Skip to main content

Temperature and sea ice data consistent with human-driven climate change | Fact check

Kate S. Petersen   Paste BN
play
Show Caption

The claim: Sea ice and temperature data show climate change is a hoax

A Jan. 29 Facebook post (direct link, archive link) shows heat maps of the U.S. and makes a series of claims about climate and weather.

"Global cooling was real from 1944 to 1982," reads text in the post. "Global warming was real from 1983 to 2006. Since 2007, sea ice has been expanding at both poles. 2021 was the coldest winter ever recorded in Antarctica. The Earth goes through cycles which aren't caused by man."

The post also states that January 1990 was warmer than 2025 and asks "a climate hoaxer" for an explanation.

The post was shared more than 2,000 times in two weeks.

More from the Fact-Check Team: How we pick and research claims | Email newsletter | Facebook page

Our rating: False

Extensive evidence, including global temperature and sea ice data, shows that Earth's climate is changing due to human activity. The post includes inaccurate information about global temperature and sea ice trends.

Inaccurate and misleading data in post

Contrary to the claims in the post, Earth warmed from 1944-1982 and from 1983-2006, according to National Oceanic and Atmospheric Administration data. Warming also continued beyond 2006 to the present.

When NOAA's entire data set is taken into account, the agency reports a global land surface warming trend of 0.18 degrees per decade from 1850-2024.

Sea ice extent, or area, has not expanded at either pole since 2007, Walter Meier, a research scientist at the National Snow and Ice Data Center, told Paste BN.

"The (sea ice extent) trends for the Arctic and Antarctic are negative since 2007," he said in an email.

The downward trend in the Arctic does not meet a statistical significance threshold for many months, mainly due to the relatively short timeframe, Meier said. However, the trend is significant for all months in the Antarctic due to a downward shift that began in 2016.

"One needs to be cautious about making too strong of conclusions from a relatively short time," he added. "There is still variability and it would not be surprising to have periods with a positive trend over a number of years even as the longer-term trend remains negative. Also, for the Arctic, the period since 2007 has been marked by much thinner ice, so it is not only extent that has been low, but the overall volume and mass of the Arctic sea ice."

When the entire satellite record is taken into account, Arctic sea ice extents have declined significantly since the late 1970s, but there is no clear trend for Antarctic sea ice, Paste BN previously reported.

The post also claims that Antarctica experienced its coldest winter on record in 2021, which isn't quite right.

The continent experienced its coldest "polar darkness period" (April-September) that year, Theodore Scambos, an Antarctic researcher at the University of Colorado, told Paste BN in an email. But its coldest winter (June-August) on record was in 2004, followed by 2021.

More: 'Green' energy needs metal. Can we combat climate change while reducing mining impacts?

The post correctly states that January 2025 was colder than January 1990 in the U.S. However, the U.S. warmed overall during that timeframe, according to NOAA data.

This is possible because short-term temperatures are influenced by both natural weather fluctuations and human-caused climate change, as Paste BN previously reported.

In the U.S., January has warmed about 0.12 degrees per decade since 1990, according to NOAA. Annual temperatures have warmed around 0.46 degrees per decade since 1990.

Extensive evidence Earth's climate changing due to human activity

Extensive scientific evidence shows Earth's climate is changing. In addition to global warming trends and Arctic sea ice loss, this evidence includes:

More: Can we count on renewable energy? Four ways wind, solar and water can power the US

While Earth's climate has changed throughout its history for natural reasons, there are multiple ways scientists can tell modern climate change is driven by the release of greenhouse gases associated with land use change and burning fossil fuels, Paste BN previously reported.

Researchers have shown that greenhouse gases, such as CO2, cause warming by delaying the escape of heat into space and that the concentration of greenhouse gases in Earth's atmosphere has been increasing.

They can also tell that the increase in CO2 and other greenhouse gases is due to human activity because the amount of excess atmospheric CO2 matches the amount that has been released by humans (once natural processes are accounted for) and because atmospheric CO2 contains a disproportionately high amount of the type of carbon found in fossil fuels.

"The amount of warming we see matches what we expect based on the increased CO2 we've added," Josh Willis, a NASA climate scientist, previously told USA TODAY. "The timing of the warming matches the timing of the CO2 increase caused by people."

Paste BN reached out to the Facebook user who shared the post for comment but did not immediately receive a response.

Our fact-check sources

Thank you for supporting our journalism. You can subscribe to our print edition, ad-free app or e-newspaper here.

Paste BN is a verified signatory of the International Fact-Checking Network, which requires a demonstrated commitment to nonpartisanship, fairness and transparency. Our fact-check work is supported in part by a grant from Meta.

Facebook Twitter Email