Earth is now warming twice as fast as in previous decades

Global warming has accelerated and is now twice as fast as in previous decades, meaning major climate disasters could occur sooner than expected.

The Earth warmed by about 0.18°C per decade before 2013-14. Since then, it has warmed by about 0.36°C per decade, according to an analysis by Stefan Rahmstorf at the University of Potsdam in Germany and his colleagues.

If warming continues at this rate, humanity could breach the Paris Agreement’s goal of limiting warming to 1.5°C in 2028, even sooner than other research has predicted.

“Every tenth of a degree matters and worsens the impact of global warming in terms of extreme weather events, in terms of impacts on ecosystems and also the risk of exceeding tipping points,” says Rahmstorf. “The world, except the US, is trying to stop global warming, to reduce it, and so the big concern is the fact that now it’s actually doing the opposite, it’s accelerating.”

After a series of record hot years, climatologists began to widely debate in 2023 whether global warming is accelerating. However, natural fluctuations such as the El Niño climate phase, which caused further warming in 2023 and 2024, made it difficult to determine whether the faster rise in temperatures was due to climate change or just random weather.

Rahmstorf’s study is the first to find a statistically significant acceleration due to climate change, making the attribution 98 percent confident.

The team analyzed five different sets of global temperature data, some of which show a higher number. Global warming could reach 1.5°C above pre-industrial levels this year, based on a 20-year average, according to an analysis of a dataset by the European Center for Medium-Range Weather Predictions.

Warm-water coral reefs are beginning to collapse and, if exceeded, 1.5°C threatens to exceed other tipping points, such as the irreversible melting of Greenland and West Antarctica and the demise of the Amazon rainforest.

Many scientists believe that the acceleration in global warming was mainly due to the 2020 crackdown on sulfur dioxide in shipping emissions. While harmful to human health, this substance also created an aerosol haze that blocked sunlight and cooled the planet.

Now that that sunlight has been unblocked, the rate of warming may have slowed, but it’s hard to say for sure, Rahmstorf says. The transition away from fossil fuels will continue to reduce the air pollution that masks warming.

“There will be further reductions in aerosol, [but] probably not as fast as emissions from shipping have decreased,” he says. “It’s quite possible that the rate of warming will be lower in the next decade.”

In addition to El Niño, the authors estimated the effects of volcanic eruptions, which also produce sun haze, and increased solar radiation during high sunspot cycles. After excluding these influences, they fitted two types of curves to global temperatures, both of which showed an acceleration of warming, albeit at different times.

However, it is unlikely that scientists will be able to completely remove the temperature effects of El Niño, volcanoes and sunspots. Zeke Hausfather on Berkeley Earth in California. This means they could be slightly overestimating how much global warming has accelerated. But the study offers compelling evidence that it has accelerated, he says.

“The broader conclusion is that we have strong evidence for an acceleration, even though we don’t know exactly how much the rate of warming has increased yet,” says Hausfather. “We’ll have to wait a few more years to get more data.”

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