Fact check: Study misrepresented to wrongly claim global warming has slowed

The claim: A study shows global warming has slowed significantly over the last 20 years

Average global temperatures have risen nearly 2 degrees Fahrenheit since the late 1800s, and the rate of warming has increased significantly over the last 40 years.

Still, a blog circulating on social media claims a recently released study shows that warming has slowed in recent decades.

"New Evidence Shows Global Warming has Slowed Dramatically Over Last 20 Years," reads the headline of the May 19 blog post, which was shared more than 450 times in less than a month.

The blog references a study recently published in the journal JGR Atmospheres.

However, the claim misrepresents the study.

The study authors say their paper does not show that warming has significantly slowed over the last 20 years. Further, the paper, which introduces a new data processing technique, only tangentially addresses the issues raised in the post.

USA TODAY reached out to the blog author and a social media user who shared the post for comment.

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Study introduces new data processing technique, supports recent warming

Peter Thorne, a Maynooth University professor who was an author of the study, said the paper does not, in any way, support the claim that global warming slowed after the late 1990s.

The rate at which global temperatures are changing was not even the subject of the paper, Thorne, who was also an author of a 2021-2022 Intergovernmental Panel on Climate Change report, told USA TODAY in an email. The paper primarily introduces a new method for processing historical weather balloon data, he said.

The data presented in the paper is consistent with the global warming trend reported by NASA, NOAA and other climate agencies, he said.

Data from these agencies actually shows a marked increase in the rate of warming over the last 20 years, according to Zeke Hausfather, a researcher at Berkeley Earth, a climate data organization.

"The rate of warming over the past 21 years – 2001-2021 – is much faster than the 1980-2000 period," he told USA TODAY in an email.

For instance, Berkeley Earth's data shows that the globe warmed roughly 40% faster between 2001 and 2021 than it did between 1980 and 2000, he said. Similarly, NOAA data shows that Earth warmed 56% faster in the last 20 years than in the prior two decades.

Fabio Madonna, the primary author of the study and a researcher with the Italian National Research Council, agreed with Thorne that the social media claims misrepresented the paper.

"I hope people on social media ... will be encouraged to be more careful when reading a paper," he told USA TODAY in an email.

Fact check: Contemporary, human-driven warming has different ramifications than past warming

Our rating: False

Based on our research, we rate FALSE the claim that a study shows global warming has slowed significantly over the last 20 years. The study in question presents a new data processing technique and does not support the argument that warming has slowed over the last 20 years. Further, climate researchers say the rate of global warming has actually increased since the late 1990s.

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This article originally appeared on USA TODAY: Fact check: Study consistent with increased rate of global warming