Are Scientists ‘Covering Up’ Global Warming Data?


Government agencies are altering their data to falsify results showing that the planet's climate is getting warmer.


Not True
Like this fact check?


Among the conspiracy theories bandied about by “nature”-themed blogs is the idea that scientists have conspired to gin up mass panics over the planet’s climate-warming emergency.

One particularly hysterical claim was published by NaturalNews in June 2014, as the site “reported” — citing a separate far-right blog — that the National Oceanic and Atmospheric Administration (NOAA) and the National Aeronautics and Space Administration (NASA) had “been caught red-handed altering historical temperature data.”

The claim hinges on readers believing that climate scientists adjusting their findings is done with nefarious intent. A look at the blog’s list of “most viewed articles,” though, shows their reliance on that type of article, among other posts pushing far-right, anti-vaccination, and climate change denial talking points:

The site was not alone in pushing disinformation about a government climate “conspiracy”; as Forbes reported at the time, libertarian group the Heartland Institute published its own report claiming that data from the United States Climate Reference Network (USCRN) showed that “global warming is not so dramatic and uniform as alarmists have claimed.”

According to Forbes, the data in fact validated findings reported by the USCRN’s predecessor, the United States Historical Climatology Network (USHCN):

There are many ups and downs over shorter periods of time, but the full trend is one of rising temperatures. It could be that the further you go back, there could be more variation there might be between the USHCN and USCRN measurements of variance from normal. Perhaps there are other problems in measurement. But in neither case does the information allow intellectually honest and correct declaration that concerns over climate change to be overstated.

In a testament to the staying power of climate-related disinformation, Deke Arndt — who leads NOAA’s climate monitoring efforts — told the fact-checking site LeadStories more about their data-gathering process in October 2019, five years after the initial report from Natural News:

Data are adjusted to correct for non-climate biases like station siting, instrumentation, and so on. The largest factor, on average, are changes in the time of observation: the US was a nation of evening observers in the first part of the 20th century but is now a nation of morning observers. This adjustment is necessary because morning observers can “double count” low temperatures (a very cold morning can be the lowest temperature for the preceding and subsequent day), and evening observers can “double count” very hot afternoons (a very hot afternoon can be the highest temperature for the preceding and subsequent day).

Politicians have also been known to engage in the same kind of anti-science rhetoric. As The Guardian noted in 2016, congressman Lamar Smith (R-Texas) accused NOAA of trying to engineer “politically correct results in an attempt to disprove the eighteen year lack of global temperature increases.”

Smith’s allegations followed a study that year further charting the adjustment between the USCRN and USHCN systems. That report’s lead author, Zeke Hausfather, confirmed that their findings in fact did not show any slowing down on the planet’s overall warming trend.

“Our new study as well as a great deal of prior research shows that adjustments to temperature stations are effective at removing biases introduced by station moves, instrument changes, and other factors,” he said. “The fact that adjustments make the old historical network more similar to the new Climate Reference Network strongly suggests that they are getting it right.”

In November 2022, after a steady drumbeat of disinformation campaigns denying the reality of anthropogenic climate change, a report detailed how effective weaponized narratives have been at derailing policy and affecting individual attitudes on the topic:

[The November 15 2022] report, released by the Climate Action Against Disinformation and Conscious Advertising Network, was based on a YouGov survey conducted across six countries: the US, the UK, India, Brazil. Australia and Germany. It examined public perception of a number of disproven climate myths, as well as denialism.

In the US, 46% of survey respondents said they thought climate change was not caused by human activity, and 23% said that they believed climate change is a hoax made up by the World Economic Forum. Roughly a quarter of Americans surveyed believe that the country can’t afford to reach net-zero emissions by 2050 and that the world in fact doesn’t need to decarbonize and achieve net zero at all to ensure the future welfare and prosperity of humans.

The 2022 report also offered vivid examples of how the narratives work in practice:

In the United States, the two most common net zero misinformation narratives were that the US cannot afford to reach the target of net zero emissions by 2050 and that the world does not need to rapidly de- carbonize and achieve net-zero by 2050 to ensure the prosperity and welfare of humans across the world. Approximately one in four Americans (26%) believes each of these narratives. By contrast, the least believed misinformation narrative in the US was that net-zero policies are a globalist conspiracy to destabilize the US, with one in five (19%) believing this to be true.


In the United States, misinformation belief was consistently highest among regular Fox News consumers.

The effectiveness of long-running, heavily funded disinformation campaigns intended to twist or obscure the reality of a dramatically changing global climate can be readily mitigated by funding and empowering independent journalism and other democratic institutions, and by passing (and acting upon) pro-climate policies; to do otherwise will continue to escalate major, but preventable risks to global security.

11/21/2002, 5:24 PM: This page has been updated with information about COP27 and the corrosive effects of climate change disinformation.  -bb