Did we surpass 1.5 C of warming in 2024? It depends on who you ask

Today, six climate agencies from around the world all confirmed what we knew was coming: Earth once again experienced its hottest year on record.

But whether or not it surpassed 1.5 C above the pre-industrial average depends on which climate agency you look at.

According to the EU's Copernicus Climate Change Service, 2024 was the warmest year on record dating back to 1850, coming in at 1.6 C above the pre-industrial average (1850-1900). It beat out 2023 as the hottest year on record, which was 1.48 C warmer than the pre-industrial average. 

However, according to NASA, 2024 was 1.47 C warmer than the pre-industrial average, hovering ever so close to 1.5 C. 

The National Oceanic and Atmospheric Administration (NOAA) found that it was 1.46 C warmer.

Berkeley Earth, a non-profit climate analysis organization, also found that 2024 was 1.62 C warmer than the pre-industrial average.

The numbers vary among the agencies due to the way the climate agencies gather past data.

However, the World Meteorological Organization looked at all these analyses, plus those from the U.K.'s Met Office and Japanese Meteorological Agency, and found that we "likely" passed 1.5 C of warming in 2024.

But what is agreed upon is that the past 10 years have been the warmest on record.

Though this may be the first calendar year to surpass the 1.5 C threshold set out in the Paris Agreement, it doesn't mean that we've broken that agreement. That threshold — the pledge from 195 countries to keep global warming below 1.5 C of the pre-industrial average — applies to many years where Earth's temperature is consistently above that, not just one or two.

And it also doesn't mean there's no hope to keep warming from going beyond that goal. As climate scientists often say, "every fraction of a degree matters."

This isn't the first 12-month period of warming above that threshold. From mid-2023 to mid-2024, the planet was 1.5 C warmer. It's just that it didn't happen over a calendar year.

While there may be some disagreement as to the exact degree of warming — in just the hundredths of a degree — the message is the same: Earth keeps getting warmer.

"What we can say, I think, is that it's likely that 2024 breached the 1.5 limit," said Gavin Schmidt, director of NASA's Goddard Institute for Space Studies. "However, the impacts that we're seeing, if it's like 1.48 or 1.52 or 1.6 you know, they're pretty much the same."