2024 First Year to Exceed 1.5C Global Warming Threshold

While the 1.5°C target refers to a long-term average over several decades and has not yet been definitively breached, this development signals the growing urgency of addressing global warming. Fossil fuel emissions continue to drive atmospheric heating, pushing the planet closer to this critical limit.

UN Secretary-General António Guterres recently warned of "climate breakdown," urging countries to take immediate action to slash emissions in 2025. “We must exit this road to ruin – and we have no time to lose,” he said.

Copernicus data shows that global average temperatures in 2024 were about 1.6°C higher than pre-industrial levels. The past decade has now been the warmest on record, with 2024’s heat primarily attributed to human-caused greenhouse gas emissions, though natural events like the El Niño phenomenon also played a role.

“The largest impact on our climate is still the concentration of greenhouse gases in the atmosphere,” said Samantha Burgess, deputy director at Copernicus.

The 1.5°C threshold has become a focal point in international climate discussions, especially for vulnerable nations that see it as a matter of survival. A 2018 UN report warned that the risks associated with climate change—such as heatwaves, rising sea levels, and biodiversity loss—would intensify significantly at 2°C of warming compared to 1.5°C.

Experts predict that the world could cross the 1.5°C long-term average by the early 2030s. While this would have significant political implications, it wouldn’t mark the end of climate action. "Every tenth of a degree matters," says climate scientist Zeke Hausfather, pointing out that even small increases can lead to more extreme weather events, such as heatwaves and heavy rainfall.

2024's extreme temperatures have already contributed to severe weather events, including heatwaves in West Africa, droughts in South America, and devastating storms across North America and South Asia. The recent destructive wildfires in California are another example of how a warming climate is intensifying such events.

In addition to record-breaking air temperatures, sea surface temperatures and atmospheric moisture levels also reached new highs this year. Though the El Niño weather pattern partly explains this year’s extreme heat, scientists have expressed concern over a possible acceleration in the rate of warming beyond expectations.

“This unexpected warmth since 2023, which exceeds predictions, suggests a potential acceleration in warming,” says Dr. Helge Gößling, a climate physicist. However, experts agree that sharp reductions in greenhouse gas emissions could still mitigate the worst effects of climate change.

“Even if 1.5°C is out of reach, we can still likely limit warming to 1.6°C or 1.7°C this century,” says Hausfather. "That’s far better than letting emissions continue unchecked, which could push global temperatures to 3°C or 4°C—far more dangerous for the planet."