2025 was one of the hottest years on record, data finds

Climate change reaching 'end-game,' requires 'World War II emergency mobilization' to avert societal collapse by 2050, report says

Climate change is reaching the ?end-game? and could pose an existential threat by 2050, according to a new policy paper, which outlined an urgent ?hothouse Earth? scenario that could be prevented with a ?World War II emergency mobilization."

GENEVA, Switzerland - It’s official: 2025 was Earth’s third-warmest year since records began in 1850 — extending an unprecedented global heat streak into its third year.

The World Meteorological Organization (WMO) and the National Oceanic Atmospheric Administration (NOAA) confirmed the data on Wednesday.

2025 was one of the hottest years on record 

By the numbers:

According to the data, global average temperatures in 2025 were 1.3°C (2.4°F) above pre-industrial (1850-1900) levels.

Two of the World Meteorological Organization’s datasets ranked 2025 as the second warmest year in the 176-year record, and the other six ranked it as the third warmest year. The past three years, 2023-2025, were the three warmest years in all eight datasets.

What they're saying:

"The year 2025 started and ended with a cooling La Niña and yet it was still one of the warmest years on record globally because of the accumulation of heat-trapping greenhouse gases in our atmosphere," WMO Secretary-General Celeste Saulo said. "High land and ocean temperatures helped fuel extreme weather – heatwaves, heavy rainfall and intense tropical cyclones, underlining the vital need for early warning systems."

People try to stay cool at the beach at Coney Island in Brooklyn as the region experiences a heatwave on July 30, 2025 in New York City. (Credit: Spencer Platt/Getty Images)

She added: "WMO’s state of the climate monitoring, based on collaborative and scientifically rigorous global data collection, is more important than ever before because we need to ensure that Earth information is authoritative, accessible and actionable for all," said Celeste Saulo.

Ocean temperatures were among the highest in 2025

Dig deeper:

The news comes on the heels of a separate study published in Advances in Atmospheric Sciences last week, which said that ocean temperatures were also among the highest on record in 2025, reflecting the long-term accumulation of heat within the climate system.

About 90% of excess heat from global warming is stored in the ocean, making ocean heat a critical indicator of climate change. 

The study found the global annual mean sea surface temperature (SST) in 2025 was 0.49 °C above the 1981–2010 baseline and about 0.03 °C lower than in 2024, consistent with the development of La Niña conditions, but still ranking as the third-warmest year on record.

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Climate Central said the planet is rapidly approaching the goal to limit long-term warming to 1.5°C, above which the risks to lives, livelihoods, and ecosystems from pollution-fueled warming and extreme weather will intensify further.

The organization said most of the world is progressing rapidly in this direction. Globally, 70% of the increase in electricity demand in 2024 was met with renewable energy like wind and solar. 

But in the U.S., recent progress in the clean energy transition may face challenges. As of January 2026, the U.S. rolled back landmark 2021-2022 policies to boost clean energy and climate resilience, and is withdrawing from the Paris Agreement as well as from the United Nations Framework Convention on Climate Change and the Intergovernmental Panel on Climate Change.