A FoxNews.com article questioned whether 2012 was actually the hottest year on record, quoting “skeptics” who suggest a government office is manipulating data to fabricate proof of rising temperatures. In fact, statistical adjustments made by the agency are required, publicly-documented changes to correct for errors and known sources of bias in the raw data. 

In January, the National Climatic Data Center (NCDC) announced that 2012 was the hottest year on record in the contiguous U.S. - an announcement that Fox News ignored until one of Fox News' few liberal commentators, Bob Beckel, tried to bring it up on The Five. Soon after, FoxNews.com reporter Maxim Lott solicited the views of a few professional climate “skeptics” to claim that scientists made unjustified data adjustments to exaggerate 2012's heat. 

Under the headline “Hottest year ever? Skeptics question revisions to climate data,” Lott quoted Roy Spencer, a rare climate contrarian scientist who considers it his job to “minimize the role of government,” and Steve Goddard, a climate denier-cum-birther writing under a pseudonym, to cast doubt on the temperature record. According to Goddard, the U.S. only “appears” to have warmed as a result of the agency's adjustments, making the data “meaningless garbage.” Lott gave the final word to former television weatherman and blogger Anthony Watts, who said, “In the business and trading world, people go to jail for such manipulations of data.” 

But the NCDC has publicly explained that it needs to make adjustments to the raw temperature data to account for flaws that can result, for example, when stations are moved, are measuring temperatures at different times of day, or are measuring temperature with different instruments. The NCDC carefully applies these adjustments after publishing their methods in multiple peer-reviewed papers. As several scientists tried to explain to FoxNews.com, these adjustments make the temperature data more accurate: 

Government climate scientist Peter Thorne, speaking in his personal capacity, said that there was consensus for the adjustments.

“These have been shown through at least three papers that have appeared in the past 12 months to be an improvement,” he said.

NOAA spokesman Scott Smullen agreed.

“These kinds of improvements get us even closer to the true climate signal, and help our nation even more accurately understand its climate history,” he said.

Peter Thorne, a climate scientist at the Cooperative Institute for Climate and Satellites who was quoted by FoxNews.com, wrote in an email to Media Matters that recent changes to the data served to improve accuracy. The changes were posted prominently by NCDC in the September 2012 State of the Climate report and, according to Thorne, were “supported by extensive documentation” and “flagged with significant due process undertaken prior to release.” 

John Abraham, an IPCC reviewer concluded that Fox News had “misinformed its readers about climate change again.”

UPDATE (1/14/13): Skeptical Science notes that Spencer's own satellite data lists 2012 as the hottest year on record for the contiguous U.S., and states that “If climate contrarians dispute the validity of any of the adjustments made by NCDC, they should subject their criticisms to the scientific peer-review process rather than making unsubstantiated and unjustified accusations of malfeasance in the mainstream media.”