Increasing greenhouse gas buildup and exceptionally high ocean temperatures drove the significantly hot conditions, the new report said.
PRAGUE, Czechia — Last year ranked as the third-warmest year on record, according to a new European Union Space Programme report.
2025 was marginally cooler than 2023, while 2024 remains the warmest year on record and was the first year to be 1.5 degrees Celsius hotter (approximately 2.7 degrees Fahrenheit) than pre-industrial years, according to the Global Climate Highlights 2025 report from the program’s Earth observation component Copernicus.
“Based on the current rate of warming, the Paris Agreement’s limit of 1.5°C for long-term global warming could be reached by the end of this decade – over a decade earlier than predicted based on the rate of warming at the time the agreement was signed,” the report said. “Based on the current rate of warming, the Paris Agreement’s limit of 1.5°C for long-term global warming could be reached by the end of this decade – over a decade earlier than predicted based on the rate of warming at the time the agreement was signed.”
All regions throughout the world showed a clear long-term warming trend, the report said. Temperatures were notably high in both the Antarctic and Arctic regions. January 2025 was the warmest January on record, while March, April and May were each the second warmest for the time of year.
Half the globe experienced more days with at least strong heat stress than average, the report said.
“In 2025, annual surface air temperatures were above the 1991–2020 average across 91% of the globe, the same fraction as in 2024,” officials said in the report. “Nearly half of the globe (48%) experienced much warmer than average annual temperatures.”