean transfers to the atmosphere, amplifying global temperatures. Warmer-than-average sea surface temperatures across much of the world's oceans have also played a significant role.
The outlook for 2025
Professor Adam Scaife, head of the Met Office’s global forecasting team, noted that the predicted warmth in 2025 is particularly striking, as it coincides with the tropical Pacific transitioning toward a La Niña phase, which typically brings cooler conditions.
“Interestingly, despite the cooling influence of La Niña, 2025 is forecast to be among the warmest years on record,” Prof Scaife explained. “For context, 2016—a strong El Niño year—was the warmest year globally at the time. But when compared to our projections for 2025, 2016 now appears significantly cooler.”
Temporary boost from El Niño
Prof Scaife added that the 2023/24 El Niño event has temporarily elevated global temperatures, creating a peak in the long-term warming trend driven by greenhouse gas emissions. He also highlighted ongoing research into additional factors contributing to the recent surge in global temperatures.
Sobering milestones
Dr. Nick Dunstone, who led the production of the Met Office’s 2025 forecast, reflected on the significance of these developments. “A year ago, our forecast for 2024 identified the first potential breach of 1.5°C. While this has occurred, it’s essential to recognize that a temporary exceedance of this threshold doesn’t constitute a violation of the Paris Agreement. Nevertheless, surpassing 1.5°C for the first time marks a sobering milestone in climate history.”
Long-term climate trends
The Met Office uses a 20-year average to evaluate the Current Global Warming Level, which is regularly updated on its Climate Dashboard. This metric combines recent observations of global surface temperatures with future climate projections, currently estimating a long-term warming level of 1.3°C above the pre-industrial period (1850-1900). Photo by Richard Knights, Wikimedia commons.